This document discusses finite element analysis conducted on a piston skirt to analyze deformation and stress distribution. It provides background on pistons and their features. The analysis used finite element modeling to break the piston skirt into small elements and calculate deformation and stress across the piston skirt under load. The modeling process and considerations for finite element analysis are also outlined.
The document discusses tool wear, tool life, and machinability. It defines tool life as the useful cutting time before tool failure or need for resharpening. Tool wear is measured by flank wear and crater wear, and causes include attrition, diffusion, abrasion, and plastic deformation. Machinability is assessed based on surface finish, tool life, cutting forces, and chip control difficulty. Factors like material properties, cutting conditions, tool geometry, and lubrication affect tool wear and machinability.
Machining by broaching removes material in one stroke using a broach tool with gradually increasing cutting teeth. Broaching is used to make holes, slots, gears, and other precision components. Broaching machines come in horizontal and vertical configurations and can be single-station or multi-station. Broaching provides high productivity and precision compared to other machining methods for suitable applications.
Factors affecting tool life in machining processesmohdalaamri
This document discusses factors that affect tool life in machining processes. It identifies the main factors as cutting tool geometry, material, characteristics, cutting conditions, workpiece material, and cutting fluid. Cutting tool geometry influences machined surface quality, productivity, chip control, and forces/temperatures. Cutting tool material and coatings must have properties like heat/wear resistance. Cutting conditions like depth of cut, feed rate, and cutting speed also impact tool life. Workpiece material properties and machinability affect tool performance. Cutting fluids provide lubrication, cooling and chip removal to extend tool life. Environmental impacts of fluids are also considered.
Friction-stir welding is an advanced solid-state joining process (the metal is not melted) which involves the use of a third body tool to join two facing surfaces. Heat is generated between the tool and material which leads to a very soft region near the FSW tool. It then mechanically intermixes the two pieces of metal at the place of the joint, then the softened metal (due to the elevated temperature) can be joined using mechanical pressure (which is applied by the tool), much like joining clay, or dough. It is primarily used on aluminium, and most often on extruded aluminium (non-heat treatable alloys), and on structures which need superior weld strength without a post weld heat treatment.
It was invented and experimentally proven at The Welding Institute UK in December 1991.
This document discusses various types of jigs and fixtures used in machining. It describes different types of drill jigs like leaf jigs, channel jigs, and indexing jigs. It also discusses drill bushings, chip formation during drilling, and various fixtures used for milling, grinding, boring, and other operations. The purpose of jigs and fixtures is to accurately locate and secure workpieces for machining to improve accuracy, consistency, and productivity while reducing errors and rejects. Considerations for designing jigs and fixtures include the workpiece geometry, machine capabilities, and required tolerances.
CNC machines use computer programs and numeric control to operate machine tools like milling machines and lathes. Key features include automated tool changes and multi-axis movement controlled by motors. CNC programming involves specifying coordinates, feed rates, spindle speeds, and preparatory codes like G-codes for different motions and functions. Programs are debugged to ensure accurate machining based on part designs.
The document discusses various methods for manufacturing gears, including:
- Gear shaping and hobbing are generating processes that use rotating cutters to form gear teeth profiles. Gear shaping can produce external and internal spur gears with high accuracy, while hobbing is used for external spur gears and worm wheels.
- Gear milling uses form cutters but requires indexing after each tooth, resulting in lower productivity and accuracy than generating processes.
- Other methods discussed include broaching, rolling, powder metallurgy, casting, and machining smaller gears using EDM or broaching. Finishing processes like grinding, lapping, and burnishing are used to improve gear properties.
The document discusses tool wear, tool life, and machinability. It defines tool life as the useful cutting time before tool failure or need for resharpening. Tool wear is measured by flank wear and crater wear, and causes include attrition, diffusion, abrasion, and plastic deformation. Machinability is assessed based on surface finish, tool life, cutting forces, and chip control difficulty. Factors like material properties, cutting conditions, tool geometry, and lubrication affect tool wear and machinability.
Machining by broaching removes material in one stroke using a broach tool with gradually increasing cutting teeth. Broaching is used to make holes, slots, gears, and other precision components. Broaching machines come in horizontal and vertical configurations and can be single-station or multi-station. Broaching provides high productivity and precision compared to other machining methods for suitable applications.
Factors affecting tool life in machining processesmohdalaamri
This document discusses factors that affect tool life in machining processes. It identifies the main factors as cutting tool geometry, material, characteristics, cutting conditions, workpiece material, and cutting fluid. Cutting tool geometry influences machined surface quality, productivity, chip control, and forces/temperatures. Cutting tool material and coatings must have properties like heat/wear resistance. Cutting conditions like depth of cut, feed rate, and cutting speed also impact tool life. Workpiece material properties and machinability affect tool performance. Cutting fluids provide lubrication, cooling and chip removal to extend tool life. Environmental impacts of fluids are also considered.
Friction-stir welding is an advanced solid-state joining process (the metal is not melted) which involves the use of a third body tool to join two facing surfaces. Heat is generated between the tool and material which leads to a very soft region near the FSW tool. It then mechanically intermixes the two pieces of metal at the place of the joint, then the softened metal (due to the elevated temperature) can be joined using mechanical pressure (which is applied by the tool), much like joining clay, or dough. It is primarily used on aluminium, and most often on extruded aluminium (non-heat treatable alloys), and on structures which need superior weld strength without a post weld heat treatment.
It was invented and experimentally proven at The Welding Institute UK in December 1991.
This document discusses various types of jigs and fixtures used in machining. It describes different types of drill jigs like leaf jigs, channel jigs, and indexing jigs. It also discusses drill bushings, chip formation during drilling, and various fixtures used for milling, grinding, boring, and other operations. The purpose of jigs and fixtures is to accurately locate and secure workpieces for machining to improve accuracy, consistency, and productivity while reducing errors and rejects. Considerations for designing jigs and fixtures include the workpiece geometry, machine capabilities, and required tolerances.
CNC machines use computer programs and numeric control to operate machine tools like milling machines and lathes. Key features include automated tool changes and multi-axis movement controlled by motors. CNC programming involves specifying coordinates, feed rates, spindle speeds, and preparatory codes like G-codes for different motions and functions. Programs are debugged to ensure accurate machining based on part designs.
The document discusses various methods for manufacturing gears, including:
- Gear shaping and hobbing are generating processes that use rotating cutters to form gear teeth profiles. Gear shaping can produce external and internal spur gears with high accuracy, while hobbing is used for external spur gears and worm wheels.
- Gear milling uses form cutters but requires indexing after each tooth, resulting in lower productivity and accuracy than generating processes.
- Other methods discussed include broaching, rolling, powder metallurgy, casting, and machining smaller gears using EDM or broaching. Finishing processes like grinding, lapping, and burnishing are used to improve gear properties.
ELEMENTOS DE MAQUINAS ELEMENTOS ELÁSTICOS, MOLASordenaelbass
O documento discute os elementos elásticos conhecidos como molas, descrevendo suas principais aplicações como armazenamento de energia, amortecimento de choques e distribuição de cargas. Também apresenta os tipos básicos de molas como helicoidais de compressão, tração e torção, além de molas planas, e fornece detalhes sobre suas características dimensionais e aplicações.
Metal spinning is a sheet metal forming process that uses rollers to form axisymmetric parts over a rotating mandrel. There are three main types: conventional spinning, shear spinning, and tube spinning. Spinning can be done hot or cold and involves placing a metal blank against a mandrel and using tools to deform the material into shape as it rotates. Applications include automotive parts, containers, and more. Key advantages are low tooling costs, design flexibility, and little material waste.
The document discusses different types of springs including their materials, applications, advantages, and designs. It provides details on helical, leaf, volute, beam, and Belleville springs. Formulas are given for calculating stresses in helical compression springs based on wire diameter, spring diameter, shear modulus, and applied force. Key aspects of helical spring design like space requirements, forces, tolerances, and environmental conditions are also outlined.
The document discusses abrasive water jet machining (AWJM). It was developed in 1974 to clean metal prior to surface treatment. AWJM involves pumping water at high pressures of 200-400 MPa and passing it through a small orifice to create a high-velocity water jet. Abrasive particles are added to the water jet in the mixing chamber, becoming entrained and accelerating to cut materials 10 times faster than conventional machining of composites. Common abrasives used include silicon carbides and sand.
The one of the major part of CNC Machine is Cutting tools or Inserts. We need to study the Cutting tools and its nomenclature throughly and also study the materials of Cutting tools and types of tools. The Cutting tools are used to remove unwanted materials in the workpiece and to provide a good finish for a customers need.So the Cutting tools is very important to CNC Machine, if there is no cutting tool in CNC Machine, there is no CNC Machine. So the cutting tools are very important to all CNC Machines
This document discusses cutting tools used in machining processes. It defines a cutting tool as any tool that removes metal by shear deformation. Cutting tools must be harder than the material cut and withstand heat. There are two main types: single point and multi-point tools. Single point tools have one cutting edge while multi-point tools have more than two edges, such as milling cutters and drills. Cutting tool materials include high-speed steel, carbides, ceramics, and diamonds. The geometry of single point tools is defined by angles such as back rake, side rake, end relief, and side relief angles, as well as nose radius.
1. O documento discute técnicas de ajustagem mecânica, incluindo o uso de limas e suas propriedades. É descrito como classificar e usar corretamente diferentes tipos de limas para ajustar com precisão peças metálicas de ferro, aço e outros materiais.
2. Detalha as propriedades do aço carbono e ferro fundido, os materiais mais comuns usados em ajustagem. Inclui informações sobre como escolher o tipo correto de material baseado no teor de carbono e aplicação.
3. Fornece in
Riser Design Methods
This document discusses different methods for designing risers for castings, including Caine's method, the modulus method, and the shape factor method. Caine's method uses freezing ratios to determine appropriate riser sizes based on surface area to volume ratios of the casting and riser. The modulus method compares the moduli of the casting and riser. The shape factor method uses a casting's shape factor and desired freezing ratio to determine the required riser volume. Sample problems demonstrate applying each method to calculate riser dimensions and volumes.
1. The document discusses stress concentration which occurs due to sudden changes in geometry like fillets, holes, notches etc. having smaller radii. It increases the actual stress beyond theoretical stress.
2. It also discusses fatigue failure which occurs in materials when subjected to fluctuating loads even if the stresses are below yield strength. Fatigue life of materials is represented using S-N diagrams with endurance limit as the fatigue strength for infinite life.
3. Methods to analyze combined steady and fluctuating stresses like Goodman, Soderberg and Gerber methods are presented. These allow evaluating equivalent stress when the component experiences mean and fluctuating stresses simultaneously.
1) Chip formation involves the shear deformation of work material to form a chip as new material is exposed during cutting.
2) There are four basic types of chips in machining: continuous, discontinuous, serrated, and those with built-up edge (BUE).
3) The type of chip formed depends on factors like the work material, tool geometry, cutting speeds and feeds, and machining environment. Understanding chip formation helps optimize the machining process.
The document discusses friction and heat generation during machining processes. It states that friction between the chip and tool face generates heat, which controls tool wear rate, cutting speed, and material removal rate. There are three zones of heat formation: the shear zone, tool-chip interface, and tool-work interface. It also discusses tool life models, properties required for cutting tool materials, common coating materials used, and factors that influence the selection of cutting parameters and tools for different materials.
This document discusses metal stamping processes and press working equipment. It describes various cutting and forming operations used in stamping like blanking, punching, and bending. Advantages of stamping include small weight, high productivity, accuracy and low cost. Press tools require components for working, structuring, guiding, feeding, locating and stripping the metal piece. Hydraulic presses use oil pressure to actuate the ram while mechanical presses use a crankshaft. Press tools are designed based on the required operation and method of working like simple, compound or progressive dies. Clearance is required between the punch and die to allow for material flow.
The document discusses different types of shaft couplings used to connect shafts. It describes sleeve couplings, split-muff couplings, and flange couplings. For each type, it provides typical design proportions and equations for calculating torque transmission based on factors like shaft diameter, sleeve dimensions, bolt diameter, and allowable stresses. Key aspects like length of coupling components and induced stresses in the sleeve, key, bolts, and flanges are considered in the design process. Marine type flange couplings are also mentioned, which have integral forged flanges held by tapered headless bolts.
This document discusses single point cutting tools. It describes the types of tools, tool geometry including angles and designations. It explains the effects that varying the back rake angle, side rake angle, relief angle, cutting edge angle, and nose radius have on machining. Finally, it lists common tool materials and provides brief conclusions and references.
The document discusses the mechanics of metal cutting. It covers topics such as cutting models, turning forces, power and energies, tool terminology, cutting geometry, material removal rate, orthogonal and oblique cutting models, turning and facing forces, velocities, cutting forces, the merchant's circle diagram, stresses, power, specific cutting energy, and violations of orthogonal cutting models. It provides the theoretical framework for understanding metal cutting and machining processes.
This document discusses mechanics of metal cutting. It covers topics like cutting models, forces, energies, and material removal rate. The orthogonal cutting model is described, which assumes a straight cutting edge generating a plane surface. Key terms like rake angle, shear angle, and cutting forces are defined. The relationships between cutting parameters, forces, power, and specific cutting energy are explained using the orthogonal model. Limitations of this simplified model are also noted.
Tool Wear and Tool life of single point cutting toolAkshay Arvind
Tool wear occurs gradually as material is removed from cutting tools during operation. The three main types of tool wear are flank wear, crater wear, and nose wear. Flank wear increases cutting forces and can cause tool failure if it exceeds 0.5-0.6mm. Crater wear increases the rake angle but weakens the tool. Nose wear shortens the tool and reduces machining accuracy. Factors like cutting speed, depth of cut, tool material, and work material affect the tool's life, which is the length of satisfactory operation before needing replacement due to wear.
The document discusses the analysis of pistons and connecting rods made from different materials when subjected to static and thermal analysis. It analyzes four piston materials - steel, grey cast iron, aluminum alloy, and copper alloy - to determine which has the best strength to weight ratio and lowest stress values. It also models a connecting rod made from an aluminum composite reinforced with silicon carbide and fly ash, finding it has less weight and better stiffness than the standard material. The main objectives are to investigate piston thermal stress distribution under real combustion conditions and determine the total temperature and heat flux on the body.
ELEMENTOS DE MAQUINAS ELEMENTOS ELÁSTICOS, MOLASordenaelbass
O documento discute os elementos elásticos conhecidos como molas, descrevendo suas principais aplicações como armazenamento de energia, amortecimento de choques e distribuição de cargas. Também apresenta os tipos básicos de molas como helicoidais de compressão, tração e torção, além de molas planas, e fornece detalhes sobre suas características dimensionais e aplicações.
Metal spinning is a sheet metal forming process that uses rollers to form axisymmetric parts over a rotating mandrel. There are three main types: conventional spinning, shear spinning, and tube spinning. Spinning can be done hot or cold and involves placing a metal blank against a mandrel and using tools to deform the material into shape as it rotates. Applications include automotive parts, containers, and more. Key advantages are low tooling costs, design flexibility, and little material waste.
The document discusses different types of springs including their materials, applications, advantages, and designs. It provides details on helical, leaf, volute, beam, and Belleville springs. Formulas are given for calculating stresses in helical compression springs based on wire diameter, spring diameter, shear modulus, and applied force. Key aspects of helical spring design like space requirements, forces, tolerances, and environmental conditions are also outlined.
The document discusses abrasive water jet machining (AWJM). It was developed in 1974 to clean metal prior to surface treatment. AWJM involves pumping water at high pressures of 200-400 MPa and passing it through a small orifice to create a high-velocity water jet. Abrasive particles are added to the water jet in the mixing chamber, becoming entrained and accelerating to cut materials 10 times faster than conventional machining of composites. Common abrasives used include silicon carbides and sand.
The one of the major part of CNC Machine is Cutting tools or Inserts. We need to study the Cutting tools and its nomenclature throughly and also study the materials of Cutting tools and types of tools. The Cutting tools are used to remove unwanted materials in the workpiece and to provide a good finish for a customers need.So the Cutting tools is very important to CNC Machine, if there is no cutting tool in CNC Machine, there is no CNC Machine. So the cutting tools are very important to all CNC Machines
This document discusses cutting tools used in machining processes. It defines a cutting tool as any tool that removes metal by shear deformation. Cutting tools must be harder than the material cut and withstand heat. There are two main types: single point and multi-point tools. Single point tools have one cutting edge while multi-point tools have more than two edges, such as milling cutters and drills. Cutting tool materials include high-speed steel, carbides, ceramics, and diamonds. The geometry of single point tools is defined by angles such as back rake, side rake, end relief, and side relief angles, as well as nose radius.
1. O documento discute técnicas de ajustagem mecânica, incluindo o uso de limas e suas propriedades. É descrito como classificar e usar corretamente diferentes tipos de limas para ajustar com precisão peças metálicas de ferro, aço e outros materiais.
2. Detalha as propriedades do aço carbono e ferro fundido, os materiais mais comuns usados em ajustagem. Inclui informações sobre como escolher o tipo correto de material baseado no teor de carbono e aplicação.
3. Fornece in
Riser Design Methods
This document discusses different methods for designing risers for castings, including Caine's method, the modulus method, and the shape factor method. Caine's method uses freezing ratios to determine appropriate riser sizes based on surface area to volume ratios of the casting and riser. The modulus method compares the moduli of the casting and riser. The shape factor method uses a casting's shape factor and desired freezing ratio to determine the required riser volume. Sample problems demonstrate applying each method to calculate riser dimensions and volumes.
1. The document discusses stress concentration which occurs due to sudden changes in geometry like fillets, holes, notches etc. having smaller radii. It increases the actual stress beyond theoretical stress.
2. It also discusses fatigue failure which occurs in materials when subjected to fluctuating loads even if the stresses are below yield strength. Fatigue life of materials is represented using S-N diagrams with endurance limit as the fatigue strength for infinite life.
3. Methods to analyze combined steady and fluctuating stresses like Goodman, Soderberg and Gerber methods are presented. These allow evaluating equivalent stress when the component experiences mean and fluctuating stresses simultaneously.
1) Chip formation involves the shear deformation of work material to form a chip as new material is exposed during cutting.
2) There are four basic types of chips in machining: continuous, discontinuous, serrated, and those with built-up edge (BUE).
3) The type of chip formed depends on factors like the work material, tool geometry, cutting speeds and feeds, and machining environment. Understanding chip formation helps optimize the machining process.
The document discusses friction and heat generation during machining processes. It states that friction between the chip and tool face generates heat, which controls tool wear rate, cutting speed, and material removal rate. There are three zones of heat formation: the shear zone, tool-chip interface, and tool-work interface. It also discusses tool life models, properties required for cutting tool materials, common coating materials used, and factors that influence the selection of cutting parameters and tools for different materials.
This document discusses metal stamping processes and press working equipment. It describes various cutting and forming operations used in stamping like blanking, punching, and bending. Advantages of stamping include small weight, high productivity, accuracy and low cost. Press tools require components for working, structuring, guiding, feeding, locating and stripping the metal piece. Hydraulic presses use oil pressure to actuate the ram while mechanical presses use a crankshaft. Press tools are designed based on the required operation and method of working like simple, compound or progressive dies. Clearance is required between the punch and die to allow for material flow.
The document discusses different types of shaft couplings used to connect shafts. It describes sleeve couplings, split-muff couplings, and flange couplings. For each type, it provides typical design proportions and equations for calculating torque transmission based on factors like shaft diameter, sleeve dimensions, bolt diameter, and allowable stresses. Key aspects like length of coupling components and induced stresses in the sleeve, key, bolts, and flanges are considered in the design process. Marine type flange couplings are also mentioned, which have integral forged flanges held by tapered headless bolts.
This document discusses single point cutting tools. It describes the types of tools, tool geometry including angles and designations. It explains the effects that varying the back rake angle, side rake angle, relief angle, cutting edge angle, and nose radius have on machining. Finally, it lists common tool materials and provides brief conclusions and references.
The document discusses the mechanics of metal cutting. It covers topics such as cutting models, turning forces, power and energies, tool terminology, cutting geometry, material removal rate, orthogonal and oblique cutting models, turning and facing forces, velocities, cutting forces, the merchant's circle diagram, stresses, power, specific cutting energy, and violations of orthogonal cutting models. It provides the theoretical framework for understanding metal cutting and machining processes.
This document discusses mechanics of metal cutting. It covers topics like cutting models, forces, energies, and material removal rate. The orthogonal cutting model is described, which assumes a straight cutting edge generating a plane surface. Key terms like rake angle, shear angle, and cutting forces are defined. The relationships between cutting parameters, forces, power, and specific cutting energy are explained using the orthogonal model. Limitations of this simplified model are also noted.
Tool Wear and Tool life of single point cutting toolAkshay Arvind
Tool wear occurs gradually as material is removed from cutting tools during operation. The three main types of tool wear are flank wear, crater wear, and nose wear. Flank wear increases cutting forces and can cause tool failure if it exceeds 0.5-0.6mm. Crater wear increases the rake angle but weakens the tool. Nose wear shortens the tool and reduces machining accuracy. Factors like cutting speed, depth of cut, tool material, and work material affect the tool's life, which is the length of satisfactory operation before needing replacement due to wear.
The document discusses the analysis of pistons and connecting rods made from different materials when subjected to static and thermal analysis. It analyzes four piston materials - steel, grey cast iron, aluminum alloy, and copper alloy - to determine which has the best strength to weight ratio and lowest stress values. It also models a connecting rod made from an aluminum composite reinforced with silicon carbide and fly ash, finding it has less weight and better stiffness than the standard material. The main objectives are to investigate piston thermal stress distribution under real combustion conditions and determine the total temperature and heat flux on the body.
The document discusses internal combustion engines. It defines an internal combustion engine as one where combustion of fuel occurs within the engine cylinder. It then provides details on the key components of an internal combustion engine, including the cylinder, piston, connecting rod, crankshaft, flywheel, camshaft, intake and exhaust manifolds. Internal combustion engines are classified as either four-stroke or two-stroke depending on the number of revolutions of the crankshaft needed to complete one cycle.
The document discusses internal combustion engines. It provides classifications of IC engines based on fuel type, ignition method, number of strokes, cooling system, and other factors. It then describes the key components of IC engines like the cylinder, piston, connecting rod, crankshaft, and their functions. The document explains the four stroke cycle of IC engines including the intake, compression, power, and exhaust strokes. It also provides diagrams to illustrate engine parts and the four stroke cycle.
1. The document analyzes and compares the thermo-mechanical and vibration properties of an internal combustion engine piston made from three different materials (structural steel, cast iron, and aluminum alloy A2618) under static loading conditions using finite element analysis software ANSYS.
2. Von Mises stresses, strains, heat flux, and natural frequencies are calculated and compared for pistons made of each material. The structural steel piston experiences the highest von Mises stresses and strains while the aluminum alloy piston experiences the lowest values.
3. Material properties such as Young's modulus, Poisson's ratio, density, coefficient of thermal expansion, and shear modulus are provided for each material to be used as inputs for the finite
The document discusses internal combustion engines. It defines an internal combustion engine as a device that releases chemical energy from fuel inside the engine to perform mechanical work. It then classifies engines based on their design, operating cycle, and whether they are 4-stroke or 2-stroke. The document goes on to describe the constructional features of engines, including cylinders, pistons, piston rings, connecting rods, crankshafts, camshafts, valves, bearings, and flywheels. It provides diagrams of diesel and gasoline engine cycles.
This document provides information on piston, rings, and connecting rod components and their purpose and function. It discusses piston and rod construction, inspection procedures, piston ring installation and operation, and connecting rod reconditioning. Key terms related to these components are also defined.
this presentation explains the engine components and 4 stroke cycle engine operations. it also includes other activities that might help the students in understanding the 4 stroke cycle engine operation.
The document discusses the key components of an internal combustion engine and the 4-stroke cycle. It describes the cylinder block, cylinder head, crankshaft, piston and piston rings, connecting rod, bearings, flywheel, and valve train as the main components. It then explains the 4 strokes of the engine cycle: the intake stroke where air/fuel mixture enters; compression stroke where the mixture is compressed; power stroke where combustion provides energy; and exhaust stroke where burned gases exit. The 4 strokes occur sequentially in each cylinder, with all cylinders completing a stroke simultaneously so pistons work together like steps on an engine.
Pistons, rings, and connecting rods are essential components that transfer force between the combustion chamber and crankshaft. Pistons seal the combustion chamber and are attached to connecting rods. Pistons are constructed of cast or forged aluminum alloys and operate at high speeds, transferring force twice per crankshaft revolution. Piston rings include compression rings that seal the combustion chamber from the cylinder wall and an oil control ring that separates oil from the combustion gases. Proper piston, ring, and connecting rod assembly and maintenance are critical for engine performance and efficiency.
The document describes the key components of an internal combustion engine. It lists 16 components: the cylinder, cylinder block, cylinder head, cylinder liner/sleeve, piston, piston head, piston skirt, piston rings, piston pin, connecting rod, crankshaft, flywheel, crankcase, camshaft, timing gear, inlet manifold, and exhaust manifold. It provides details on the purpose and basic design of each component.
The document summarizes the key components and functions of a piston, including its cylindrical shape, role in compressing air and transferring pressure to the crankshaft, and use of rings to seal the cylinder. It also describes piston design features like the crown, ring lands, skirt, and bosses.
The document discusses key parts of internal combustion engines including pistons, valves, spark plugs, cam shafts and describes cylinder arrangements like inline-4 and V6. It also covers topics like engine size measured in cubic centimeters, overhead camshafts, and the four stroke combustion cycle. The summary provides an overview of internal combustion engines, their classification based on fuel type, ignition method, cylinder arrangement and other factors. It outlines the basic idea of how combustion drives the piston to convert the motion to a rotating crankshaft.
The document discusses the components and classification of internal combustion engines. It describes key components like the cylinder block, cylinder head, piston, connecting rod, crankshaft, valves, spark plug, injector, manifold, camshaft, and flywheel. It classifies IC engines based on their cycle of operation, thermodynamic cycle, type of fuel used, ignition method, and cooling system. The main components work together to convert fuel energy into mechanical work through the combustion process.
This document describes a thermo-structural analysis of pistons in an internal combustion engine. Four piston designs - flat, dome, cup, and bowl - were modeled in CATIA and analyzed in ANSYS. Thermal analysis determined temperature distributions and structural analysis determined stress and deformation. The flat and dome pistons made of aluminum alloy AL4032 performed best with lowest stresses of 80.11 MPa and 80.24 MPa respectively and lowest deformations of 0.02 mm and 0.01 mm. Therefore, the flat and dome piston designs provided the most optimal thermal and structural performance.
The document describes the basic parts of an internal combustion engine. It lists 33 main parts, including the cylinder block, cylinder head, piston, connecting rod, crankshaft, camshaft, valves, manifold, flywheel, bearings, and other core components. It provides a brief description of the function of each part and how they interact to convert fuel combustion into rotational motion.
The document describes the main components of an engine. It discusses 16 components including the cylinder, cylinder block, cylinder head, piston, connecting rod, crankshaft, camshaft, flywheel, crankcase, intake manifold, and exhaust manifold. The cylinder provides the combustion space where the piston operates. The connecting rod transmits power from the piston to the crankshaft. The crankshaft converts the reciprocating motion of the piston into rotational motion. The camshaft opens and closes the intake and exhaust valves.
1) Crosshead engines connect the piston to the crankshaft using a crosshead and crosshead pin, allowing for very long strokes. Trunk engines directly connect the piston to the connecting rod.
2) The crosshead design takes side thrust off the piston and liner, allows for better oil distribution, and simplifies piston construction. Trunk pistons have extended skirts to absorb side thrust.
3) Tie bolts are needed to resist the firing forces that try to separate the cylinder block, frames, and bedplate during combustion.
Introduction of piston and piston ringsindogerman77
Cylinder highlights incorporate the cylinder head, cylinder stick bore, cylinder stick, skirt, ring grooves, ring terrains, best locomotive spares, and cylinder rings http://indogermanind.com/
The internal combustion engine has a combustion chamber where fuel is burned. This creates high temperature and pressure gases that are used to do work by expanding. The main components of an internal combustion engine include the cylinder head, cylinder block, pistons, connecting rod, crankshaft, camshaft, valves, flywheel, and systems for fuel, ignition, cooling, lubrication, and filtering air. The engine uses precise timing of its components to intake, compress, combust, and exhaust the fuel-air mixture in order to efficiently convert the chemical energy of the fuel into useful mechanical work.
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
We will explore the capabilities of AI in understanding XML markup languages and autonomously creating structured XML content. Additionally, we will examine the capacity of AI to enrich plain text with appropriate XML markup. Practical examples and methodological guidelines will be provided to elucidate how AI can be effectively prompted to interpret and generate accurate XML markup.
Further emphasis will be placed on the role of AI in developing XSLT, or schemas such as XSD and Schematron. We will address the techniques and strategies adopted to create prompts for generating code, explaining code, or refactoring the code, and the results achieved.
The discussion will extend to how AI can be used to transform XML content. In particular, the focus will be on the use of AI XPath extension functions in XSLT, Schematron, Schematron Quick Fixes, or for XML content refactoring.
The presentation aims to deliver a comprehensive overview of AI usage in XML development, providing attendees with the necessary knowledge to make informed decisions. Whether you’re at the early stages of adopting AI or considering integrating it in advanced XML development, this presentation will cover all levels of expertise.
By highlighting the potential advantages and challenges of integrating AI with XML development tools and languages, the presentation seeks to inspire thoughtful conversation around the future of XML development. We’ll not only delve into the technical aspects of AI-powered XML development but also discuss practical implications and possible future directions.
How to Get CNIC Information System with Paksim Ga.pptxdanishmna97
Pakdata Cf is a groundbreaking system designed to streamline and facilitate access to CNIC information. This innovative platform leverages advanced technology to provide users with efficient and secure access to their CNIC details.
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
Leonard Jayamohan, Partner & Generative AI Lead, Deloitte
This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
Enchancing adoption of Open Source Libraries. A case study on Albumentations.AIVladimir Iglovikov, Ph.D.
Presented by Vladimir Iglovikov:
- https://www.linkedin.com/in/iglovikov/
- https://x.com/viglovikov
- https://www.instagram.com/ternaus/
This presentation delves into the journey of Albumentations.ai, a highly successful open-source library for data augmentation.
Created out of a necessity for superior performance in Kaggle competitions, Albumentations has grown to become a widely used tool among data scientists and machine learning practitioners.
This case study covers various aspects, including:
People: The contributors and community that have supported Albumentations.
Metrics: The success indicators such as downloads, daily active users, GitHub stars, and financial contributions.
Challenges: The hurdles in monetizing open-source projects and measuring user engagement.
Development Practices: Best practices for creating, maintaining, and scaling open-source libraries, including code hygiene, CI/CD, and fast iteration.
Community Building: Strategies for making adoption easy, iterating quickly, and fostering a vibrant, engaged community.
Marketing: Both online and offline marketing tactics, focusing on real, impactful interactions and collaborations.
Mental Health: Maintaining balance and not feeling pressured by user demands.
Key insights include the importance of automation, making the adoption process seamless, and leveraging offline interactions for marketing. The presentation also emphasizes the need for continuous small improvements and building a friendly, inclusive community that contributes to the project's growth.
Vladimir Iglovikov brings his extensive experience as a Kaggle Grandmaster, ex-Staff ML Engineer at Lyft, sharing valuable lessons and practical advice for anyone looking to enhance the adoption of their open-source projects.
Explore more about Albumentations and join the community at:
GitHub: https://github.com/albumentations-team/albumentations
Website: https://albumentations.ai/
LinkedIn: https://www.linkedin.com/company/100504475
Twitter: https://x.com/albumentations
A tale of scale & speed: How the US Navy is enabling software delivery from l...sonjaschweigert1
Rapid and secure feature delivery is a goal across every application team and every branch of the DoD. The Navy’s DevSecOps platform, Party Barge, has achieved:
- Reduction in onboarding time from 5 weeks to 1 day
- Improved developer experience and productivity through actionable findings and reduction of false positives
- Maintenance of superior security standards and inherent policy enforcement with Authorization to Operate (ATO)
Development teams can ship efficiently and ensure applications are cyber ready for Navy Authorizing Officials (AOs). In this webinar, Sigma Defense and Anchore will give attendees a look behind the scenes and demo secure pipeline automation and security artifacts that speed up application ATO and time to production.
We will cover:
- How to remove silos in DevSecOps
- How to build efficient development pipeline roles and component templates
- How to deliver security artifacts that matter for ATO’s (SBOMs, vulnerability reports, and policy evidence)
- How to streamline operations with automated policy checks on container images
“An Outlook of the Ongoing and Future Relationship between Blockchain Technologies and Process-aware Information Systems.” Invited talk at the joint workshop on Blockchain for Information Systems (BC4IS) and Blockchain for Trusted Data Sharing (B4TDS), co-located with with the 36th International Conference on Advanced Information Systems Engineering (CAiSE), 3 June 2024, Limassol, Cyprus.
For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/building-and-scaling-ai-applications-with-the-nx-ai-manager-a-presentation-from-network-optix/
Robin van Emden, Senior Director of Data Science at Network Optix, presents the “Building and Scaling AI Applications with the Nx AI Manager,” tutorial at the May 2024 Embedded Vision Summit.
In this presentation, van Emden covers the basics of scaling edge AI solutions using the Nx tool kit. He emphasizes the process of developing AI models and deploying them globally. He also showcases the conversion of AI models and the creation of effective edge AI pipelines, with a focus on pre-processing, model conversion, selecting the appropriate inference engine for the target hardware and post-processing.
van Emden shows how Nx can simplify the developer’s life and facilitate a rapid transition from concept to production-ready applications.He provides valuable insights into developing scalable and efficient edge AI solutions, with a strong focus on practical implementation.
TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
Sudheer Mechineni, Head of Application Frameworks, Standard Chartered Bank
Discover how Standard Chartered Bank harnessed the power of Neo4j to transform complex data access challenges into a dynamic, scalable graph database solution. This keynote will cover their journey from initial adoption to deploying a fully automated, enterprise-grade causal cluster, highlighting key strategies for modelling organisational changes and ensuring robust disaster recovery. Learn how these innovations have not only enhanced Standard Chartered Bank’s data infrastructure but also positioned them as pioneers in the banking sector’s adoption of graph technology.
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slackshyamraj55
Discover the seamless integration of RPA (Robotic Process Automation), COMPOSER, and APM with AWS IDP enhanced with Slack notifications. Explore how these technologies converge to streamline workflows, optimize performance, and ensure secure access, all while leveraging the power of AWS IDP and real-time communication via Slack notifications.
Unlocking Productivity: Leveraging the Potential of Copilot in Microsoft 365, a presentation by Christoforos Vlachos, Senior Solutions Manager – Modern Workplace, Uni Systems
Removing Uninteresting Bytes in Software FuzzingAftab Hussain
Imagine a world where software fuzzing, the process of mutating bytes in test seeds to uncover hidden and erroneous program behaviors, becomes faster and more effective. A lot depends on the initial seeds, which can significantly dictate the trajectory of a fuzzing campaign, particularly in terms of how long it takes to uncover interesting behaviour in your code. We introduce DIAR, a technique designed to speedup fuzzing campaigns by pinpointing and eliminating those uninteresting bytes in the seeds. Picture this: instead of wasting valuable resources on meaningless mutations in large, bloated seeds, DIAR removes the unnecessary bytes, streamlining the entire process.
In this work, we equipped AFL, a popular fuzzer, with DIAR and examined two critical Linux libraries -- Libxml's xmllint, a tool for parsing xml documents, and Binutil's readelf, an essential debugging and security analysis command-line tool used to display detailed information about ELF (Executable and Linkable Format). Our preliminary results show that AFL+DIAR does not only discover new paths more quickly but also achieves higher coverage overall. This work thus showcases how starting with lean and optimized seeds can lead to faster, more comprehensive fuzzing campaigns -- and DIAR helps you find such seeds.
- These are slides of the talk given at IEEE International Conference on Software Testing Verification and Validation Workshop, ICSTW 2022.
Communications Mining Series - Zero to Hero - Session 1DianaGray10
This session provides introduction to UiPath Communication Mining, importance and platform overview. You will acquire a good understand of the phases in Communication Mining as we go over the platform with you. Topics covered:
• Communication Mining Overview
• Why is it important?
• How can it help today’s business and the benefits
• Phases in Communication Mining
• Demo on Platform overview
• Q/A
Threats to mobile devices are more prevalent and increasing in scope and complexity. Users of mobile devices desire to take full advantage of the features
available on those devices, but many of the features provide convenience and capability but sacrifice security. This best practices guide outlines steps the users can take to better protect personal devices and information.
2. 1. ABSTRACT
For a vehicle engine, the piston is the essential part that bears heavy mechanical and
thermal loads; therefore it has very many influences on the reliability and durability of an
engine. So the piston greatly hinders the increase of power of an engine. Piston dynamics
and friction are two important characteristics determining the performance and the
efficiency of an internal combustion engine. In this project an approach to the behavioral
analysis of the piston skirt is presented that is based mainly on the Finite Element Method
representation. The Finite Element Method was used to predict the deformation of the
piston skirt and also the stress distribution across the piston.
2
3. 2. INTRODUCTION
A piston is a cylindrical engine component that slides back and forth in the cylinder bore
by forces produced during the combustion process. The piston acts as a movable end of
the combustion chamber. The stationary end of the combustion chamber is the cylinder
head. Pistons are commonly made of a cast aluminum alloy for excellent and lightweight
thermal conductivity. Thermal conductivity is the ability of a material to conduct and
transfer heat. Aluminum expands when heated and proper clearance must be provided to
maintain free piston movement in the cylinder bore. Insufficient clearance can cause the
piston to seize in the cylinder. Excessive clearance can cause a loss of compression and
an increase in piston noise. A complete illustration of the piston and its parts are shown
below.
Figure 1 – Piston Features.
Piston features include the piston head, piston pin bore, piston pin, skirt, ring grooves,
ring lands, and piston rings. The piston head is the top surface (closest to the cylinder
3
4. head) of the piston which is subjected to tremendous forces and heat during normal
engine operation.
A piston pin bore is a through hole in the side of the piston perpendicular to piston travel
that receives the piston pin. A piston pin is a hollow shaft that connects the small end of
the connecting rod to the piston. The skirt of a piston is the portion of the piston closest to
the crankshaft that helps align the piston as it moves in the cylinder bore. Some skirts
have profiles cut into them to reduce piston mass and to provide clearance for the rotating
crankshaft counterweights.
A ring groove is a recessed area located around the perimeter of the piston that is used to
retain a piston ring. Ring lands are the two parallel surfaces of the ring groove which
function as the sealing surface for the piston ring. A piston ring is an expandable split
ring used to provide a seal between the piston and the cylinder wall. Piston rings are
commonly made from cast iron. Cast iron retains the integrity of its original shape under
heat, load, and other dynamic forces. Piston rings seal the combustion chamber, conduct
heat from the piston to the cylinder wall, and return oil to the crankcase. Piston ring size
and configuration vary depending on engine design and cylinder material.
Piston rings commonly used on small engines include the compression ring, wiper ring,
and oil ring. A compression ring is the piston ring located in the ring groove closest to the
piston head. The compression ring seals the combustion chamber from any leakage
during the combustion process. When the air-fuel mixture is ignited, pressure from
combustion gases is applied to the piston head, forcing the piston toward the crankshaft.
The pressurized gases travel through the gap between the cylinder wall and the piston and
into the piston ring groove. Combustion gas pressure forces the piston ring against the
cylinder wall to form a seal. Pressure applied to the piston ring is approximately
proportional to the combustion gas pressure.
A wiper ring is the piston ring with a tapered face located in the ring groove between the
compression ring and the oil ring. The wiper ring is used to further seal the combustion
4
5. chamber and to wipe the cylinder wall clean of excess oil. Combustion gases that pass by
the compression ring are stopped by the wiper ring.
An oil ring is the piston ring located in the ring groove closest to the crankcase. The oil
ring is used to wipe excess oil from the cylinder wall during piston movement. Excess oil
is returned through ring openings to the oil reservoir in the engine block. Two-stroke
cycle engines do not require oil rings because lubrication is supplied by mixing oil in the
gasoline, and an oil reservoir is not required.
Pistons are usually made of an aluminum alloy. They are a sliding fit in the cylinders.
This serves several purposes as follows:
Transmits the force of combustion to the crankshaft through the connecting rod.
Acts as a guide for the upper end of the connecting rod.
Serves as a carrier for the piston rings that are used to seal the compression in the
cylinder.
The piston must withstand incredible punishment under temperature extremes. The
following are examples of conditions that a piston must withstand at normal highway
speed:
As the piston moves from the top of the cylinder to the bottom (or vice versa), it
accelerates from a stop to a speed approximately 50 mph at midpoint, and then
decelerates to a stop again. It does this approximately 80 times per second.
The piston is subjected to pressures on its head in excess of 1,000 psi.
The piston head is subjected to temperatures well above 600°F.
Piston is one of the main components composing an engine and a lot of empirical
knowledge and advanced technologies are fully used for the piston design. It has to be
able to handle the abrupt changes in temperature and pressure just above its crown due to
combustion, hence during a cycle it has to handle efficiently the thermal and pressure
loads as well as maintaining the geometry with minimum deformation. The design of a
piston is crucial in determining the efficiency of an engine. Piston quality depends on
optimal geometrical design, body mass and material selection that ensures minimal
5
6. energy loss due to inertia, heat transfer and bore interaction. Structure strength must be
retained against mechanical failure. However, finding the optimal set of the design
parameters is a very challenging job as at every crank angle the piston experiences
different loading. Consequently, the computational tools become very important in piston
design.
Over the years several piston models have been developed. Early piston models were
primarily developed to investigate the piston dynamics and its impact on the cylinder
bore that result in engine vibration and noise, in particular the piston slap phenomenon.
The effects from the lubrication and the piston skirt elasticity in the piston dynamics were
either not considered or assumed insignificant. Nevertheless, valuable information
insights and principles obtained from these studies regarding the piston dynamics have
contributed to the later efforts that attempt to couple lubrication and piston dynamics.
There are essentially two types of piston used in today’s automotive engine and we will
be analyzing about the Mono piston type.
2.1 Mono Piston
By far the most common, and the one used in all passenger car engines, is the mono
piston. As the name suggests, the piston comprises of a single component, which is
usually made from aluminum. The upper part of the piston that supports the combustion
force and holds the piston rings is called the crown. The lower part of the piston that
supports the lateral forces against the inner walls is called the skirt. The piston is linked
to the connecting rod via the wrist pin on which both components are hinged. An
example of a mono piston assembly can be seen in Figure 2 below.
Figure 2 - Schematic drawing of a mono piston assembly.
6
7. 2.2 Articulated Piston
In some heavy duty diesel engines, due to extremely high combustion temperatures and
pressures, it is desirable to have a stainless steel crown section. However, an aluminum
skirt is still preferable due to its low weight and elasticity. Two components of different
materials cannot be rigid joined together in the piston, as their differing coefficients of
expansion would lead to failure. Instead, articulated pistons comprise a stainless steel
crown and an aluminum skirt which are separate components and are hinged separately
on the wrist pin. An example of an articulated piston assembly can be seen in Figure 3
below.
Figure 3 - Schematic drawing of an articulated piston assembly.
The piston motion equations are traditional Newton’s law of vertical and lateral motion
and rotation applied to the piston in standard manner. The forces and moments acting on
a piston are exemplified in Figure 4. These forces and moments come from interactions
of the piston with the liner, rings, wrist pin, connecting rod, cylinder pressure and inertia.
Figure 4 – Forces & Moments acting on the piston.
7
8. 3. Finite Element Analysis
Finite Element Analysis (FEA) is a computer-based numerical technique for calculating
the strength and behavior of engineering structures. It can be used to calculate deflection,
stress, vibration, buckling behavior and many other phenomena. It can be used to analyze
either small or large-scale deflection under loading or applied displacement. It can
analyze elastic deformation, or “permanently bent out of shape” plastic deformation. The
computer is required because of the astronomical number of calculations needed to
analyze a large structure. The power and low cost of modern computers has made Finite
Element Analysis available to many disciplines and companies.
In the Finite Element Method, a structure is broken down into many small simple blocks
or elements. The behavior of an individual element can be described with a relatively
simple set of equations. Just as the set of elements would be joined together to build the
whole structure, the equations describing the behaviors of the individual elements are
joined into an extremely large set of equations that has the behavior of the whole
structure. The computer solves these large sets of simultaneous equations. From the
solution, the computer extracts the behavior of the individual elements. Fro this, it can get
the stress and deflection of all the parts of the structure.
The term “Finite Element” distinguishes the technique from the use of infinitesimal
“differential elements” used in calculus, differential equations and partial differential
equations. The method is also distinguished from finite difference equations, for which
although the steps into which space is divided are finite in size, there is little freedom in
shapes that the discreet steps can be taken. Finite element analysis is a way to deal with
structures that are complex than can be dealt with analytically using partial differential
equations. FEA deals with complex boundaries better than finite differential equations
will, and gives answers to “real world” structural problems.
3.1 How is Finite Element Analysis Useful
Finite Element Analysis makes it possible to evaluate a detailed and complex structure, in
a computer, during the planning of the structure. The demonstration in the computer of
8
9. the adequate strength of the structure and the possibility of improving the design during
planning can justify the cost of this analysis work.
In the absence of Finite Element Analysis, development of structures must be based on
hand calculations only. For complex structures like an automobile, the simplifying
assumptions required to make any calculations possible can lead to a conservative and
heavy design. A considerable factor of ignorance can remain as to whether the structure
will be adequate for all design loads. Significant changes in designs involve risk. With
FEA, the weight of a design can be minimized, and there can be a reduction in the
number of prototypes built.
3.2 Types of Analysis on Structures
Structures can be analyzed for small deflection and elastic material properties (linear
analysis), small deflection and plastic material properties (material non-linearity), large
deflections and elastic material properties (geometric non-linearity) and for simultaneous
large deflection and plastic material properties.
Loads on structures can be represented by using the force of gravity on the mass of the
structure, by applying distributed pressure over surfaces of the structure, or by applying
forces directly to positions in the structure. Displacements of the structure can be
specified at positions in the structure. This can include boundary conditions that imply
symmetric structures where only one portion of the structure is modeled.
3.3 FEA Applications
In theory there is no limit to the number of applications that FEA can be used for. FEA
was born and nurtured in the automotive and aerospace industries but has since spread to
encompass all other sectors of industry, from medical instruments and F1 car design to
plastic molding and watch springs. If it can be designed, then it can be modeled using
FEA.
3.4 Finite Element Analysis Modeling Issues
FEA is approximate: The first issue to understand in finite element analysis is that it is
fundamentally an approximation. The underlying mathematical model may be an
9
10. approximation of the real physical system (for example, the Bernoulli beam ignoring
shear deformation). The finite element itself approximates what happens in its interior
with interpolation formulas. The interior of a 2-D or 3-D finite element has been mapped
to the interior of an element with a perfect shape, so a severely distorted element cannot
deform in a manner that has an accurate match to the real physical response. Integration
over the body of the element is often approximated by Gaussian Quadrature. The
continuity of deformation between connected elements is interrupted at some level. Badly
shaped elements can give less accurate results. A linear analysis is an approximation of
the real behavior. The boundary conditions approximate how the structure is supported
by the outside world. The material properties assumed are approximate. Stress and strain
results are based on the derivatives of the displacement solution, amplifying the errors.
Meshing: Production of good quality mesh is a major issue. The mesh should be fine
enough for good detail where information is needed, but not too fine, or the analysis will
require considerable time and space in the computer. A mesh should have well-shaped
elements – only mild distortion and moderate aspect ratios. This can require considerable
user intervention, despite FEA software promotional claims of automatic good meshing.
Warning about Nodal Coupling: Nodal coupling has its uses: one is a quick and dirty
representation of a bolted or riveted connection with shell elements. More exotic
applications can be invented. When nodal coupling is used to represent a bolted
connection of 3D shells, the nodes that are coupled must occupy the same position in
space. Otherwise, body rotation at that part of the structure will result in artificial
mechanism acting on the structure. High local stresses, and an external couple would
result if the coupled nodes were not located at the same position.
Application of boundary conditions: Structural FEA displacement boundary conditions
are the limitations on movement of the structure at places such as anchor locations. The
boundary conditions in a finite element model must limit translation or rotation in a
manner appropriate to the case at hand. Boundary conditions can be used to imply
symmetric behavior in a structure that has symmetry, so that the model size can be
halved, quartered or similarly reduced, if the loading of the structure is also symmetrical.
Boundary conditions can also be used to imply anti-symmetry, for example, where a
warping displacement is applied to a symmetric structure.
10
11. There are occasions when a displacement boundary condition needs to be applied to a
single node so that the structure can rotate around the support point. This single node
support, however, can result in a serious local stress spike.
Application of loading in a manner that’s of satisfactory accuracy, without becoming
overly complex: It is often sufficient to apply forces directly to a small set of nodes.
However, better representation of loading can be needed to avoid local stress spikes in
some analyses. Application of pressure over a region of elements, producing the desired
force, can help avoid a local stress spike.
Bucking analysis & failure: It can be pursued in two ways: Linear Eigen-value buckling
and geometrically non-linear (large displacement) buckling analysis. Eigen-value
buckling (also known as Euler buckling or classical buckling) will be sufficient for some
structures, but much greater details about stress amplification and margin of safety can be
found with geometrically non-linear analysis. Note that margin of safety is not a simple
concept in a non-linear analysis. The margin of safety will be based on the difference
between the intended design load and either the load that reaches failure conditions or the
load that exceeds allowable set by design codes.
3.5 Failure Modes
1. Static loads lead to stresses exceeding yield over a significant region.
2. Loads on bolts, rivets, spot-welds, plug-welds, stitch-welds, fillet-welds,
bevel-welds, full penetration-welds, adhesives, nails, tie-rods, links or other
connection devices are too high.
3. Strains reach fracture levels in brittle materials.
4. Surface strains cause damage to protective coatings.
5. Buckling of components leads to local damage or progressive collapse.
6. Combined bending and compression leads to excessive stress and failure.
7. Fatigue or sudden fracture is reached.
8. Vibration frequencies are located where applied loading causes damage
through large amplitude response.
11
12. 3.6 Steps in Finite Element Analysis
There are a number of steps in the solution procedure using finite element methods.
1. Specifying Geometry: First the geometry of the structure to be analysed is
defined. This can be done either by entering the geometric information in the
finite element package through the keyboard or mouse, or by importing the model
from a solid modeller like Pro/ENGINEER.
2. Specify Element Type & Material Properties: Next, the material properties are
defined. In an elastic analysis of an isotropic solid these consist of the Young's
modulus and the Poisson's ratio of the material.
3. Mesh the Object: Then, the structure is broken (or meshed) into small elements.
This involves defining the types of elements into which the structure will be
broken, as well as specifying how the structure will be subdivided into elements
(how it will be meshed). This subdivision into elements can either be input by the
user or, with some finite element programs (or add-ons) can be chosen
automatically by the computer based on the geometry of the structure (this is
called auto meshing).
4. Apply Boundary Conditions & External Loads: Next, the boundary conditions
(e.g. location of supports) and the external loads are specified.
5. Generate Solution: Then the solution is generated based on the previously input
parameters.
6. Post – Processing: Based on the initial conditions and applied loads, data is
returned after a solution is processed. This data can be viewed in a variety of
graphs and displays.
7. Refine the Mesh: Finite element methods are approximate methods and, in
general, the accuracy of the approximation increases with the number of elements
used. The number of elements needed for an accurate model depends on the
problem and the specific results to be extracted from it. Thus, in order to judge the
accuracy of results from a single finite element run, you need to increase the
number of elements in the object and see if or how the results change.
8. Interpreting Result: This step is perhaps the most critical step in the entire
analysis because it requires that the modeller use his or her fundamental
12
13. knowledge of mechanics to interpret and understand the output of the model. This
is critical for applying correct results to solve real engineering problems and in
identifying when modelling mistakes have been made (which can easily occur).
The eight steps mentioned above have to be carried out before any meaningful
information can be obtained regardless of the size and complexity of the problem to be
solved.
3.7 FEM Convergence Testing
The convergence testing is started with mesh - discretization, observe and record the
solution. The problem is repeated with a finer mesh (i.e. more elements) and then the
results are compared with the previous test. If the results are nearly similar, then the first
mesh is probably good enough for the particular geometry, loading and constraints. If the
results differ by a large amount however, it will be necessary to try a finer mesh yet.
Finer meshes come with a cost however: more calculation time and large memory
requirements (both disk and RAM)! It is desired to find the minimum number of elements
that gives a converged solution.
13
14. 4. Modeling & Analysis
4.1 Modeling of Piston Assembly
Computer Aided Three Dimensional Application Software (CATIA) was found by
Dassault Systems of France. It was first used by BOEING Engineers and now it is used
widely in aerospace & automobile applications. It has become the global language for all
automobile manufacturers. It is widely used in surface modelling of automobile body. It
is highly user friendly. Its latest version is V5 and the release is R14 and the capabilities
of CATIA are immense.
Modeling in CATIA is comparatively easier than in any other modeling software. CATIA
has various supportive features such as easy profile drawing, extrude, shell, pocket,
revolve, rib. The modeling of the piston assembly is subdivided into following parts:
a) Sketching the profile of the piston and body.
b) Performing operation on the sketch to generate 3-D feature.
c) Additional features.
The piston modeled in Catia is sown below.
Figure 5 – Piston Model.
14
15. 4.2 Steps Involved in FEA of the Piston Assembly
The analysis is done as per standard procedure as follows:
a) Modeling.
b) Material application (Aluminum) as per the specifications.
c) Boundary conditions and loads are loaded as per the real time working
environment.
d) Meshing is done using 10 noded tetrahedron element.
e) Solution phase.
4.3 Material property
The material properties for the piston and piston – pin are as mentioned below:
S. No Property Piston
1. Young’s modulus 68 x 109 Nmm-2
2. Poison ratio 0.35
3. Yield strength 400 x 106 Nmm-2
4. Density 2.7 g/cm3
5. Thermal expansion 24 X 10-6/°C
Table 1 – Material Property.
4.4 Boundary condition
In a numerical simulation, it is impossible and unnecessary to simulate the whole
universe. Generally we choose a region of interest in which we conduct a simulation. The
interesting region has a certain boundary with the surrounding environment. Numerical
simulations also have to consider the physical processes in the boundary region. Different
boundary conditions may cause quiet different simulation results. Improper sets of
boundary conditions may introduce non-physical influences on the simulation system,
while a proper set of boundary conditions can avoid that. The boundary conditions
applied here in the simulation are:
a) Fixed restraints.
b) Pressure force applied on the piston crown.
c) Connecting rod force applied on the piston-boss.
15
16. The pressure force is applied on the top face of the piston crown due to gas force acting
during the combustion. The connecting rod force is calculated as follows:
Piston acceleration, a p = rω 2 (cos θ + λ cos 2θ )
2πn 2 × π × 410
Here θ = 360°, r = 0.05 m, ω = = = 42.94 rad
60 60 s
r 0.05
λ= = = 0.307
l 0.163
a p = 0.05 × (42.94) 2 × (cos 360 + (0.307) cos 720 ) = 120.5 m
s2
Connecting rod force, Fitr = −(m pa + mc −tr )a p
Here mpa = 2.043 kg, mc-tr = 0.735 kg
Fitr = −(2.043 + 0.735) × 120.5 = −335 N
where,
ap = Piston acceleration in m .
s2
θ = Crank angle in Degree.
r = Crank radius in m.
ω = Angular velocity in rad .
s
n = Engine speed in rpm.
l = Length of the connecting rod in m.
λ = Utilization factor, r .
l
Fitr = Connecting rod force in N.
mpa = Mass of piston assembly in kg.
mc-tr = Mass of connecting rod in translational side in kg.
In fixed restraints condition the piston boss outer face and the piston boss inner area are
constrained in 3 translational and 3 rotational directions (ux, uy, uz =0, θx, θy, θz = 0). And
the connecting rod force is applied on the piston boss area. The described boundary
condition is exemplified in the following figures.
16
18. 4.5 Element selection
Once the component is modeled and boundary conditions are applied, the next in analysis
is to discretize the component by using pre-defined elements in the analysis package. The
piston assembly analysis is a three dimensional analysis. Hence a 3D element is used.
Various 3D elements could be used for discretization. The best element should be chosen
to get accurate results and convergence. Solid 95 element type is preferred over the Solid
45 element. Because solid 95 is a higher order version of Solid 45(8 noded element), it
can tolerate irregular shapes without as much loss of accuracy. Solid 95 have compatible
displacement shapes and are well suited to model curved boundaries.
4.6 Comparison of Solid 95 Elements
Criteria Tetrahedral Option Pyramid Option Prism Option
Diagram
No of Nodes 10 13 15
Solving Time Comparatively Less Large Large
Matrix Size RAM
Comparatively Less Large Large
required/
Table 2 –Comparison of Solid 95 Elements.
Based on the comparison details, the best element to achieve accurate meshing, solution
with least solving time and least memory required would be the 10 Noded Tetrahedron.
Also Solid 95 elements have special features to support Plasticity, Creep, Stress
stiffening, Swelling, Deflection, Large Strain, Birth and Death, Adaptive Descent.
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19. 5. Results & Discussion
I. FE Analysis on piston deformation at pressure = 3.8 Mpa & speed = 410 rpm.
Figure 8 –Displacement Contour.
Figure 9 – Displacement Contour.
19
20. Figure 10 – Von Mises Stress Contour.
Figure 11 – Von Mises Stress Contour.
20
21. II. FE Analysis on piston deformation at pressure = 5.5 Mpa & speed = 1060 rpm.
Figure 12 - Displacement Contour.
Figure 13 - Displacement Contour.
21
22. Figure 14 – Von Mises Stress Contour.
Figure 15 - Von Mises Stress Contour.
22
23. III. FE Analysis on piston deformation at pressure = 6 Mpa & speed = 1580 rpm.
Figure 16 - Displacement Contour.
Figure 17 - Displacement Contour.
23
24. Figure 18 – Von Mises Stress Contour.
Figure 19 – Von Mises Stress Contour.
24
25. Maximum
Pressure Speed, Reaction Force, Maximum Von
S. No Displacement,
Mpa RPM N Mises Stress, Nm-2
mm
1 3.8 410 -335 0.0857 4.93 x 107
2 5.5 1060 -2227 0.124 7.13 x 107
3 6 1580 -4943 0.135 7.8 x 107
Table 3 –Displacement & Von Mises Stress at different cases.
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26. 6. Conclusion
The piston has been designed to study the skirt deformation under several operating
conditions using finite element method. Empirical equations are used to calculate the
connecting rod forces and the boundary conditions are developed to simulate the exact
constraints with some simplifications. In the final observation the skirt deformation was
maximum on the thrust side of the piston and the reasons for this are the eccentricity in
the piston pin and the firing chamber.
The piston skirt profile relates to the piston slap phenomena that affect the skirt liner
impact forces, skirt lubrication, friction and liner cavitations. By predicting the secondary
motion of the piston, the power cylinder system can be modified in early design phase.
However, the piston design changes made to improve piston guidance in cylinder and
thereby reduce piston slap noise often have a negative impact on piston friction.
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27. 7. References
Andreas Panayi, Harold Schock, Boon-Keat Chui & Mikhail Ejakov,
“Parameterization and FEA Approach for the Assessment of Piston
Characterstics”, SAE Paper No. 2006-01-0429.
S.H.Mansouri & V.W.Wong, “Effects of Piston Design Parameters on Piston
Secondary Motion and Skirt-Liner Friction”, SAE Paper No. 2004-01-2911.
You Zhang, Yong Zhang, Bin Gao & Baozhong Zhang, “Structure Design & FEA
of LHR Piston for Vehicle Engines”, SAE Paper No. 981488.
Shivakanth N.Kurbet & R. Krishna Kumar, “Mechanics and Stress Analysis of
Piston Ring in Multibody Single Cylinder Internal Combustion Engine – FE
Analysis”, SAE Paper No. 2001-01-3371.
Tetsuya Kimura, Kazuki Takahashi & Shigeru Sugiyama, “Development of a
Piston Secondary Motion Analysis Program with Elastically Deformable Piston
Skirt”, SAE Paper No. 1999-01-3303.
Mikhail A. Ejakov, Analytical Powertrain Department, Ford Motor Company –
Piston/Piston Ring Dynamics CAE.
B.Lawton & D.E.G.Crutcher, “Mechanical Stresses in Pistons, Gudgeon Pins &
Connecting rods”, IMechE 2002.
B.L.Ruddy & F.H.Kinsella, “Computer Aided Engineering for Pistons, Rings &
Pins”, IMech 1990.
Conor P.McNally, “Development of a Numerical Model of Piston Secondary
Motion for Internal Combustion Engines”.
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