CFD is a branch of fluid mechanics that uses
numerical methods and algorithms to solve and analyze
problems that involve fluid flows. Computers are used to
perform the calculations required to simulate the interaction
of liquids and gases with surfaces defined by boundary
conditions. In this thesis, CFD analysis of flow within
Convergent-Divergent supersonic nozzle of different cross
sections rectangular, square and circular has been performed.
The analysis has been performed according to the shape of the
supersonic nozzle and keeping the same input conditions. Our
objective is to investigate the best suited nozzle which gives
high exit velocity among the different cross sections
considered. The application of these nozzles is mainly in
torpedos. The work is carried out in two stages: 1.Modeling
and analysis of flow for supersonic nozzles of different cross
sections.2.Prediction of best suited nozzle among the nozzles
considered. In this, initially modeling of the nozzles has been
done in CATIA and later on mesh generation and analysis
have been carried out in ANSYS FLUENT 14.5 and various
contours like velocity, pressure, temperature have been taken
and their variation according to different nozzles has been
studied.
This document discusses various topics related to heat transfer including the three main modes of heat transfer: conduction, convection, and radiation. It provides the governing equations for each, including Fourier's law of conduction, Newton's law of cooling for convection, and Stefan-Boltzmann law for radiation. Specific topics covered include steady state and transient conduction, extended surfaces, heat exchangers, and free and forced convection. Equations are also derived for one-dimensional conduction under steady state conditions with and without heat generation.
1) A reciprocating compressor takes in air or gas at low pressure and compresses it using pistons moving back and forth in cylinders.
2) It is classified based on design, number of stages, pressure ratio, capacity, number of cylinders, type of fluid, and cooling method.
3) In single stage reciprocating compression, air is drawn into the cylinder on the inward stroke and compressed on the outward stroke through inlet and outlet valves.
Study and analysis of convergent Divergent Nozzle Using CFDAkhilendra Akki
This document presents a study analyzing a convergent-divergent nozzle using computational fluid dynamics (CFD). It discusses modeling a convergent-divergent nozzle geometry in ANSYS Fluent, meshing the model, applying boundary conditions, and obtaining results like pressure, velocity, and temperature contours and plots. The objective is to compare cases with different convergent and divergent angles and area ratios to determine the best suitable nozzle design based on calculated flow parameters.
When a body moves through a fluid, it experiences two forces: drag and lift. Drag acts parallel to the flow and slows the body down, while lift acts perpendicular to the flow. These forces depend on factors like the fluid's velocity and density, the body's size and shape, and its angle of attack relative to the flow. Streamlined shapes with small frontal areas experience less pressure drag than blunt bodies, which experience boundary layer separation and higher pressures on one side. The forces can be calculated using drag and lift coefficients, which vary based on the Reynolds number and other flow properties.
This document summarizes the testing and performance of diesel and petrol engines. It describes the key components and operating principles of diesel and petrol engines. It then discusses various performance characteristics of internal combustion engines that are used to evaluate engine performance, such as brake thermal efficiency, indicated thermal efficiency, specific fuel consumption, mechanical efficiency, volumetric efficiency, air fuel ratio, and mean effective pressure. The performance of engines is tested by measuring fuel consumption, brake power, and specific power output using various types of dynamometers.
This document provides information about axial flow compressors including:
- They consist of multiple rows of fixed and moving blades that continuously pressurize gas flowing parallel to the axis of rotation, achieving high efficiency and mass flow.
- Each pair of rotor and stator blades constitutes a pressure stage, with typical single stage pressure increases of 15-60% and multiple stages used to achieve higher overall pressure ratios.
- Stalling and surging refer to unstable flow conditions that reduce compressor performance and must be avoided through proper design and operation.
- They find applications in industries like oil refining and power generation as well as aircraft engines due to their high performance capabilities.
This document provides information about diesel power plants. It discusses the key components of a diesel power plant including the diesel engine, intake and exhaust systems, fuel supply system, cooling system, lubrication system, and governing system. It notes that diesel power plants can generate power in the range of 2-50 MW and are favored in locations where sufficient coal/water are not available. The advantages of diesel power plants are also summarized, such as their simple design, small footprint, and ability for quick startup.
This document provides short questions and answers related to gas dynamics and jet propulsion for a 6th semester mechanical engineering course. It covers topics like basic concepts of compressible flow, stagnation properties, flow through nozzles and diffusers, and flow through ducts. The questions define key terms, derive important equations, and ask students to analyze example problems involving isentropic flow of air through nozzles and ducts. The document aims to test students' understanding of fundamental compressible flow concepts and their ability to apply equations of compressible flow to practical problems.
This document discusses various topics related to heat transfer including the three main modes of heat transfer: conduction, convection, and radiation. It provides the governing equations for each, including Fourier's law of conduction, Newton's law of cooling for convection, and Stefan-Boltzmann law for radiation. Specific topics covered include steady state and transient conduction, extended surfaces, heat exchangers, and free and forced convection. Equations are also derived for one-dimensional conduction under steady state conditions with and without heat generation.
1) A reciprocating compressor takes in air or gas at low pressure and compresses it using pistons moving back and forth in cylinders.
2) It is classified based on design, number of stages, pressure ratio, capacity, number of cylinders, type of fluid, and cooling method.
3) In single stage reciprocating compression, air is drawn into the cylinder on the inward stroke and compressed on the outward stroke through inlet and outlet valves.
Study and analysis of convergent Divergent Nozzle Using CFDAkhilendra Akki
This document presents a study analyzing a convergent-divergent nozzle using computational fluid dynamics (CFD). It discusses modeling a convergent-divergent nozzle geometry in ANSYS Fluent, meshing the model, applying boundary conditions, and obtaining results like pressure, velocity, and temperature contours and plots. The objective is to compare cases with different convergent and divergent angles and area ratios to determine the best suitable nozzle design based on calculated flow parameters.
When a body moves through a fluid, it experiences two forces: drag and lift. Drag acts parallel to the flow and slows the body down, while lift acts perpendicular to the flow. These forces depend on factors like the fluid's velocity and density, the body's size and shape, and its angle of attack relative to the flow. Streamlined shapes with small frontal areas experience less pressure drag than blunt bodies, which experience boundary layer separation and higher pressures on one side. The forces can be calculated using drag and lift coefficients, which vary based on the Reynolds number and other flow properties.
This document summarizes the testing and performance of diesel and petrol engines. It describes the key components and operating principles of diesel and petrol engines. It then discusses various performance characteristics of internal combustion engines that are used to evaluate engine performance, such as brake thermal efficiency, indicated thermal efficiency, specific fuel consumption, mechanical efficiency, volumetric efficiency, air fuel ratio, and mean effective pressure. The performance of engines is tested by measuring fuel consumption, brake power, and specific power output using various types of dynamometers.
This document provides information about axial flow compressors including:
- They consist of multiple rows of fixed and moving blades that continuously pressurize gas flowing parallel to the axis of rotation, achieving high efficiency and mass flow.
- Each pair of rotor and stator blades constitutes a pressure stage, with typical single stage pressure increases of 15-60% and multiple stages used to achieve higher overall pressure ratios.
- Stalling and surging refer to unstable flow conditions that reduce compressor performance and must be avoided through proper design and operation.
- They find applications in industries like oil refining and power generation as well as aircraft engines due to their high performance capabilities.
This document provides information about diesel power plants. It discusses the key components of a diesel power plant including the diesel engine, intake and exhaust systems, fuel supply system, cooling system, lubrication system, and governing system. It notes that diesel power plants can generate power in the range of 2-50 MW and are favored in locations where sufficient coal/water are not available. The advantages of diesel power plants are also summarized, such as their simple design, small footprint, and ability for quick startup.
This document provides short questions and answers related to gas dynamics and jet propulsion for a 6th semester mechanical engineering course. It covers topics like basic concepts of compressible flow, stagnation properties, flow through nozzles and diffusers, and flow through ducts. The questions define key terms, derive important equations, and ask students to analyze example problems involving isentropic flow of air through nozzles and ducts. The document aims to test students' understanding of fundamental compressible flow concepts and their ability to apply equations of compressible flow to practical problems.
This document discusses different types of steam turbines and their operating principles. It describes impulse turbines where steam expands within nozzles and does not change pressure as it passes over blades. Reaction turbines gradually decrease pressure as steam passes over fixed and moving blades. Compounding methods are also presented, including velocity compounding using multiple blade rings, pressure compounding with nozzle stages, and pressure-velocity compounding combining both methods. The document aims to explain steam turbine design and operation.
This document discusses fluid mechanics concepts relevant to sports, including drag, lift, buoyancy, and the Magnus effect. It explains that fluid mechanics is the study of forces exerted on objects moving through fluids like air and water. These forces can significantly impact sports like swimming, cycling, and tennis. The document defines key fluid forces like drag, which acts opposite the object's motion, and lift, which acts perpendicular to motion. It also provides equations to calculate drag and lift forces and discusses how surface smoothness and cross-sectional area affect drag. The Magnus effect causes sidespin on balls due to rotational forces. The document instructs choosing a topic for a presentation on fluid mechanics in sports.
This lab manual document provides instructions for experiments on heat transfer in a Mechanical Engineering department. The first experiment listed is on heat transfer from a pin-fin apparatus. The objective is to calculate the heat transfer coefficient for natural and forced convection from a fin. The experiment involves measuring temperatures along a brass fin heated at one end while air passes over it naturally or in a duct. The second experiment listed is on heat transfer through a composite wall, and involves determining the total thermal resistance and conductivity of a wall made of different slab materials sandwiching a heater.
The document summarizes three turbulence models: the standard k-ε model, RNG k-ε model, and realizable k-ε model. The major differences between the models are their methods of calculating turbulent viscosity, turbulent Prandtl numbers, and generation/destruction terms. Some features are similar between the models, including turbulent production, buoyancy effects, and modeling heat/mass transfer. The realizable k-ε model addresses deficiencies of previous models like predicting round jet spreading rates. Buoyancy effects are included in all three models through modifications to the turbulent kinetic energy generation term.
The document presents information on a bootstrap air cooling system suitable for aircraft. It consists of two heat exchangers, a secondary compressor driven by a turbine, and uses ram air and compression to cool and circulate air. Ambient air is compressed by the main aircraft compressor then cooled in an air cooler before further compression and cooling. It is then expanded through a turbine to provide cooled air to the aircraft cabin. Advantages are that air is readily available, non-toxic, and pressures are low. A limitation is that it requires aircraft flight for ram air cooling and is not suitable for ground use without an additional fan.
Reaction and Impulse Turbine (Comparison)Aman Singh
This document compares reaction and impulse turbines. It states that impulse turbines use nozzles to direct steam onto curved buckets, extracting kinetic energy from the steam. Reaction turbines have fixed and moving blades with the steam gliding over both and losing pressure. The key differences are that impulse turbines use steam kinetic energy from nozzles while reaction turbines use both pressure and kinetic energy, and that impulse turbine blades are symmetrical while reaction turbine blades are asymmetrical. Most efficient steam turbines use a combination of impulse and reaction stages.
This document summarizes a computational fluid dynamics (CFD) analysis of flow over a NACA 0012 airfoil at attack angles of 2 and 14 degrees. Meshes with 15,000 and 40,000 elements were tested, with lift and drag coefficients increasing with higher mesh resolution and attack angle. Pressure contours, velocity vectors, and other flow visualizations were obtained from the CFD simulations in ANSYS. While mesh independence was achieved at 2 degrees, it was not at 14 degrees, which is above the airfoil's stall angle.
Turbines convert hydraulic energy from flowing water into mechanical energy via a shaft. Francis turbines, invented in 1848, are a common type of inward reaction turbine that convert both kinetic and pressure energy. They have main components like a spiral casing, guide vanes, runner, and draft tube. Pelton wheels are impulse turbines that use nozzles to convert water's pressure energy into kinetic energy before it strikes buckets on the runner to rotate it. They are suitable for high head applications.
Boiler draught refers to the pressure difference between the air inside a boiler furnace and the outside air, which causes the flow of air and flue gases through the boiler. This pressure difference is necessary for proper combustion of fuel and removal of flue gases. Draught can be produced naturally through the use of a chimney, or artificially through mechanical fans or steam jets. Forced draught uses a fan before the furnace to push air and gases through, while induced draught uses a fan at the chimney to pull gases through. Balanced draught combines the two. Mechanical draught allows better control of the pressure but has higher costs than natural or steam jet draught.
The document discusses combustion in diesel engines. It describes the four stages of combustion: ignition delay period, rapid combustion period, controlled combustion period, and after-burning period. It explains factors that affect the ignition delay period such as compression ratio, engine speed, fuel quality, and intake conditions. The document also discusses knock in diesel engines and different combustion chamber designs for diesel engines, including direct injection and indirect injection types.
Need for cooling of an aircraft. types of air-refrigeration system, DART, Advantages of air refrigeration system, Open and closed cycle air refrigeration,
When an aerodynamic body moves through air faster than the speed of sound, shock waves are generated ahead of the body. At subsonic speeds, sound waves propagate outward in circles around the moving body. But at supersonic speeds, the body moves faster than the speed of the sound waves it generates, so the sound waves are always behind the body. As pressure waves accumulate ahead of a supersonic body, they can merge into shock waves. Shock waves instantaneously compress the gas by obtaining kinetic energy from the upstream flow, heating the gas above isentropic compression temperatures and increasing entropy through an irreversible process.
The document discusses different types of compressors used to compress gases. It describes positive displacement compressors like reciprocating, screw, and rotary vane compressors which work by reducing the gas volume. Dynamic compressors like centrifugal compressors are also discussed which increase gas pressure using an impeller. Key components, working principles, advantages and disadvantages of reciprocating, screw, rotary vane and centrifugal compressors are summarized. Selection factors for compressors like required pressure, flow rates, piston speed and system layout are also highlighted.
Prime movers are devices that convert energy into mechanical work. The document discusses two main types of prime movers - steam engines and steam turbines. It provides details on the components, working, and types of steam turbines, including impulse and reaction turbines. The key components of steam turbines are nozzles, blades (fixed and moving), rotors, and shafts. Steam turbines work by converting the pressure energy of steam into kinetic energy and then into rotational mechanical energy to power the turbine shaft.
Energy Conservation in Compressed Air System.AffanDabir
Compressed air systems can be inefficient, wasting up to 70-90% of the energy used to power compressors. Common issues include leaks, over pressurization, pressure drops, and misuse of compressed air for applications where other technologies would be more efficient. Implementing conservation measures like leak detection and repair, pressure optimization, proper sizing of distribution components, and replacing pneumatic tools with electric where possible can significantly reduce energy costs over the long term. Regular maintenance and monitoring compressor run times and pressures can also improve efficiency.
Machine design possible interview questionsDr. Ramesh B
The document discusses ISO quality standards and their applications. ISO-9001 applies to design, development, production and servicing. ISO-9002 is for production and servicing, and ISO-9003 is for final inspection and testing. It also provides definitions and applications of various mechanical engineering terms related to machine elements, materials, design, analysis and computer-aided design.
The document discusses different types of engine cycles including ideal, fuel-air, and actual cycles. It provides details on:
- Air standard cycles which are idealized and assume a perfect gas, no mass change, reversible processes, and constant specific heats. Examples include Otto, Diesel, and Dual cycles.
- Fuel-air cycles which are more accurate by considering the actual cylinder gas composition, variable specific heats, incomplete fuel-air mixing at high temps, and dissociation effects.
- Actual engine cycles use even more accurate models of the processes and working fluid, taking into account variable properties and chemical reactions.
The document discusses various factors that affect the efficiency of internal combustion engines such as specific heat, dissociation, premixed vs non-premixed fuel charges, and different types of losses in actual engine cycles compared to ideal cycles. It notes that the actual efficiency of a good engine is around 25% of the estimated efficiency from the ideal air standard cycle due to losses from factors like heat transfer, combustion, pumping, and blow-by. Fuel-air ratio can impact maximum power output due to chemical equilibrium losses. Variable specific heats can increase maximum pressure but decrease maximum temperature compared to constant specific heats.
The document discusses centrifugal compressors. It begins with an introduction to air compressors in general, then describes the two main types: positive-displacement and dynamic-displacement. It focuses on centrifugal compressors, which use a rotating impeller to impart kinetic energy to air and compress it. The key components of a centrifugal compressor are the inlet, impeller, diffuser, and collector. Centrifugal compressors are commonly used in applications like gas turbines, turbochargers, pipelines, and HVAC due to benefits like fewer parts and higher efficiency compared to reciprocating compressors. However, they have a lower maximum compression ratio than reciprocating compressors.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
This document discusses different types of steam turbines and their operating principles. It describes impulse turbines where steam expands within nozzles and does not change pressure as it passes over blades. Reaction turbines gradually decrease pressure as steam passes over fixed and moving blades. Compounding methods are also presented, including velocity compounding using multiple blade rings, pressure compounding with nozzle stages, and pressure-velocity compounding combining both methods. The document aims to explain steam turbine design and operation.
This document discusses fluid mechanics concepts relevant to sports, including drag, lift, buoyancy, and the Magnus effect. It explains that fluid mechanics is the study of forces exerted on objects moving through fluids like air and water. These forces can significantly impact sports like swimming, cycling, and tennis. The document defines key fluid forces like drag, which acts opposite the object's motion, and lift, which acts perpendicular to motion. It also provides equations to calculate drag and lift forces and discusses how surface smoothness and cross-sectional area affect drag. The Magnus effect causes sidespin on balls due to rotational forces. The document instructs choosing a topic for a presentation on fluid mechanics in sports.
This lab manual document provides instructions for experiments on heat transfer in a Mechanical Engineering department. The first experiment listed is on heat transfer from a pin-fin apparatus. The objective is to calculate the heat transfer coefficient for natural and forced convection from a fin. The experiment involves measuring temperatures along a brass fin heated at one end while air passes over it naturally or in a duct. The second experiment listed is on heat transfer through a composite wall, and involves determining the total thermal resistance and conductivity of a wall made of different slab materials sandwiching a heater.
The document summarizes three turbulence models: the standard k-ε model, RNG k-ε model, and realizable k-ε model. The major differences between the models are their methods of calculating turbulent viscosity, turbulent Prandtl numbers, and generation/destruction terms. Some features are similar between the models, including turbulent production, buoyancy effects, and modeling heat/mass transfer. The realizable k-ε model addresses deficiencies of previous models like predicting round jet spreading rates. Buoyancy effects are included in all three models through modifications to the turbulent kinetic energy generation term.
The document presents information on a bootstrap air cooling system suitable for aircraft. It consists of two heat exchangers, a secondary compressor driven by a turbine, and uses ram air and compression to cool and circulate air. Ambient air is compressed by the main aircraft compressor then cooled in an air cooler before further compression and cooling. It is then expanded through a turbine to provide cooled air to the aircraft cabin. Advantages are that air is readily available, non-toxic, and pressures are low. A limitation is that it requires aircraft flight for ram air cooling and is not suitable for ground use without an additional fan.
Reaction and Impulse Turbine (Comparison)Aman Singh
This document compares reaction and impulse turbines. It states that impulse turbines use nozzles to direct steam onto curved buckets, extracting kinetic energy from the steam. Reaction turbines have fixed and moving blades with the steam gliding over both and losing pressure. The key differences are that impulse turbines use steam kinetic energy from nozzles while reaction turbines use both pressure and kinetic energy, and that impulse turbine blades are symmetrical while reaction turbine blades are asymmetrical. Most efficient steam turbines use a combination of impulse and reaction stages.
This document summarizes a computational fluid dynamics (CFD) analysis of flow over a NACA 0012 airfoil at attack angles of 2 and 14 degrees. Meshes with 15,000 and 40,000 elements were tested, with lift and drag coefficients increasing with higher mesh resolution and attack angle. Pressure contours, velocity vectors, and other flow visualizations were obtained from the CFD simulations in ANSYS. While mesh independence was achieved at 2 degrees, it was not at 14 degrees, which is above the airfoil's stall angle.
Turbines convert hydraulic energy from flowing water into mechanical energy via a shaft. Francis turbines, invented in 1848, are a common type of inward reaction turbine that convert both kinetic and pressure energy. They have main components like a spiral casing, guide vanes, runner, and draft tube. Pelton wheels are impulse turbines that use nozzles to convert water's pressure energy into kinetic energy before it strikes buckets on the runner to rotate it. They are suitable for high head applications.
Boiler draught refers to the pressure difference between the air inside a boiler furnace and the outside air, which causes the flow of air and flue gases through the boiler. This pressure difference is necessary for proper combustion of fuel and removal of flue gases. Draught can be produced naturally through the use of a chimney, or artificially through mechanical fans or steam jets. Forced draught uses a fan before the furnace to push air and gases through, while induced draught uses a fan at the chimney to pull gases through. Balanced draught combines the two. Mechanical draught allows better control of the pressure but has higher costs than natural or steam jet draught.
The document discusses combustion in diesel engines. It describes the four stages of combustion: ignition delay period, rapid combustion period, controlled combustion period, and after-burning period. It explains factors that affect the ignition delay period such as compression ratio, engine speed, fuel quality, and intake conditions. The document also discusses knock in diesel engines and different combustion chamber designs for diesel engines, including direct injection and indirect injection types.
Need for cooling of an aircraft. types of air-refrigeration system, DART, Advantages of air refrigeration system, Open and closed cycle air refrigeration,
When an aerodynamic body moves through air faster than the speed of sound, shock waves are generated ahead of the body. At subsonic speeds, sound waves propagate outward in circles around the moving body. But at supersonic speeds, the body moves faster than the speed of the sound waves it generates, so the sound waves are always behind the body. As pressure waves accumulate ahead of a supersonic body, they can merge into shock waves. Shock waves instantaneously compress the gas by obtaining kinetic energy from the upstream flow, heating the gas above isentropic compression temperatures and increasing entropy through an irreversible process.
The document discusses different types of compressors used to compress gases. It describes positive displacement compressors like reciprocating, screw, and rotary vane compressors which work by reducing the gas volume. Dynamic compressors like centrifugal compressors are also discussed which increase gas pressure using an impeller. Key components, working principles, advantages and disadvantages of reciprocating, screw, rotary vane and centrifugal compressors are summarized. Selection factors for compressors like required pressure, flow rates, piston speed and system layout are also highlighted.
Prime movers are devices that convert energy into mechanical work. The document discusses two main types of prime movers - steam engines and steam turbines. It provides details on the components, working, and types of steam turbines, including impulse and reaction turbines. The key components of steam turbines are nozzles, blades (fixed and moving), rotors, and shafts. Steam turbines work by converting the pressure energy of steam into kinetic energy and then into rotational mechanical energy to power the turbine shaft.
Energy Conservation in Compressed Air System.AffanDabir
Compressed air systems can be inefficient, wasting up to 70-90% of the energy used to power compressors. Common issues include leaks, over pressurization, pressure drops, and misuse of compressed air for applications where other technologies would be more efficient. Implementing conservation measures like leak detection and repair, pressure optimization, proper sizing of distribution components, and replacing pneumatic tools with electric where possible can significantly reduce energy costs over the long term. Regular maintenance and monitoring compressor run times and pressures can also improve efficiency.
Machine design possible interview questionsDr. Ramesh B
The document discusses ISO quality standards and their applications. ISO-9001 applies to design, development, production and servicing. ISO-9002 is for production and servicing, and ISO-9003 is for final inspection and testing. It also provides definitions and applications of various mechanical engineering terms related to machine elements, materials, design, analysis and computer-aided design.
The document discusses different types of engine cycles including ideal, fuel-air, and actual cycles. It provides details on:
- Air standard cycles which are idealized and assume a perfect gas, no mass change, reversible processes, and constant specific heats. Examples include Otto, Diesel, and Dual cycles.
- Fuel-air cycles which are more accurate by considering the actual cylinder gas composition, variable specific heats, incomplete fuel-air mixing at high temps, and dissociation effects.
- Actual engine cycles use even more accurate models of the processes and working fluid, taking into account variable properties and chemical reactions.
The document discusses various factors that affect the efficiency of internal combustion engines such as specific heat, dissociation, premixed vs non-premixed fuel charges, and different types of losses in actual engine cycles compared to ideal cycles. It notes that the actual efficiency of a good engine is around 25% of the estimated efficiency from the ideal air standard cycle due to losses from factors like heat transfer, combustion, pumping, and blow-by. Fuel-air ratio can impact maximum power output due to chemical equilibrium losses. Variable specific heats can increase maximum pressure but decrease maximum temperature compared to constant specific heats.
The document discusses centrifugal compressors. It begins with an introduction to air compressors in general, then describes the two main types: positive-displacement and dynamic-displacement. It focuses on centrifugal compressors, which use a rotating impeller to impart kinetic energy to air and compress it. The key components of a centrifugal compressor are the inlet, impeller, diffuser, and collector. Centrifugal compressors are commonly used in applications like gas turbines, turbochargers, pipelines, and HVAC due to benefits like fewer parts and higher efficiency compared to reciprocating compressors. However, they have a lower maximum compression ratio than reciprocating compressors.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
The document provides details on the operation and design of gas turbine engines. It explains that air is compressed, mixed with fuel and ignited to produce hot gas, which is then used to power a turbine. The turbine provides work to drive the compressor. There are usually multiple compression and turbine stages. Design considerations include cooling turbine blades, increasing efficiency through spooled shafts, and applications in aircraft like reverse thrust and vectored thrust nozzles.
1) A turbocharger uses the engine's exhaust gases to drive a turbine connected to an air compressor, increasing air intake and allowing more fuel to be burned for higher engine power.
2) Types of superchargers include centrifugal, roots, and vane compressors, while turbochargers consist of a turbine and compressor on a shared shaft.
3) Advantages of superchargers and turbochargers include increased engine power, especially at high altitudes, while disadvantages include added cost, complexity, and risks of detonation.
Update On June One Presenting at the Power & Energy Conference, Power Energy 2017-3191 “New Tech Combined Cycle Gas Turbines (CCGT) - Analysis of Water Swirled into Gas Turbine Technology” - Thursday, June 29th in the session that is scheduled from 2:00 – 3:30 pm”. Recently I did TG Advisors May 2017 two day course on gas turbine / steam turbine electrical generation. There were enough changes that I am sharing a paper about my technology. This presentation is to preliminarily explain and analyze a system inclusive of the benefits of water swirled into the turbine section and/or after such of a combine cycle gas turbine electrical generation unit to improve the efficiency of the unit as described in United States Patents 8,671,696 , 9,376,933 and Ap # 15/443,692. Beyond electrical generation there is benefit in aircraft propulsion etc.. The technology is to increase thrust power output per unit of fuel with water or other volatile. Asked where is the analysis on claims of heard by me of 12 % less gas fuel to get electricity output ! The answer in my presentation.
Again asked where is the analysis on claims of heard by me of 12 % less gas fuel to get electricity output compared to combined cycle now in use and lower capital cost combined cycle units and efficiency of gas turbine electrical generator units 1 to 400 MW nearly the same which would greatly reduce electrical distribution losses and much lower startup shut down cost. This is a start ! Great for rig power, transportation marine, train combined cycle gas turbines. Fit in aircraft for fuel savings. At World Petroleum Congress heard +30 percent.
This document summarizes a student internship project on gas turbine performance simulation undertaken at Cranfield University. The project involved using Turbomatch software to simulate the off-design performance of 3 turbofan engines - CFM56-7B27, Rolls Royce Trent 1000, and Pratt & Whitney 4084. The student analyzed compressor maps, plotted performance parameters like thrust and SFC against turbine inlet temperature and ambient temperature, and compared results between 2 versions of Turbomatch software. The analysis provided insights into engine operation and limitations as well as improvements in the new Turbomatch version.
The document discusses gas exchange processes in internal combustion engines. It covers topics like supercharging, turbocharging, scavenging processes, compressors, turbines, and factors that influence the residual gas fraction. It provides details on different scavenging configurations for 2-stroke engines and the intake and exhaust processes in a 4-stroke engine. Diagrams are included to illustrate the various concepts.
Experimental validation of effect of equivalence ratio on detonation characte...ijmech
Experimental studies were carried out for using Propane as fuel for Pulse Detonation Engine application. In the present study Detonation Characteristics of Propane & Oxygen mixture at various equivalence ratios were presented. In these experiments Propane and Oxygen under regulated pressures were injected into a Detonation Tube from the head end using unlike impinging doublet injector. The fuel and oxidizer were allowed to mix and fill the tube. Subsequently, the mixture was ignited using a spark plug positioned close to the head end of the tube. The pressures generated due to the combustion of the mixtures were captured using five high frequency pressure transducers which were spaced 100mm apart on the detonation tube. Apart from these pressures, velocities of the combustion wave were computed using ‘time of flight’ method. These
tests were done for different equivalence ratios varying from 0.8 to 1.6 by varying the feeding pressure of
Propane. In the present study the performance of the combustion wave at different locations and effect of
equivalence ratios on detonation characteristics were presented. In addition effect of presence of obstacles in
the flow path i.e., Shchelkin spirals were also studied in reducing the Deflagration to Detonation Transition
(DDT) distance.
The CFD Analysis of Turbulence Characteristics in Combustion Chamber with Non...IOSR Journals
Abstract : Co-Axial jets have applications in areas where the mixing of two fluid jets are necessary, the two
fluid jets can be effectively mixed by producing the turbulence flow. Turbulence is a chaotic behavior of the fluid
particles that comes in to picture when the inertia force of the flow dominates the viscous force and it is
characterized by the Reynolds Number. Co-axial jets are effective in producing the turbulence. In the present
study the free compressible turbulent coaxial jet problem will be computed using CFD, and compare with
different non circular coaxial jets based on constant hydraulic diameter and mass flow rate. Turbulence
characteristics of combustion chamber with circular coaxial and non circular coaxial jets are determined and
compared.
Keywords: Coaxial Jet, Turbulence Modeling, Fuel injector, Combustion chamber.
The document discusses gas turbines and their components. It provides details about BHEL, an Indian company that manufactures gas turbine components including rotors. It describes the working of gas turbines, the Brayton cycle, components like compressors and turbines. It also discusses factors that affect gas turbine performance such as ambient temperature, pressure and humidity as well as technical parameters like pressure ratio, turbine inlet temperature and isentropic efficiency.
This document provides a review of research on using turbocharging to improve diesel engine performance and reduce exhaust emissions. It discusses how turbochargers work by using the engine's exhaust gases to power a turbine, which spins a compressor to increase the density of intake air entering the engine. This allows the engine to operate with higher volumetric efficiency. The document reviews several studies that have investigated how non-adiabatic (heat transfer) effects within the turbocharger can impact engine volumetric efficiency and increase turbo lag. Insulating the turbine is suggested as a way to reduce these impacts. The review examines models developed to represent heat transfer between turbocharger components and experimental work analyzing its effects on the engine charging process.
The presentation discusses variable cycle engines (VCE), a type of hybrid engine that aims to achieve supersonic speeds with high efficiency and low noise. A VCE can operate as both a turbofan and turbojet engine using variable geometry components like variable area bypass injectors and nozzles. These components allow the engine to vary its thrust, mass flow rate, and cycle to perform efficiently across subsonic, transonic, and supersonic flight. The presentation provides details on VCE configuration, working principles, effects of variable areas on performance parameters, and the development of VCE technology.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Leonard M. Andersen
Water Swirled Into Gas Turbine Tech
Caller Box 1529
New York, New York 10116, USA
914-237-7689
ABSTRACT
New technology covered in Ap # 20170306843
“METHOD AND APPARATUS FOR
INCREASING USEFUL ENERGY/THRUST OF A
GAS TURBINE ENGINE BY ONE OR MORE
ROTATING FLUID MOVING (AGITATOR)
PIECES DUE TO FORMATION OF A DEFINED
STEAM REGION” Filed: February 27, 2017
published October 26, 2017 . This new technology
has been developed with water into a flow of hot gas
in a swirling pattern most recently with a focus on
internal combustion engines , fired boiler stacks and,
water swirled into gas turbines combined cycles for
more fuel efficiency. The latest development has
pollution control with PM2.5 particulate. In
electrical generation the latest advance is to have a
fluid mover of a paddle nature moving a mass –
volume of optimally positioned spaced sized water
droplets in hot gas outward from a centerline into a
tire donut shaped volume space where said goes to
steam / pressurization. Such pressurization happens
making an extractive turbine turn which is connected
to an electrical generator. In fired boilers and internal
combustion engines the shaft of the fluid mover
would be vertical and extractive turbine would
normally be horizontal. The horizontal extractive
turbine would have water drops and combustion gas
leaving at about 120 C with less particulates exiting.
The work in new combined cycle gas turbines prior
to this is to at end of power turbine through blades
and/or a mechanism to put water droplets into the hot
thrust gas of 350 – 500 C going to steam in
concentrated volume. Said volume goes in a
steaming chamber. The energy is converted from
heat to steam pressurized increase in volume.
Increase in volume in the steaming chamber acts on
an extractive turbine connected to an electrical
generator. This could benefit from aforementioned.
The tire donut shape would be vertical. The
maintenance and operation of this is a fast moving
subject with in exhaust – stack gas plus 5 % per unit
fuel and in the case of water swirled into gas turbines
10 – 20 %. The motivation for the presentation is to
get discussion going. Power generation using new
way of water introduced in gas turbine combined
cycle manner maintenance and operation is
envisioned to be presented with more than one
speaker. A speaker on coal fired with experience of
use and, second on internal combustion engines
automotive / ship propulsion and fourth on new
combined cycle gas turbine
Analysis of Steam Zoning With Exhaust – Smoke Stack and Water Swirled Into Gas Turbine Technology Presented at Power Energy 2017-3191 Power & Energy Conference June 29, 2017 Charlotte, Updated. Was at Turbo Expo Oslo Norway June 2018 United States Patents 8,671,696 , 9,376,933 and one pending Ap 20170306843
This document provides an overview of different types of steam turbines used in maritime applications. It discusses the basic design and operation of impulse turbines, impulse-reaction turbines, and pressure compounded turbines. Impulse turbines only utilize changes in steam direction to turn the turbine, while impulse-reaction turbines also utilize pressure drops across the blades. Pressure compounded turbines split the overall pressure drop into multiple smaller stages to reduce steam velocities to practical levels for ship propulsion. The document also covers nozzle design and how it controls the expansion of steam to convert heat energy to kinetic energy for driving the turbine.
The document provides information about jet engine propulsion, including the major components and processes involved. It discusses the global momentum analysis and equations for jet engines. It also covers types of propulsion systems, classifications of jet engines, and the basic operation and components of jet engines such as the compressor, combustor, turbine, and nozzle. Key components and their functions are described, including how compressed air is mixed with fuel and ignited to produce thrust through exhaust exiting the nozzle.
Gas Turbine Engines-Shenyang Aerospace UniversityImdadul Haque
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This so called PPT for propulsion study for Shenyang Aerospace University. This PPT right protected by Dr. divinder K. Yadav. Its using in SAU by Lale. For all students of Aeronautical Engineering must memorize each & every words from this PPT. If you miss a single words you must fail in the Exam. Remember there is no chance to be creative or use sense you just need to use the power of memorizing.
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DESIGN AND ANALYSIS OF CONVERGENT DIVERGENT NOZZLE USING CFD
1. IN(Online): 4142-3453 February 2017 Issue
DESIGNANDANALYSISOFCONVERGENTDIVERGENT NOZZLE USINGCFD
Rama Thulasi1
, N. Jashuva 2
1
M.Tech (MECH)., Dept of Mech., Global College Of Engineering and Technology, Kadapa, Andhra Pradesh.
2
Assistant Professor, Dept of Mech, Global College Of Engineering and Technology, Kadapa, Andhra Pradesh.
Abstract- CFD is a branch of fluid mechanics that uses
numerical methods and algorithms to solve and analyze
problems that involve fluid flows. Computers are used to
perform the calculations required to simulate the interaction
of liquids and gases with surfaces defined by boundary
conditions. In this thesis, CFD analysis of flow within
Convergent-Divergent supersonic nozzle of different cross
sections rectangular, square and circular has been performed.
The analysis has been performed according to the shape of the
supersonic nozzle and keeping the same input conditions. Our
objective is to investigate the best suited nozzle which gives
high exit velocity among the different cross sections
considered. The application of these nozzles is mainly in
torpedos. The work is carried out in two stages: 1.Modeling
and analysis of flow for supersonic nozzles of different cross
sections.2.Prediction of best suited nozzle among the nozzles
considered. In this, initially modeling of the nozzles has been
done in CATIA and later on mesh generation and analysis
have been carried out in ANSYS FLUENT 14.5 and various
contours like velocity, pressure, temperature have been taken
and their variation according to different nozzles has been
studied.
1.INTRODUCTION
A nozzle is a device that is used to increase the velocity of a
flowing fluid. It does this by reducing the pressure.
CONVERGENT-DIVERGENT nozzle is designed for
attaining speeds that are greater than speed of sound. the
design of this nozzle came from the area-velocity relation
(dA/dV)=-(A/V)(1-M^2) M is the Mach number ( which
means ratio of local speed of flow to the local speed of
sound) A is area and V is velocity
The following information can be derived from the area-
velocity relation -
1. For incompressible flow limit, i.e. for M tends to zero, AV
= constant. This is the famous volume conservation equation
or continuity equation for incompressible flow.
2. For M < 1, a decrease in area results in increase of
velocity and vice vera. Therefore, the velocity increases in a
convergent duct and decreases in a Divergent duct. This
result for compressible subsonic flows is the same as that for
incompressible flow.
3. For M > 1, an increase in area results in increase of
velocity and vice versa, i.e. the velocity increases in a
divergent duct and decreases in a convergent duct. This is
directly opposite to the behavior of subsonic flow in
divergent and convergent ducts.
4. For M = 1, dA/A = 0, which implies that the location where
the Mach number is unity, the area of the passage is either
minimum or maximum. We can easily show that the
minimum in area is the only physically realistic solution. One
important point is that to attain supersonic speeds we have to
maintain favorable pressure ratios across the nozzle.
Taking the rectangular bent nozzle as reference and keeping
the inlet, throat and exit areas and the axis
length constant, three dimensional rectangular, square and
circular straight nozzles geometries were generated.
1.Square Shape:
2.Circular Shape:
2. IN(Online): 4142-3453 February 2017 Issue
3.Rectangular Shape
II LITERATURE SURVEY
JET ENGINE
A jet engine is a system for turning fuel into thrust (ahead
motion). The thrust is produced with the aid of action and
reaction a bit of physics additionally known as Newton’s 0.33
law of movement The pressure (movement) of the exhaust
gases pushing backward produces an same and opposite force
(response) known as thrust that powers the automobile ahead.
exactly the same principle pushes a skateboard ahead when you
kick backward along with your foot. In a jet engine, it's the
exhaust gas that gives the "kick".
Jet engine designs are regularly modified for non-aircraft
programs, as business gas turbines. these are utilized in electric
electricity generation, for powering water, natural gasoline, or
oil pumps, and supplying propulsion for ships and locomotives.
industrial gasoline turbines can create as much as 50,000 shaft
horsepower.
Precept of jet engine
The gasoline turbine operates on the Brayton cycle in which the
working fluid is a non-stop drift of air ingested into the engine’s
inlet. The air is first compressed by way of a compressor (duct
chamber) to a strain ratio of normally 10 to forty instances the
strain of the inlet airstream.
It then flows into a combustion chamber, where a steady move
of the hydrocarbon gas, in the shape of liquid spray droplets and
vapor or both, is added and burned at approximately consistent
strain.
This offers rise to a continuous stream of high-stress
combustion products whose common temperature is normally
from 980 to at least one,540 °C or higher.
This movement of gases flows via a exhaust nozzle, that is
connected by means of a compressor and combustion chamber
which extracts strength from the gasoline circulation to produce
thrust. due to the fact heat has been brought to the working fluid
at excessive pressure, the gasoline move that exits nozzle is
excessive.
The primary JET ENGINE-quick history OF EARLY JET
ENGINES SIR ISAAC NEWTON within the 18th century
changed into the first to theorize that a rearward-channeled
explosion could propel a gadget forward at a splendid price of
speed. This concept changed into primarily based on his third
law of motion. As the hot air blasts backwards via the nozzle the
aircraft moves forward. HENRI GIFFORD constructed an
airship which turned into powered by way of the primary
aircraft engine, a 3-horse electricity steam engine. It changed
into very heavy, too heavy to fly. In 1874, FELIX DE TEMPLE
built a monoplane that flew only a short hop down a hill with
the
assist of a coal fired steam engine. OTTO DAIMLER, within the
overdue 1800's invented the first fuel engine.
In 1894, American HIRAM MAXIM attempted to strength his
triple biplane with two coal fired steam engines. It best flew for
some seconds. The early steam engines had been powered by
way of heated coal and have been normally an awful lot too
heavy for flight.
American SAMUEL LANGLEY made model airplanes that
have been powered by way of steam engines. In 1896, he was
successful in flying an unmanned plane with a steam-powered
engine, referred to as the Aerodrome. It flew approximately 1
mile earlier than it ran out of steam. He then tried to construct a
full sized plane, the Aerodrome A, with a gasoline powered
engine. In 1903, it crashed at once after being launched from a
residence boat.
STYLES OF JET ENGINES
There are a huge range of different kinds of jet engines, all of
which acquire ahead thrust from the precept of jet propulsion.
reaching a excessive propulsive efficiency for a jet engine is
dependent on designing it in order that the exiting jet pace is not
significantly in excess of the flight speed. at the same time, the
amount of thrust generated is proportional to that very identical
speed extra that have to be minimized. This set of restrictive
requirements has caused the evolution of a big quantity of
specialized variations of the fundamental turbojet engine, every
tailored to reap a balance of suitable gas efficiency, low weight,
and compact size for responsibility in some band of the flight
pace altitude challenge spectrum.
There are two fundamental fashionable features characteristic of
all the one-of-a-kind engine sorts, however. First, so as to obtain
a excessive propulsive performance, the jet pace, or the rate of
the fuel circulate exiting the propulsion, is matched to the flight
pace of the plane slow aircraft have engines with low jet
velocities and fast aircraft have engines with excessive jet
velocities. 2nd, because of designing the jet velocity to match the
flight pace, the size of the propulsion varies inversely with the
flight speed of the aircraft slow plane have very large propulsors,
as, as an instance, the helicopter rotor and the relative length of
the propulsor decreases with growing design flight pace
turboprop propellers are fantastically small and turbofan
enthusiasts even smaller.
The primary idea of the turbojet engine is easy. Air taken in
from a gap within the the front of the engine is compressed to
a few to 12 instances its unique strain in compressor. gasoline
is added to the air and burned in a combustion chamber to
raise the temperature of the fluid aggregate to about 1,a
hundred°F to at least one,three hundred° F. The resulting hot
air is handed via a turbine, which drives the compressor. If the
turbine and compressor are green, the pressure on the turbine
discharge can be nearly two times the atmospheric strain, and
this excess stress is sent to the nozzle to provide a excessive-
pace flow of gas which produces a thrust.
full-size will increase in thrust can be received by way of
employing an afterburner. it's miles a second combustion
chamber placed after the turbine and earlier than the nozzle.
tremendous increases in thrust may be received by way of
using an afterburner. it is a 2nd combustion chamber placed
after the turbine and before the nozzle. The afterburner will
increase the temperature of the gasoline in advance of the
nozzle. The end result of this increase in temperature is an
growth of about 40 percent in thrust at takeoff and a much
larger percent at excessive speeds once the aircraft is inside
3. IN(Online): 4142-3453 February 2017 Issue
the air.
Fig 4: Turbojet engine
A turbofan engine has a big fan on the front, which sucks in
air. most of the air flows around the out of doors of the
engine, making it quieter and giving greater thrust at low
speeds. maximum of state-of-the-art airliners are powered by
means of turbofans. In a turbojet all the air getting into the
intake passes via the gasoline generator, which is composed
of the compressor, combustion chamber, and turbine. In a
turbofan engine simplest a portion of the incoming air goes
into the combustion chamber.
The remainder passes thru a fan, or low-pressure
compressor, and is ejected directly as a "bloodless" jet or
combined with the gas-generator exhaust to produce a "hot"
jet. The objective of this type of bypass system is to boom
thrust without growing gas consumption. It achieves this
with the aid of increasing the entire air-mass drift and
lowering the rate within the identical general strength
deliver.
A turboprop engine is a jet engine connected to a propeller.
The turbine on the again is became by using the new gases,
and this turns a shaft that drives the propeller.
a few small airliners and transport plane are powered by
means of turboprops. like the turbojet, the turboprop engine
includes a compressor, combustion chamber, and turbine, the
air and gasoline pressure is used to run the turbine, which
then creates strength to drive the compressor.
as compared with a turbojet engine, the turboprop has better
propulsion efficiency at flight speeds below approximately
500 miles per hour. current turboprop engines are ready with
propellers that have a smaller diameter but a bigger range of
blades for efficient operation at a great deal better flight
speeds. to house the higher flight speeds, the blades are
scimitar-shaped with swept-returned main edges at the blade
tips. Engines providing such propellers are called prop
fanatics. Max Mueller designed the first turboprop engine
that went into production in 1942.
Fig 5: Turbo prop engine
A ram jet engine is a tool from which beneficial thrust may
be obtained through growing a pace difference between the
atmosphere getting into the ram jet body and the identical
amount of air leaving the ram jet body. This speed distinction
among entrance and go out air is achieved via the addition of
heat to that part of the airstream flowing thru the ram jet
frame. Ramjets can not produce thrust at zero airspeed; they
can not move an aircraft from a standstill. A ramjet powered
car, consequently, calls for an assisted take-off like a rocket
assist to accelerate it to a pace wherein it begins to supply
thrust. Ramjets work most efficiently at supersonic speeds
around Mach 3 (2,284 mph; 3,675 km/h). This sort of engine
can function as much as speeds of Mach 6 (2,041.7 m/s; 7,350
km/h). they have got also been used successfully, although
now not efficiently, as tip jets on the stop of helicopter rotors.
Ramjets haven't any moving elements just like a valve less
pulsejet but they perform with non-stop combustion in place
of the collection of explosions that supply a pulsejet its feature
noise.
Fig 6: Ramjet engine
III. SHOCKWAVES
Whilst some thing reasons a noise, together with a door
lamming or a firecracker popping, it causes a pressure wave to
transport via the air, whilst this wave reaches us our ears
translate the sudden pressure change into the sound we listen.
The stress wave is honestly just air molecules bumping in
opposition to every different. The molecules normally simply
flow around randomly, moving this manner and that. while the
firecracker pops it releases excessive stress gasses that rush
outward, pushing in opposition to the air molecules. these
molecules in flip circulate outward and encounter others,
pushing them along to come upon yet more air molecules.
think of a bunch of balls lined up on a pool table. The cue ball
moves the first, inflicting it to transport and strike the second.
while it does the electricity of motion is transferred to the
second ball and the primary ball stops. Likewise, the second
ball moves the third, transfers power to it, and forestalls. on
this way the electricity passes from one ball to the alternative,
and this energy "wave" flows down the road of balls from the
primary to the closing. despite the fact that the gap from the
primary to closing ball can be high-quality, not one of the
individual balls movements very some distance. This is how
the pressure wave moves through the air, passing from
molecule to molecule. The wave is simply quite a few
4. IN(Online): 4142-3453 February 2017 Issue
molecules that are no longer shifting randomly, but are all
shifting within the identical direction on the identical time
till they stumble upon every other air molecule and pass
electricity to it. After the wave passes the air molecules cross
returned to randomly bumping into every other. As an item
actions via the air it pushes apart the air in its route. The
transferring air forms a stress wave that moves outward at
the velocity of sound. in the image beneath the arrow
categorised "pace of sound" represents the gap sound travels
at some point of the time of flight of the missiles.
Fig 7: Object moves through the air
The missile at the left is moving at 1/2 the rate of sound
(Mach zero.five). The stress waves created as it movements
via the ecosystem are transferring twice as rapid as the
missile and use up in all instructions. In all cases the stress
waves race in advance of the missile. every semicircle
suggests how some distance the sound wave has traveled
since the missile surpassed the numbered positions. notice
that the space between waves is shorter in front of the
missile than off to the aspect of the missile - the waves are
compressed ahead of the missile. but, they do not overlap to
generate a shock wave. in the center photograph the missile
is moving at the speed of sound. The pressure waves make
bigger outward at the speed of sound however they can not
pass beforehand of the missile. on the main tip of the missile
all waves are compressed so that they overlap, however they
use up commonly some other place so a surprise wave is not
propagated. within the proper hand image the missile is
moving quicker than the speed of sound. The strain wave
can't move as speedy as the missile so the missile races
beforehand of the strain waves. consequently all waves
moving outward from the missile's course combine to create
a excessive pressure conical "surprise wave" emanating from
the nose of the missile, moving outward thru the air at the
velocity of sound, like the wake of a ship moving thru water.
whilst this surprise wave reaches our ears we hear a "sonic
increase."
Simple Ramjets
It’s far this supersonic surprise wave that is essential to
ramjet air consumption functioning, and it turned into the
purpose of main complications within the layout of ramjets
that could work reliably. it's miles critical to understand that
the air molecules in this wave are shifting at the speed of
sound, and no faster.
The handiest air consumption design is only a hole tube with
a circular starting - a pipe. consider a pipe fixed to a
supersonic plane or rocket. whilst the pipe is propelled via
the air at supersonic speeds the threshold of the opening
pushes air molecules out of the manner, forming a shock
wave. at the out of doors fringe of the pipe the surprise wave
actions outwardly similar to it does around the nose of a
supersonic bullet. but, at the inside of the tube the surprise
waves from all around the starting converge, as proven by
way of the dashed strains. The air molecules moving far from
the internal fringe of the outlet run into different molecules
moving inward and the stress wave can move no farther.
pressure builds up at the back of the shock wave, compressing
the air within the tube and slowing the fee at which it flows
thru the tube.
Fig 8: Shock waves in simple ramjet
Now we want to reconsider the relative motions of the tube
and the atmosphere. it's far the tube that is shifting faster than
the speed of sound, and the air is standing nonetheless.
however, the idea of relativity permits us to consider the
situation as if the tube become status still and the air was
rushing by using at supersonic speeds.
As stress rises in the tube air temperature also rises. for the
reason that inner walls of the tube save you outward growth of
the air in the tube, and the air speeding in the the front
prevents get away that way, the hot high pressure gasses can
break out most effective from the rear wherein they extend
unexpectedly and return to the temperature and pressure of the
encircling air. however, this occurs handiest while the tube is
shifting through the air very unexpectedly.
whilst the new gasses get away at the rear of the tube they
may be accelerated as the stress drops. you see the same
component whilst water escapes via the quit of your garden
hose. The better the water stress inside the hose the faster the
water flows from the hose.
The higher the stress in the ramjet tube, the quicker the gasses
break out on the rear. because the gasses are heated as they
may be compressed into the tube, the stress increases even
more and that they get away the rear even quicker.
5. IN(Online): 4142-3453 February 2017 Issue
IV. RESULTS
Fig 21: High pressure in combustion chamber
Fig 37: Meshed model of rectangular shaped convergent-
divergent nozzle
Fig 38: Pressure distribution on rectangular shaped
convergent-divergent nozzle
Fig 39: Velocity distribution on rectangular shaped
convergent-divergent nozzle
V.CONCLUSION
After successfully completing this simulation of a layout
created, the decisions have been subsequently restricted into
the following factors.
FLUENT evaluation has been done on Convergent-
Divergent nozzles of different pass sections like
square, square and rectangle for Ram Jet Engine by
way of using ANSYS 14.5.
In parent 31, 35 and 39 speed distribution of round,
square and rectangular formed nozzles are shown
respectively.
As the speed and mass go with the flow fee of air
will increase earlier than the diffuser the speed of the
jet also will increase
It's miles sincerely visible the rate is increasing along
with the duration of the nozzle. Because of stunning
within the nozzle, the speed reduced for some time
however later started out to growth because the fluid
accelerated via the divergent component.
Stress gradually reduced along the duration of the
nozzle except a moderate upward thrust for the
duration of the stunning. however, the rise changed
into now not huge comparing to the total fall in
strain. consistent with Bernoulli’s equation, pressure
lower as pace boom alongside growth sector.
In discern 32, 36 and 40 represents temperature
distribution in C-D nozzle of Ram Jet engine. Right
here, the most temperature acquired at the quit of the
nozzle and at the throat phase we are able to examine
the variation of temperature.
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2. Hesselgreaves, J.E., Compact Heat Exchangers, Pergamon
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3. Yunus, A. Çengel. "Heat and Mass Transfer." McGrawHill,
New York (2007).
4. Tuckerman D.B., and Pease R.F., 1981, High-performance
heat sinking for VLSI, IEEE Electron Device Letters, IEEE,
2(5), pp. 126-129.
5. Ravigururajan, T. S., Cuta, J., McDonald, C. E., & Drost,
M. K. (1996). Singlephase flow thermal performance
characteristics of a parallel micro-channel heat exchanger
(No. CONF-960815). American Society of Mechanical
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AUTHORS PROFILE
RAMA THULASI he is pursuing M.Tech
(Mechnical) at Global College Of Engineering
and Technology, Kadapa, Andhra Pradesh..
Mr. N. Jashuva,M.Tech. Assistant Professor at
Global College Of Engineering and Technology,
Kadapa, Andhra Pradesh.