The opposed jet burner configuration that has been constructed in this experiment has been proven capable of producing and sustaining a stable stagnation flame. Despite the presence of a double helix shaped silicon carbide heating rod that resides in the top burner, the effect that it has on the flow and the resulting imposed velocity gradient on the stagnation flame did not cause a deviation from previously performed experimental results for a Methane stagnation flame at φ=0.7. However, this only holds true if the heating rod is positioned in just the right location, in the center of the top burner and at the right angle so it is parallel to the inner walls of the burner. Now that the combustion rig has been constructed and is capable of sustaining stable stagnation flames, the groundwork has been laid to begin testing ignition of fuel air mixtures through the heating of the air flow through the top burner. Future studies will need to be done to quantify the effect of the increased flow rate that will be induced by heating the flow through the top burner, and the necessary flow rate adjustments to ensure the momentum of the top and bottom flow remain equal so that a stable stagnation flame can still be produced. Ultimately, once the ignition of gaseous fuels has been achieved by this system and is calibrated to sustain stagnation flames consistent with previously published experimental data of laminar flame speeds, the rig will once more be modified to allow for the preheating of liquid fuels through the bottom burner, with the end goal of achieving ignition of various cracked states of JP-7.
FINAL Report for Development of Enclosed Combustion Right for SCRAMJET Fuel S...Dan Martin
This document describes the development of an enclosed combustion rig to study ignition of fuels for scramjet engines. The rig uses an opposed jet burner configuration to produce a stable stagnation flame for experimentation. A double helix silicon carbide heating rod is inserted into the top burner to heat the opposing air flow and achieve ignition of fuel-air mixtures passing through the bottom burner. The rig has been tested and can sustain stable stagnation flames. Future work will quantify the effects of heated flow and calibrate the rig to ignite fuels and measure flame properties like ignition temperature, propagation speed, and extinction strain rate. This will provide data on cracked states of jet fuel to inform scramjet combustion design.
The primary reformer is where natural gas and steam undergo endothermic reforming reactions to produce hydrogen. Approximately 80% of an ammonia plant's fuel is consumed in the primary reformer burners heating these reactions. To optimize performance, the furnace draft, oxygen content in flue gases, and reformer outlet temperature must be maintained within optimal ranges. High or low draft, excess or insufficient oxygen, and temperatures too low or too high can all decrease efficiency. Careful control of these factors is required for efficient and safe primary reformer operation.
ER Publication,
IJETR, IJMCTR,
Journals,
International Journals,
High Impact Journals,
Monthly Journal,
Good quality Journals,
Research,
Research Papers,
Research Article,
Free Journals, Open access Journals,
erpublication.org,
Engineering Journal,
Science Journals,
This document discusses key topics related to optimizing ammonia plant performance:
1) Carbon formation in primary reformers can be minimized by maintaining proper steam-to-carbon ratios and avoiding temperature excursions. Tube wall temperatures, pressure drop, and methane approach to equilibrium should be monitored.
2) Flow distribution in catalytic reactors is important to ensure proper catalyst utilization. Poor distribution can increase costs by reducing conversion efficiency.
3) Operational upsets and transient conditions like startups and shutdowns can lead to carbon formation if not carefully controlled. Sulfur poisoning from even small amounts in feed can significantly impact temperatures.
Effect of Pilot Flame Instabilities on Pressure in Case of Assisted CombustionDiego Scarpa
This document examines the effect of pilot flame instabilities on pressure in assisted combustion systems. It analyzes combustion in the annular chamber of an Ansaldo-Siemens V64.3A gas turbine. Numerical simulations were performed to characterize mixing and temperature distributions at the outlet of the turbine's premixing vortex. The results show non-uniform mixing and worsening distribution with increasing load. Modifications to the injection geometry and flow parameters may help optimize the reaction process and stabilize combustion over a wide load range.
Yogesh Kumar Tripathi is a chemical engineer seeking a position in a company that will allow him to develop his skills. He has over 10 years of experience in the cement industry, having worked at JK Lakshmi Cement, JP Super Cement, and currently at Maratha Ambuja Cement. He has expertise in kiln operations and maintenance, and has experience implementing alternative fuel systems. He holds an AMIE in chemical engineering and has achieved commissioning of new production lines and reducing manufacturing costs.
Gas turbines are internal combustion engines that produce power by burning an air-fuel mixture to spin a turbine and drive a generator. They work by compressing air, igniting the air-fuel mixture at high temperatures, spinning turbine blades with the hot gases, and using the spinning turbine to power a generator and produce electricity. Gas turbines can operate on a wide range of gaseous, liquid, and solid fuels. Fuel injectors introduce fuel into the combustion chamber in atomized form. Emissions like CO, NOx, and UHC are controlled through techniques like optimized fuel-air ratios, improved mixing, and exhaust gas recirculation. CFD analysis is used to study internal cooling schemes in turbine blades.
This document discusses supercritical technology used in power plants. It begins with an overview of the basic Rankine cycle used in conventional power plants. It then discusses how operating above the critical point of water in a supercritical Rankine cycle can significantly improve efficiency. Key points include operating at pressures above 221.2 bar and temperatures above 374.15°C to remain in the supercritical phase. Modern materials allow higher turbine inlet temperatures up to 700°C. Boiler and turbine design must account for the high pressures and temperatures in supercritical systems.
FINAL Report for Development of Enclosed Combustion Right for SCRAMJET Fuel S...Dan Martin
This document describes the development of an enclosed combustion rig to study ignition of fuels for scramjet engines. The rig uses an opposed jet burner configuration to produce a stable stagnation flame for experimentation. A double helix silicon carbide heating rod is inserted into the top burner to heat the opposing air flow and achieve ignition of fuel-air mixtures passing through the bottom burner. The rig has been tested and can sustain stable stagnation flames. Future work will quantify the effects of heated flow and calibrate the rig to ignite fuels and measure flame properties like ignition temperature, propagation speed, and extinction strain rate. This will provide data on cracked states of jet fuel to inform scramjet combustion design.
The primary reformer is where natural gas and steam undergo endothermic reforming reactions to produce hydrogen. Approximately 80% of an ammonia plant's fuel is consumed in the primary reformer burners heating these reactions. To optimize performance, the furnace draft, oxygen content in flue gases, and reformer outlet temperature must be maintained within optimal ranges. High or low draft, excess or insufficient oxygen, and temperatures too low or too high can all decrease efficiency. Careful control of these factors is required for efficient and safe primary reformer operation.
ER Publication,
IJETR, IJMCTR,
Journals,
International Journals,
High Impact Journals,
Monthly Journal,
Good quality Journals,
Research,
Research Papers,
Research Article,
Free Journals, Open access Journals,
erpublication.org,
Engineering Journal,
Science Journals,
This document discusses key topics related to optimizing ammonia plant performance:
1) Carbon formation in primary reformers can be minimized by maintaining proper steam-to-carbon ratios and avoiding temperature excursions. Tube wall temperatures, pressure drop, and methane approach to equilibrium should be monitored.
2) Flow distribution in catalytic reactors is important to ensure proper catalyst utilization. Poor distribution can increase costs by reducing conversion efficiency.
3) Operational upsets and transient conditions like startups and shutdowns can lead to carbon formation if not carefully controlled. Sulfur poisoning from even small amounts in feed can significantly impact temperatures.
Effect of Pilot Flame Instabilities on Pressure in Case of Assisted CombustionDiego Scarpa
This document examines the effect of pilot flame instabilities on pressure in assisted combustion systems. It analyzes combustion in the annular chamber of an Ansaldo-Siemens V64.3A gas turbine. Numerical simulations were performed to characterize mixing and temperature distributions at the outlet of the turbine's premixing vortex. The results show non-uniform mixing and worsening distribution with increasing load. Modifications to the injection geometry and flow parameters may help optimize the reaction process and stabilize combustion over a wide load range.
Yogesh Kumar Tripathi is a chemical engineer seeking a position in a company that will allow him to develop his skills. He has over 10 years of experience in the cement industry, having worked at JK Lakshmi Cement, JP Super Cement, and currently at Maratha Ambuja Cement. He has expertise in kiln operations and maintenance, and has experience implementing alternative fuel systems. He holds an AMIE in chemical engineering and has achieved commissioning of new production lines and reducing manufacturing costs.
Gas turbines are internal combustion engines that produce power by burning an air-fuel mixture to spin a turbine and drive a generator. They work by compressing air, igniting the air-fuel mixture at high temperatures, spinning turbine blades with the hot gases, and using the spinning turbine to power a generator and produce electricity. Gas turbines can operate on a wide range of gaseous, liquid, and solid fuels. Fuel injectors introduce fuel into the combustion chamber in atomized form. Emissions like CO, NOx, and UHC are controlled through techniques like optimized fuel-air ratios, improved mixing, and exhaust gas recirculation. CFD analysis is used to study internal cooling schemes in turbine blades.
This document discusses supercritical technology used in power plants. It begins with an overview of the basic Rankine cycle used in conventional power plants. It then discusses how operating above the critical point of water in a supercritical Rankine cycle can significantly improve efficiency. Key points include operating at pressures above 221.2 bar and temperatures above 374.15°C to remain in the supercritical phase. Modern materials allow higher turbine inlet temperatures up to 700°C. Boiler and turbine design must account for the high pressures and temperatures in supercritical systems.
KAMI Foundation was founded in 2009 by Michel Jobin to promote environmental preservation and provide alternative fuels in Haiti. In April 2009, Michel introduced kerosene stoves to villagers in Terrier-Rouge as a safer alternative to charcoal. Local manufacturers then built 10 prototype stoves. 169 villagers, including 59 women, were trained on safely using the new stoves. The stoves are working well and people can now cook indoors."
KAMI is a non-profit organization that operates programs in Haiti, including manufacturing affordable kerosene stoves as alternatives to wood and charcoal, encouraging jatropha plant cultivation for biodiesel production, and providing environmental education. The document provides updates on KAMI's jatropha plantations and stove production, recognizes supporters of the organization, and outlines plans to establish "Les Entreprises KAMI" as a Haitian-owned and operated self-sustaining business. It also introduces Marie-Belle, a woman who benefits from KAMI's programs, and invites readers to support KAMI's continued work.
A case study on bio fuel stove technology jatropha as a bio fuelAshok Yadav
This document presents a case study on using Jatropha oil as a biofuel for stoves in Nepal. It describes the physical properties of Jatropha oil compared to kerosene. The objectives were to test using pure Jatropha oil for burning. A wick stove was modified with multiple cotton wicks and a 1.5 liter fuel tank. Testing showed the fuel transported well for the first 5 cm but slowed beyond 7 cm, demonstrating pure Jatropha oil's viability as stove fuel without blending with kerosene.
COMPARATIVE STUDY OF FULL JOURNAL BEARING WITH BIO LUBRICANTS – JATROPHA OIL,...IAEME Publication
The present study was carried with an aim of checking the feasibility of usage of bio-lubricants as a lubricant in hydrodynamic full journal bearing. Three bio-lubricants Castor oil, Neem oil, Jatropha oil and mineral oil SAE 20W50 is used alternatively to check the output of the journal bearing
operating parameters.
This document presents the design and analysis of a scramjet engine. The author uses quasi-one-dimensional equations to model the compressible flow and combustion within the engine. Performance is estimated using computational modeling of the inlet, combustor, and nozzle. Initial results show a thrust of nearly 405 kN and specific impulse of 174 seconds. Further analysis of the combustion chamber and boundary layers is recommended.
The Jatropha System: An Integrated Approach of Rural Development QZ1
This document provides an overview of the Jatropha system, an integrated approach to rural development using Jatropha curcas L., a plant native to Central America. The system was revived in Germany and other countries to use Jatropha seeds for fuel. The document describes the strategy for implementing the system at the local, national, and international levels. It also details the botany of Jatropha curcas L., its varieties, distribution, agricultural practices for growing it as hedges and in plantations, yields, and methods for improving yields.
The document traces the development of shredder machines across six generations. The first generation used belts that could wear out over time. The second generation used plastic gears that were prone to breaking. The third generation used metal sprockets that provided quiet and efficient operation. The fourth generation used metal gears but still produced noise at high speeds. The fifth generation used alloy steel and CNC machining to reduce wear and ensure quality. The sixth generation are modern machines that can shred various materials and have features like automatic shut-off for safety and environmental protection.
This document summarizes the design of a scramjet engine for Mach 5 flight. It outlines the benefits and challenges of scramjet technology, including that it is air-breathing and has no moving parts but requires special heat-resistant materials. The document then details the design process, which used a quasi-1D flow analysis method to model the inlet, combustor, and nozzle for Mach 5 flight at 15 km altitude. The results showed thrust of 405 kN, specific impulse of 174 seconds, and efficiencies around 0.8-0.9. However, the engine would only be viable installed on a large vehicle and requires improved combustion modeling for higher supersonic speeds.
Friction Stir welding combine the action of frictional heating and mechanical deformation due to a rotating tool. The advantages of Friction Stir welding over arc welding is as follows:-
1) High quality weld can be achieved
2) Absence of solidification cracking
3) Lower apparent energy input
4) Less distortion and residual stress
Electricity generation from speed breaker and piezo tilesAbhishek Shukla
This document discusses mechatronics and describes different mechanisms that can be used to generate electricity from speed breakers, including rack pinion, spring coil, and crankshaft mechanisms. It focuses on using a rack pinion mechanism to power an alternator and generate electricity from passing vehicles that can be stored in batteries and used for street lights. The document outlines the advantages of this system, such as low-cost electricity production, and proposes future applications like enhancing efficiency and powering heavier vehicles.
This document provides an overview of friction stir welding (FSW). It describes FSW as a solid-state welding process that uses friction and mechanical stirring to join materials without melting. Key points include: FSW uses a rotating tool to generate frictional heat and plastically deform the materials, leaving a solid phase bond; important parameters are tool rotation/travel speeds and geometry; FSW eliminates issues like porosity and shrinkage seen in fusion welding. Applications include aerospace, transportation, industrial structures, and shipbuilding.
The document discusses different types of clutches used in vehicle transmissions. It defines a clutch as a mechanical device that engages and disengages power transmission between driving and driven shafts. The main types described are friction clutches (single plate, multi-plate, cone), centrifugal clutch, electromagnetic clutch, vacuum clutch, and hydraulic clutch. For each type, the key components and operating principles are explained. Friction clutches use pressure plates and clutch plates or cones to transfer torque via friction when engaged and allow freewheeling when disengaged. Centrifugal, electromagnetic, vacuum and hydraulic clutches use alternative mechanical or fluid-based actuation methods rather than manual control.
Friction stir welding is a solid state joining process that uses a rotating cylindrical tool to join two facing workpieces without melting them. As the non-consumable tool made of highly wear resistant material is rotated and slowly plunged into the material to be joined, friction generated between the shoulder and pin of the tool and the workpieces produces sufficient heat to cause the material to soften without reaching its melting point. This allows it to be joined by mechanical mixing/forging of the material in the plastic state. Three main zones are affected - the shoulder affected zone, pin affected zone, and thermo-mechanically affected zone. Heat is generated primarily through friction at the tool shoulder and plastic deformation. Material flow occurs as material is
The document presents information about scramjet engines. It discusses the history of scramjet development from World War II to recent test flights reaching Mach 10 speeds. The key components of a scramjet engine are described as a converging inlet to compress incoming air, a combustor where fuel is burned, and a diverging nozzle to accelerate the heated air and produce thrust. Scramjets differ from other jet engines by not using rotating components for compression and relying on high flight speeds to compress air before combustion. Potential applications include hypersonic aircraft that could reduce intercontinental flight times to under 90 minutes.
GENERATION OF ELECTRICITY THROUGH SPEED BREAKERSamiullah Kakar
This document describes a project to generate electricity from speed breakers on roads. As vehicles pass over speed breakers, kinetic energy is wasted through heat and friction. This project aims to convert that wasted energy into electrical energy. It proposes installing movable speed breakers connected to a rack and pinion mechanism to convert vertical motion into rotational motion. This rotation would generate electricity using standard generators. The document outlines the working principle, components, advantages, and scope of the project. It aims to provide a sustainable energy source by tapping into kinetic energy from traffic on busy roads.
This document discusses power generating shock absorbers that can convert the up and down movement of a vehicle's suspension into electricity. It describes two types of regenerative shock absorbers - linear and rotary - and explains their construction and operating principles. Road tests on a Chevrolet Suburban found the system generated electricity without significantly affecting vehicle momentum. While costly and complex, regenerative shock absorbers could improve fuel efficiency by 2-10% depending on road conditions and allow for energy recovery typically not possible with conventional braking systems. Further research aims to optimize design and test effectiveness in additional vehicle types.
1) The document discusses scramjet engines, which use supersonic combustion of fuel and air to produce thrust without needing liquid oxygen tanks.
2) Scramjets have components like converging inlets, combustors, and diverging nozzles. They work by compressing incoming supersonic air and injecting fuel for combustion.
3) Potential applications include hypersonic passenger planes traveling at 15 times the speed of sound and scramjet-powered missiles. Recent programs demonstrate scramjet flights up to Mach 9.6. Scramjets could enable cheaper access to space.
This document summarizes friction stir welding (FSW), including its working principle, microstructure analysis, tool design, process parameters, advantages, challenges, and applications. FSW is a solid state welding technique that uses a rotating tool to generate frictional heat and mechanically deform aluminum alloys below their melting point. It produces high quality welds with improved mechanical properties compared to fusion welding. Main applications are in shipbuilding, aerospace, and automotive industries.
This document discusses scramjet inlets, which are a critical component of scramjet engines suitable for sustained hypersonic flight. Scramjet inlets must compress supersonic incoming air for combustion while minimizing losses. Different inlet designs achieve varying levels of compression efficiency. The document examines inlet types, desired compression levels, and presents a design example of a 3D scramjet inlet intended to operate between Mach 6-12 for access to space. Key challenges for scramjet inlets include achieving sufficient compression while minimizing shock losses and heating at high flight speeds.
The blowoff limits and flashback limits for different diameter to length rati...Jameel Tawfiq
A 129 kWh swirl gas burner was used, where the effect of the burner geometry on the operation window was studied. Using LPG. The length of the burner edge was studied by taking three values of length (5 cm, 10 cm and 15 cm) which represent the ratio (1,2 and 3) to the diameter of the burner respectively. To enhance the combustion stability a swirl vane guide was used to obtain swirl flow and improve the flame structure. The result show that the increase in length of burner neck will decrease the swirl coherent structure and turn the flow to diffusion flow which increase the ability to have boundary layer flashback. However with the limit of burner used, increasing the length of burner neck gives a good result in blowoff side by bush it to leaner limits around ɸ=0.38 but in term of flashback it will bring it to leaner limits too, which is not preferable.. Although, this improvement is linked to the fuel type in first place but the flow structure has a significant impact on flame stability.
KAMI Foundation was founded in 2009 by Michel Jobin to promote environmental preservation and provide alternative fuels in Haiti. In April 2009, Michel introduced kerosene stoves to villagers in Terrier-Rouge as a safer alternative to charcoal. Local manufacturers then built 10 prototype stoves. 169 villagers, including 59 women, were trained on safely using the new stoves. The stoves are working well and people can now cook indoors."
KAMI is a non-profit organization that operates programs in Haiti, including manufacturing affordable kerosene stoves as alternatives to wood and charcoal, encouraging jatropha plant cultivation for biodiesel production, and providing environmental education. The document provides updates on KAMI's jatropha plantations and stove production, recognizes supporters of the organization, and outlines plans to establish "Les Entreprises KAMI" as a Haitian-owned and operated self-sustaining business. It also introduces Marie-Belle, a woman who benefits from KAMI's programs, and invites readers to support KAMI's continued work.
A case study on bio fuel stove technology jatropha as a bio fuelAshok Yadav
This document presents a case study on using Jatropha oil as a biofuel for stoves in Nepal. It describes the physical properties of Jatropha oil compared to kerosene. The objectives were to test using pure Jatropha oil for burning. A wick stove was modified with multiple cotton wicks and a 1.5 liter fuel tank. Testing showed the fuel transported well for the first 5 cm but slowed beyond 7 cm, demonstrating pure Jatropha oil's viability as stove fuel without blending with kerosene.
COMPARATIVE STUDY OF FULL JOURNAL BEARING WITH BIO LUBRICANTS – JATROPHA OIL,...IAEME Publication
The present study was carried with an aim of checking the feasibility of usage of bio-lubricants as a lubricant in hydrodynamic full journal bearing. Three bio-lubricants Castor oil, Neem oil, Jatropha oil and mineral oil SAE 20W50 is used alternatively to check the output of the journal bearing
operating parameters.
This document presents the design and analysis of a scramjet engine. The author uses quasi-one-dimensional equations to model the compressible flow and combustion within the engine. Performance is estimated using computational modeling of the inlet, combustor, and nozzle. Initial results show a thrust of nearly 405 kN and specific impulse of 174 seconds. Further analysis of the combustion chamber and boundary layers is recommended.
The Jatropha System: An Integrated Approach of Rural Development QZ1
This document provides an overview of the Jatropha system, an integrated approach to rural development using Jatropha curcas L., a plant native to Central America. The system was revived in Germany and other countries to use Jatropha seeds for fuel. The document describes the strategy for implementing the system at the local, national, and international levels. It also details the botany of Jatropha curcas L., its varieties, distribution, agricultural practices for growing it as hedges and in plantations, yields, and methods for improving yields.
The document traces the development of shredder machines across six generations. The first generation used belts that could wear out over time. The second generation used plastic gears that were prone to breaking. The third generation used metal sprockets that provided quiet and efficient operation. The fourth generation used metal gears but still produced noise at high speeds. The fifth generation used alloy steel and CNC machining to reduce wear and ensure quality. The sixth generation are modern machines that can shred various materials and have features like automatic shut-off for safety and environmental protection.
This document summarizes the design of a scramjet engine for Mach 5 flight. It outlines the benefits and challenges of scramjet technology, including that it is air-breathing and has no moving parts but requires special heat-resistant materials. The document then details the design process, which used a quasi-1D flow analysis method to model the inlet, combustor, and nozzle for Mach 5 flight at 15 km altitude. The results showed thrust of 405 kN, specific impulse of 174 seconds, and efficiencies around 0.8-0.9. However, the engine would only be viable installed on a large vehicle and requires improved combustion modeling for higher supersonic speeds.
Friction Stir welding combine the action of frictional heating and mechanical deformation due to a rotating tool. The advantages of Friction Stir welding over arc welding is as follows:-
1) High quality weld can be achieved
2) Absence of solidification cracking
3) Lower apparent energy input
4) Less distortion and residual stress
Electricity generation from speed breaker and piezo tilesAbhishek Shukla
This document discusses mechatronics and describes different mechanisms that can be used to generate electricity from speed breakers, including rack pinion, spring coil, and crankshaft mechanisms. It focuses on using a rack pinion mechanism to power an alternator and generate electricity from passing vehicles that can be stored in batteries and used for street lights. The document outlines the advantages of this system, such as low-cost electricity production, and proposes future applications like enhancing efficiency and powering heavier vehicles.
This document provides an overview of friction stir welding (FSW). It describes FSW as a solid-state welding process that uses friction and mechanical stirring to join materials without melting. Key points include: FSW uses a rotating tool to generate frictional heat and plastically deform the materials, leaving a solid phase bond; important parameters are tool rotation/travel speeds and geometry; FSW eliminates issues like porosity and shrinkage seen in fusion welding. Applications include aerospace, transportation, industrial structures, and shipbuilding.
The document discusses different types of clutches used in vehicle transmissions. It defines a clutch as a mechanical device that engages and disengages power transmission between driving and driven shafts. The main types described are friction clutches (single plate, multi-plate, cone), centrifugal clutch, electromagnetic clutch, vacuum clutch, and hydraulic clutch. For each type, the key components and operating principles are explained. Friction clutches use pressure plates and clutch plates or cones to transfer torque via friction when engaged and allow freewheeling when disengaged. Centrifugal, electromagnetic, vacuum and hydraulic clutches use alternative mechanical or fluid-based actuation methods rather than manual control.
Friction stir welding is a solid state joining process that uses a rotating cylindrical tool to join two facing workpieces without melting them. As the non-consumable tool made of highly wear resistant material is rotated and slowly plunged into the material to be joined, friction generated between the shoulder and pin of the tool and the workpieces produces sufficient heat to cause the material to soften without reaching its melting point. This allows it to be joined by mechanical mixing/forging of the material in the plastic state. Three main zones are affected - the shoulder affected zone, pin affected zone, and thermo-mechanically affected zone. Heat is generated primarily through friction at the tool shoulder and plastic deformation. Material flow occurs as material is
The document presents information about scramjet engines. It discusses the history of scramjet development from World War II to recent test flights reaching Mach 10 speeds. The key components of a scramjet engine are described as a converging inlet to compress incoming air, a combustor where fuel is burned, and a diverging nozzle to accelerate the heated air and produce thrust. Scramjets differ from other jet engines by not using rotating components for compression and relying on high flight speeds to compress air before combustion. Potential applications include hypersonic aircraft that could reduce intercontinental flight times to under 90 minutes.
GENERATION OF ELECTRICITY THROUGH SPEED BREAKERSamiullah Kakar
This document describes a project to generate electricity from speed breakers on roads. As vehicles pass over speed breakers, kinetic energy is wasted through heat and friction. This project aims to convert that wasted energy into electrical energy. It proposes installing movable speed breakers connected to a rack and pinion mechanism to convert vertical motion into rotational motion. This rotation would generate electricity using standard generators. The document outlines the working principle, components, advantages, and scope of the project. It aims to provide a sustainable energy source by tapping into kinetic energy from traffic on busy roads.
This document discusses power generating shock absorbers that can convert the up and down movement of a vehicle's suspension into electricity. It describes two types of regenerative shock absorbers - linear and rotary - and explains their construction and operating principles. Road tests on a Chevrolet Suburban found the system generated electricity without significantly affecting vehicle momentum. While costly and complex, regenerative shock absorbers could improve fuel efficiency by 2-10% depending on road conditions and allow for energy recovery typically not possible with conventional braking systems. Further research aims to optimize design and test effectiveness in additional vehicle types.
1) The document discusses scramjet engines, which use supersonic combustion of fuel and air to produce thrust without needing liquid oxygen tanks.
2) Scramjets have components like converging inlets, combustors, and diverging nozzles. They work by compressing incoming supersonic air and injecting fuel for combustion.
3) Potential applications include hypersonic passenger planes traveling at 15 times the speed of sound and scramjet-powered missiles. Recent programs demonstrate scramjet flights up to Mach 9.6. Scramjets could enable cheaper access to space.
This document summarizes friction stir welding (FSW), including its working principle, microstructure analysis, tool design, process parameters, advantages, challenges, and applications. FSW is a solid state welding technique that uses a rotating tool to generate frictional heat and mechanically deform aluminum alloys below their melting point. It produces high quality welds with improved mechanical properties compared to fusion welding. Main applications are in shipbuilding, aerospace, and automotive industries.
This document discusses scramjet inlets, which are a critical component of scramjet engines suitable for sustained hypersonic flight. Scramjet inlets must compress supersonic incoming air for combustion while minimizing losses. Different inlet designs achieve varying levels of compression efficiency. The document examines inlet types, desired compression levels, and presents a design example of a 3D scramjet inlet intended to operate between Mach 6-12 for access to space. Key challenges for scramjet inlets include achieving sufficient compression while minimizing shock losses and heating at high flight speeds.
The blowoff limits and flashback limits for different diameter to length rati...Jameel Tawfiq
A 129 kWh swirl gas burner was used, where the effect of the burner geometry on the operation window was studied. Using LPG. The length of the burner edge was studied by taking three values of length (5 cm, 10 cm and 15 cm) which represent the ratio (1,2 and 3) to the diameter of the burner respectively. To enhance the combustion stability a swirl vane guide was used to obtain swirl flow and improve the flame structure. The result show that the increase in length of burner neck will decrease the swirl coherent structure and turn the flow to diffusion flow which increase the ability to have boundary layer flashback. However with the limit of burner used, increasing the length of burner neck gives a good result in blowoff side by bush it to leaner limits around ɸ=0.38 but in term of flashback it will bring it to leaner limits too, which is not preferable.. Although, this improvement is linked to the fuel type in first place but the flow structure has a significant impact on flame stability.
A furnace convection section model was developed to analyze why furnaces at an ethylene plant were underutilized. Analysis of furnace operation history and an on-site model validated with plant data identified that throughput was limited by high metal temperatures in the convection section. A test run using the model increased furnace throughput by 20% and identified bottlenecks. Recommendations to introduce steam flow helped control temperatures and further increase capacity.
This document summarizes the numerical analysis of different parallel plate heat sink designs for electronic cooling applications. It discusses:
1) The simulation of a baseline heat sink case and a shielded heat sink within a chimney structure to compare heat transfer performance. The shielded case showed a 50% improvement in heat transfer.
2) The addition of a cross-cut modification to the heat sink, which was modeled using two turbulence models. This cross-cut design showed an average 17% increase in heat transfer compared to the shielded straight fin case.
3) The modeling of the cross-cut heat sink within a pumping system to induce forced convection. A pressure difference between the cross-cut and outlet was
Ring-Formation-in-Rotary-Kilns of cement plantSaurabhVyAs34
- Rings forming in rotary kilns used for cement production can cause shutdowns costing over 150,000 euros. Numerical modeling revealed rings form where radiative heat transfer is highest, overheating the material and causing it to stick to walls.
- Increasing secondary air injection was proposed to cool oven surfaces and counteract ring formation. Experimental validation showed this solution effectively prevented unscheduled shutdowns, saving five figures monthly.
- A computational fluid dynamics model of an empty kiln was developed to analyze temperature profiles and understand ring formation mechanisms without modeling the complex moving bed. Increasing air-fuel ratio reduced hotspot temperatures predicted to cause ring formation.
Soot Blowing Optimization- Field ExperiencePooja Agarwal
The document discusses soot blower optimization strategies implemented at Jindal Power Limited coal-fired power plants. Previously, all 56 furnace wall soot blowers were operated once every 8 hours, consuming substantial steam. Through a study, JPL found that operating soot blowers in certain areas and sequences had little effect on boiler parameters. This allowed reducing operations to only blowing 14 blowers once daily and 28 blowers every other day, saving over 1,300 tons of steam annually. Financial savings from reduced steam and coal usage were estimated at over 4 lakh rupees annually. The optimized strategy improved boiler performance and heat rate while reducing emissions and maintenance costs.
This document discusses optimum flame theory (OFT), which seeks to establish scientific principles for optimizing flames in cement kilns. OFT is based on combustion aerodynamics and jet mixing laws. It provides guidelines known by the mnemonic "SADAM" to optimize flame size, alignment, dryness, air, and momentum. Properly applying these guidelines can improve output, reduce build-up issues, and improve clinker quality by ensuring complete fuel-air mixing before combustion. The document explains how burner momentum should be calculated based on thermal load, and how swirl can be effectively used to induce internal reverse flow and heat fuels if the swirl is sufficiently strong and contained by axial flow.
Exhibit 13 On ignition mechanisms of premixed CH4air and H2air using a hot ...Saad Tanvir
This research paper investigates the ignition mechanisms of premixed methane/air and hydrogen/air mixtures using a turbulent hot jet generated by pre-chamber combustion. Two ignition mechanisms were identified: jet ignition, where the jet contains only hot combustion products, and flame ignition, where the jet contains wrinkled turbulent flames and active radicals. Ignition behavior was studied under different operating parameters, and a Damköhler number was defined to characterize ignition probability independently of parameters. Jet ignition and flame ignition mostly occurred in the thin reaction zone regime, while non-ignition cases fell in the broken reaction zone regime.
DESIGN CRITERIA FOR OPTIMIZATION OF THE CROSS IGNITION PROCESS IN GASTURBINE-...ijscmcjournal
Reducing of pollutants with simultaneous increase of the gas turbine power, is always a fundamental aim
of the Turbine technology. New developed structures and operating systems in the turbine production have
been established. In the meanwhile, burning instabilities are still appearing in these systems during a
Cross-ignition process (CI), creating pollutants due to high flame temperatures, and are not yet completely
investigated.
The phenomena of a CI is taking place during operation of malty-burner combustion chambers, when one
burner is extinguished and a particular volume of combustible mixture is formed in the distance between
this burner and the adjacent lightened one, which considered to be as an ignition path.
Cross ignition process should be performed along the ignition path in a particularly controlled small time.
So that, no excessive quantities of combustible mixtures will be injected during this time in the combustion
chamber. Otherwise, burning instabilities and mechanical wear will be occurred.
Depending on this illustration, the Cross Ignition Time (CIT) of an extinguished burner, that will be
considered as the evaluation measure for the entire cross-ignition process, should be Possibly as low as its
normal ignition time.
The main objective of this project is to reproduce constructive criteria for controlling of cross ignition
process by influencing the mixing process and heat flux in a defined mixing zone existing along the ignition
path.
Design Criteria for Optimization of the Cross Ignition Process in Gasturbine-...ijscmcj
Reducing of pollutants with simultaneous increase of the gas turbine power, is always a fundamental aim of the Turbine technology. New developed structures and operating systems in the turbine production have been established. In the meanwhile, burning instabilities are still appearing in these systems during a Cross-ignition process (CI), creating pollutants due to high flame temperatures, and are not yet completely investigated.The phenomena of a CI is taking place during operation of malty-burner combustion chambers, when one burner is extinguished and a particular volume of combustible mixture is formed in the distance between this burner and the adjacent lightened one, which considered to be as an ignition path. Cross ignition process should be performed along the ignition path in a particularly controlled small time.So that, no excessive quantities of combustible mixtures will be injected during this time in the combustion chamber. Otherwise, burning instabilities and mechanical wear will be occurred. Depending on this illustration, the Cross Ignition Time (CIT) of an extinguished burner, that will be considered as the evaluation measure for the entire cross-ignition process, should be Possibly as low as its normal ignition time.The main objective of this project is to reproduce constructive criteria for controlling of cross ignition process by influencing the mixing process and heat flux in a defined mixing zone existing along the ignition path.
This document summarizes a CFD investigation of the effect of changing the angle of secondary air on NOx emissions in a 660 MW tangentially fired coal boiler. The study found that changing the angle of secondary air from horizontal to an inclined angle reduced NOx levels at the furnace outlet by 15%, from 166 ppm to 143 ppm. A CFD model was developed and validated against plant data to analyze the combustion and flow patterns with different secondary air parameters. The optimized secondary air configuration lowered NOx emissions through improved mixing and delayed ignition.
Expanded graphite as thermal conductivity enhancer for paraffin wax being us...Gulfam Raza
This document summarizes research on using expanded graphite (EG) as a thermal conductivity enhancer in paraffin wax for thermal energy storage applications. Three samples of paraffin/EG composite were prepared with 5%, 10%, and 15% EG by weight. Testing showed the thermal conductivity was increased 4, 6, and 6.5 times compared to pure paraffin wax. Differential scanning calorimetry showed the melting temperature was unchanged but latent heat was slightly lower. Microscopy indicated uniform mixing of paraffin and EG. The composite passed liquid leakage testing, confirming its form stability. The enhanced thermal conductivity and form stability demonstrate potential for using this composite in thermal energy storage systems.
Effect of rim geometry on burner stability Conference paper2019Jameel Tawfiq
A swirl burner with different length to rim diameter ratio L/D. A three ratios 1,2 and 3 were studied. The results show that a change in the L/D ratio will effect on the stabilization position of the flame in downstream. The equivalence ratio of the mixture was taken a constant for the comparison sake. The flame stabilizes closer to the rim with an increase of the rim length.
This document describes a computational fluid dynamics (CFD) model developed to analyze and counteract ring formation in rotary kilns used in cement production. The model revealed that rings typically form in zones of maximum radiative heat transfer, causing local overheating and overproduction of liquid material that sticks to the kiln wall. To counteract this, the model proposes increasing secondary air injection to cool the kiln and eliminate temperature peaks that cause ring formation. Experimental validation at the plant confirmed that increasing secondary air was effective at preventing unscheduled shutdowns from ring formation.
This document describes a computational fluid dynamics (CFD) model developed to address ring formation in rotary kilns used for cement production. The model revealed that rings typically form in zones of maximum radiative heat transfer, causing local overheating and increased liquid phase production of material. To counteract ring formation, the model proposes increasing secondary air injection to cool the kiln and eliminate temperature peaks. Experimental validation at the plant confirmed this solution effectively prevented unscheduled shutdowns from ring formation.
This document summarizes a study that performed a life assessment of a fighter jet engine annular combustor liner using a combined fluid/structural approach. Computational fluid dynamics analyses were conducted to obtain the thermal loading on the combustor liner from the combustion process. Finite element analyses were then performed to calculate the resulting temperature and stress/strain distributions in the liner. A method was developed to analyze a complete measured flight profile with limited computational effort. The creep and fatigue life for a measured flight were calculated and compared to field experience data. While the exact number of cycles to crack initiation was difficult to predict, the locations and directions of cracking correlated well with field data.
Simulation Studies Of Premixed N-Pentane/Air Liquid Micro CombustionIJERA Editor
With latest improvements in MEMS, combustion based Micro-Power generation devices are seen as alternatives for conventional batteries because of the high energy densities of Hydrogen and other hydrocarbon fuels. An important feature of micro-power system is to utilize the combustion of fuel or propellant in the micro-burner to produce the gas with high temperature and high pressure to drive turbines or other power units, which convert chemical into energy directly or indirectly other forms of energy, for example heat or power. We have concentrated on the usage of Micro combustion as a substitute for conventional batteries .In our study, a Micro Combustor of 1mm x 10mm is taken for Numerical Study. Combustion characteristics of N Pentane-Air mixture in a planar micro-channel is studied numerically. We have performed the liquid fuel combustion of n-Pentane and air to study the effects of liquid fuel combustion in a micro channel. The effect of axial velocity inlet, on exhaust gas temperature and Hydrogen Peroxide addition on exhaust gas concentration was analyzed respectively. We also investigated numerically the combustion characteristics under different conditions such as by varying the DPM, Number of Fuel Streams, and Spray Angle and so on. For this numerical analysis, an experimental model is considered as reference, and the geometry and the boundary conditions are taken from it for the purpose of simulation. In this study, n-Pentane is introduced as liquid droplets at the centerline and the liquid combustion is simulated numerically.
Wingwall sh distortion in cfbc boilers by k.k.parthiban jan 2018parthi2006
1) Distortion of wingwall superheaters in circulating fluidized bed combustion (CFBC) boilers can occur due to uneven thermal expansion during startup before protective ash beds form in the furnace.
2) The wingwall superheater expands more than expected during dry heating at startup before cooling steam is available, exceeding the range of typical constant load hangers.
3) This leads to buckling and permanent deformation of thin wingwall panels, which is then exacerbated by each subsequent startup. Replacement of damaged panels and use of hangers allowing larger expansion is needed to prevent recurrence.
MODELLING FOR CROSS IGNITION TIME OF A TURBULENT COLD MIXTURE IN A MULTI BURN...ijcsa
This document presents a computational model for determining the cross-ignition time of a turbulent cold mixture in a multi-burner combustor. The model accounts for various parameters that influence heat transfer during the cross-ignition process. Experimental validation was conducted using a simple test rig with two burners. Preliminary results from the experiments show relationships between cross-ignition time and factors like the flow area between burners, distance between burners, and flame properties. Computational fluid dynamics simulations will also be used to further investigate heat transfer in high-velocity regions and validate the model under more conditions.
The poster presentation is a part of my academic thesis. It is the pre-defense of my group about our thesis topic, "Performance Enhancement of Phase-Changing Material by Embedding Lower Fin".
Similar to Final report for development of enclosed combustion rig for scramjet fuel studies (20)
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
TIME DIVISION MULTIPLEXING TECHNIQUE FOR COMMUNICATION SYSTEMHODECEDSIET
Time Division Multiplexing (TDM) is a method of transmitting multiple signals over a single communication channel by dividing the signal into many segments, each having a very short duration of time. These time slots are then allocated to different data streams, allowing multiple signals to share the same transmission medium efficiently. TDM is widely used in telecommunications and data communication systems.
### How TDM Works
1. **Time Slots Allocation**: The core principle of TDM is to assign distinct time slots to each signal. During each time slot, the respective signal is transmitted, and then the process repeats cyclically. For example, if there are four signals to be transmitted, the TDM cycle will divide time into four slots, each assigned to one signal.
2. **Synchronization**: Synchronization is crucial in TDM systems to ensure that the signals are correctly aligned with their respective time slots. Both the transmitter and receiver must be synchronized to avoid any overlap or loss of data. This synchronization is typically maintained by a clock signal that ensures time slots are accurately aligned.
3. **Frame Structure**: TDM data is organized into frames, where each frame consists of a set of time slots. Each frame is repeated at regular intervals, ensuring continuous transmission of data streams. The frame structure helps in managing the data streams and maintaining the synchronization between the transmitter and receiver.
4. **Multiplexer and Demultiplexer**: At the transmitting end, a multiplexer combines multiple input signals into a single composite signal by assigning each signal to a specific time slot. At the receiving end, a demultiplexer separates the composite signal back into individual signals based on their respective time slots.
### Types of TDM
1. **Synchronous TDM**: In synchronous TDM, time slots are pre-assigned to each signal, regardless of whether the signal has data to transmit or not. This can lead to inefficiencies if some time slots remain empty due to the absence of data.
2. **Asynchronous TDM (or Statistical TDM)**: Asynchronous TDM addresses the inefficiencies of synchronous TDM by allocating time slots dynamically based on the presence of data. Time slots are assigned only when there is data to transmit, which optimizes the use of the communication channel.
### Applications of TDM
- **Telecommunications**: TDM is extensively used in telecommunication systems, such as in T1 and E1 lines, where multiple telephone calls are transmitted over a single line by assigning each call to a specific time slot.
- **Digital Audio and Video Broadcasting**: TDM is used in broadcasting systems to transmit multiple audio or video streams over a single channel, ensuring efficient use of bandwidth.
- **Computer Networks**: TDM is used in network protocols and systems to manage the transmission of data from multiple sources over a single network medium.
### Advantages of TDM
- **Efficient Use of Bandwidth**: TDM all
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.