1. The document discusses internal combustion engines and the formation of gaseous pollutants and photochemical smog.
2. It describes how tuning factors like air-fuel ratio, compression, timing, and exhaust gas recycling can impact emissions of pollutants like carbon monoxide, hydrocarbons, and nitrogen oxides from automobile engines.
3. The formation of nitrogen oxides is explained through the Zeldovich mechanism and equations are provided for the rate of nitric oxide formation over time as exhaust gases cool.
- Automobiles are a major source of air pollutants like CO, NMHC, NOx, and Pb in developing countries.
- Four-stroke engines generate CO, NOx, and some HC from the exhaust. Two-stroke engines generate aerosols, CO, VOCs but little NOx. Diesel engines produce NOx and soot but little CO.
- The formation of NOx from internal combustion engines is controlled by kinetics, not equilibrium. High exhaust temperatures favor NOx formation, while cooling "freezes" the NOx levels.
This document provides an overview of engine emissions and emission standards. It discusses the types of emissions from internal combustion engines, including hydrocarbons, carbon monoxide, and oxides of nitrogen. It also compares Indian Bharat emission standards to European Euro norms, noting differences in testing temperatures and maximum tested speeds. The document outlines the causes of different emissions and how emission standards aim to regulate the amounts of pollutants released.
1. Pollutants like hydrocarbons, carbon monoxide, oxides of nitrogen, and particulates form in internal combustion engines due to incomplete combustion and high combustion temperatures. The amount of each pollutant depends on factors like air-fuel ratio, combustion chamber design, and operating conditions.
2. Hydrocarbons form due to flame quenching, fuel trapped in crevices and deposits, and misfires. Carbon monoxide occurs under fuel-rich conditions when there is not enough oxygen for full combustion of the carbon. Oxides of nitrogen form through high temperature reactions between nitrogen and oxygen in the air. Particulates include soot and condensed hydrocarbons.
3. Pollutants are measured using
The document discusses various technologies used to reduce vehicle emissions, including exhaust gas recirculation (EGR), catalytic converters, air injection, fuel evaporative emission control, hybrid vehicles, and alternate fuels. EGR works by recirculating a portion of exhaust gases back into the engine cylinders to reduce combustion temperatures and nitrogen oxide emissions. Catalytic converters use catalyzed chemical reactions to convert toxic pollutants like carbon monoxide, unburned hydrocarbons, and nitrogen oxides in exhaust into less toxic substances. Other technologies aim to control evaporative emissions from the fuel system and reduce emissions through the use of hybrid powertrains or alternative low-emission fuels.
This document discusses emissions and emission control strategies in internal combustion engines. It covers the formation of various emissions like carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons, and particulates in both spark ignition (SI) and compression ignition (CI) engines. It also discusses emission control methods like catalytic converters and exhaust gas recirculation (EGR). The key points are: emissions form due to incomplete combustion and high temperatures; a three-way catalytic converter controls CO, HC, and NOx using platinum, palladium and rhodium; and EGR reduces NOx by lowering combustion temperatures but increases particulates.
The document discusses various sources of emissions from internal combustion engines and emission control strategies. It covers the primary emissions from gasoline and diesel engines like CO, HC, NOx, and PM. It also outlines emission norms for different vehicle types over different periods in countries like India. Furthermore, it analyzes the formation of different emissions like hydrocarbons, carbon monoxide, nitrogen oxides, and particulates in detail. Lastly, it discusses approaches to control emissions like improving combustion, optimizing operating parameters, and using after-treatment devices like catalytic converters.
- Automobiles are a major source of air pollutants like CO, NMHC, NOx, and Pb in developing countries.
- Four-stroke engines generate CO, NOx, and some HC from the exhaust. Two-stroke engines generate aerosols, CO, VOCs but little NOx. Diesel engines produce NOx and soot but little CO.
- The formation of NOx from internal combustion engines is controlled by kinetics, not equilibrium. High exhaust temperatures favor NOx formation, while cooling "freezes" the NOx levels.
This document provides an overview of engine emissions and emission standards. It discusses the types of emissions from internal combustion engines, including hydrocarbons, carbon monoxide, and oxides of nitrogen. It also compares Indian Bharat emission standards to European Euro norms, noting differences in testing temperatures and maximum tested speeds. The document outlines the causes of different emissions and how emission standards aim to regulate the amounts of pollutants released.
1. Pollutants like hydrocarbons, carbon monoxide, oxides of nitrogen, and particulates form in internal combustion engines due to incomplete combustion and high combustion temperatures. The amount of each pollutant depends on factors like air-fuel ratio, combustion chamber design, and operating conditions.
2. Hydrocarbons form due to flame quenching, fuel trapped in crevices and deposits, and misfires. Carbon monoxide occurs under fuel-rich conditions when there is not enough oxygen for full combustion of the carbon. Oxides of nitrogen form through high temperature reactions between nitrogen and oxygen in the air. Particulates include soot and condensed hydrocarbons.
3. Pollutants are measured using
The document discusses various technologies used to reduce vehicle emissions, including exhaust gas recirculation (EGR), catalytic converters, air injection, fuel evaporative emission control, hybrid vehicles, and alternate fuels. EGR works by recirculating a portion of exhaust gases back into the engine cylinders to reduce combustion temperatures and nitrogen oxide emissions. Catalytic converters use catalyzed chemical reactions to convert toxic pollutants like carbon monoxide, unburned hydrocarbons, and nitrogen oxides in exhaust into less toxic substances. Other technologies aim to control evaporative emissions from the fuel system and reduce emissions through the use of hybrid powertrains or alternative low-emission fuels.
This document discusses emissions and emission control strategies in internal combustion engines. It covers the formation of various emissions like carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons, and particulates in both spark ignition (SI) and compression ignition (CI) engines. It also discusses emission control methods like catalytic converters and exhaust gas recirculation (EGR). The key points are: emissions form due to incomplete combustion and high temperatures; a three-way catalytic converter controls CO, HC, and NOx using platinum, palladium and rhodium; and EGR reduces NOx by lowering combustion temperatures but increases particulates.
The document discusses various sources of emissions from internal combustion engines and emission control strategies. It covers the primary emissions from gasoline and diesel engines like CO, HC, NOx, and PM. It also outlines emission norms for different vehicle types over different periods in countries like India. Furthermore, it analyzes the formation of different emissions like hydrocarbons, carbon monoxide, nitrogen oxides, and particulates in detail. Lastly, it discusses approaches to control emissions like improving combustion, optimizing operating parameters, and using after-treatment devices like catalytic converters.
Pollutant,their formation and control in Internal Combustion EnginesHassan Raza
The document discusses pollutant formation and control in internal combustion engines. It introduces the main pollutants from spark ignition and diesel engines as nitrogen oxides, carbon monoxide, and unburned or partially burned hydrocarbons. It then explains the formation of nitrogen oxides and emissions in diesel engines, including unburned hydrocarbons and particulate emissions. Finally, it discusses methods to control engine emissions, including engineering combustion processes, optimizing operating parameters, and using after-treatment devices like catalytic converters.
The document discusses air pollution from internal combustion engines and methods to control pollutant formation. It defines key terms like air pollution, emissions, and criteria pollutants. It then describes the major pollutants like particulate matter, carbon monoxide, nitrogen oxides, and hydrocarbons that are emitted from gasoline and diesel engines. The document outlines various solutions that can be used to reduce emissions, such as improving engine design, using cleaner fuels, installing emission control devices, and promoting practices like proper vehicle maintenance and more efficient driving. Measurement techniques for analyzing pollutants are also summarized.
This document presents information on engine emissions and control methods. It discusses the different types of exhaust emissions from engines, including unburnt hydrocarbons, oxides of carbon, nitrogen, and particulates. It also examines non-exhaust emissions and the factors that influence emissions levels. Emission control methods covered include thermal converters and catalytic converters, which use platinum, palladium and rhodium to convert harmful exhaust gases into less harmful emissions. Problems with catalytic converters like cold starts and non-exhaust emissions are also outlined.
Emission control technologies for automobilesShiril Saju
- The document discusses various emission control technologies used in automobiles to reduce air pollutants from vehicle exhaust. It outlines technologies like electronic fuel injection systems, multi-point fuel injection, direct injection systems, and catalytic converters.
- Key pollutants of concern from vehicles include hydrocarbons, carbon monoxide, nitrogen oxides, particulate matter, and sulfur oxides. Emission standards called Bharat Stage standards are instituted in India based on European EURO standards to regulate these pollutants.
- The technologies discussed aim to more efficiently and completely combust fuel to reduce emissions through things like precise fuel metering and computerized engine management. Catalytic converters also help to break down remaining pollutants in
Literature review of diesel includes...Hydocarbon introduction, Hydrocarbon properties, Diesel production techniques & routes, Selection of best techique for diesel production, Technology provider & licencers.
The document discusses positive crankcase ventilation systems which draw crankcase vapors into the engine's intake manifold to be burned. It describes how PCV valves control the flow of crankcase gases and air into the engine.
Selective Catalytic Reduction (SCR) is an advanced active emissions control technology system that injects a liquid-reductant agent through a special catalyst into the exhaust stream of a diesel engine. The reductant source is usually automotive-grade urea, otherwise known as Diesel Exhaust Fluid (DEF). The DEF sets off a chemical reaction that converts nitrogen oxides into nitrogen, water and tiny amounts of carbon dioxide (CO2), natural components of the air we breathe, which is then expelled through the vehicle tailpipe.
SCR technology is designed to permit nitrogen oxide (NOx) reduction reactions to take place in an oxidizing atmosphere. It is called "selective" because it reduces levels of NOx using ammonia as a reductant within a catalyst system. The chemical reaction is known as "reduction" where the DEF is the reducing agent that reacts with NOx to convert the pollutants into nitrogen, water and tiny amounts of CO2. The DEF can be rapidly broken down to produce the oxidizing ammonia in the exhaust stream. SCR technology alone can achieve NOx reductions up to 90 percent
Crude oil is separated into fractions by fractional distillation based on differences in boiling points. The fractions include refinery gas, light gasoline, naphtha, kerosene, gas oil, and residue. These fractions are used to produce fuels like petrol, diesel, and jet fuel. Petrol is a complex mixture of hydrocarbons, mainly alkanes and aromatics. Its octane rating, which indicates its resistance to premature ignition, can be increased through processes like isomerization, dehydrocyclization, and catalytic cracking that produce more branched and cyclic molecules.
Petroleum products are essential resources extracted through fractional distillation of crude oil. They serve as fuels and feedstocks. As fuels, hydrocarbons like petrol and diesel combust to release energy, powering engines. As feedstocks, petrochemicals are used to produce plastics, solvents, lubricants, and other materials. Petroleum products have diverse applications beyond fuel due to their chemical properties. Their widespread use is due to being stable, versatile resources that provide cheap energy and materials critical to modern life.
The document discusses petroleum refining, cracking, and methods of producing synthetic petrol. It describes how crude oil is refined through separation, conversion, and treatment processes like distillation. Cracking breaks large hydrocarbon molecules into smaller, more useful molecules through thermal or catalytic cracking. Synthetic petrol can be produced via polymerization, Fischer-Tropsch synthesis from syngas, or Bergius process where coal is hydrogenated over a catalyst into liquid fuels.
This document summarizes the process of steel manufacturing in New Zealand. Iron ore is first reduced to iron in rotary kilns, producing a substance called reduced primary concentrate and char. This is then melted into molten iron in electric melters. The molten iron undergoes vanadium recovery and is then converted to steel in a Klockner Oxygen Blown Maxhutte furnace. Oxygen is blown through the furnace to oxidize impurities, which are separated as slag. Alloying elements are then added to produce the final steel product.
fractional distillation and refining of petroleumAfzal Zubair
Petroleum is a complex mixture of hydrocarbons and other compounds that varies in composition depending on its source. It is a thick, brown liquid found below the earth's surface. Refining petroleum involves separating it into fractions of different boiling points and removing impurities through fractional distillation. In fractional distillation, the mixture is heated and different compounds condense out of the vapor at different levels in the distillation tower based on their boiling points. Over 500 compounds can be obtained through petroleum distillation.
Petroleum is refined into many important products through fractional distillation. These petroleum products, also called petrochemicals, are used as fuels like gasoline, diesel and kerosene. However, petrochemicals also serve as feedstocks for many other materials like plastics, solvents, lubricants, and pharmaceuticals. The petroleum industry produces fuels and materials that are essential to modern life.
This document discusses different types of emissions from engines, including exhaust and non-exhaust emissions. It describes the key pollutants like unburnt hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), particulate matter, and sulfur dioxide. The document explains the factors that influence emissions formation in spark ignition and compression ignition engines, such as fuel-air mixture, combustion temperature, and engine operating conditions. It also discusses the limitations of hydrocarbons and the processes that lead to HC and CO emissions from spark ignition engines.
Description of the Exhaust system along with its components such as Exhaust manifold,catalytic converter ,muffler ,exhaust tubing and oxygen sensor.The working of some of these components is also explained.
Engine Emissions at Various Cetane Numbers with Exhaust Gas RecirculationIOSR Journals
Typical engine fuels are blends of various fuels species, i.e., multi component. Thus, the original
single component fuel vaporization model was replaced by a multi component fuel vaporization model .The
model has been extended to model diesel sprays under typical diesel conditions, including the effect of fuel
cetane number variation .Necessary modifications were carried out at the various cooling rates. Found the
performance of the diesel engine under various cooling rates at various cetane numbers, also various quantities
of exhaust gas was re circulated and found performance of the engine
Electrochemical synthetic hydrocarbons - Rambach - for printing with title pageGlenn Rambach
The document describes using solid oxide electrochemistry to produce synthetic hydrocarbon fuels from water and carbon dioxide. It discusses using solid oxide electrolysis cells to electrolyze water and carbon dioxide into hydrogen, carbon monoxide, and oxygen. The gases can then undergo further electrochemical and catalytic reactions to produce synthetic fuels like diesel. Configurations are proposed involving porous electrodes, solid electrolytes, and downstream catalysts to facilitate these reactions in a single system. Thermochemical and electrochemical processes are compared for producing hydrogen and synthesis gas as intermediates for fuel synthesis.
- The document discusses exhaust gas recirculation (EGR) systems, which aim to reduce nitrogen oxide (NOx) emissions from diesel engines. EGR works by recirculating a portion of exhaust gas back into the engine cylinders.
- EGR reduces NOx formation by increasing ignition delay, heat capacity, and diluting the combustion mixture. It has been shown to help engines meet strict EPA emissions requirements.
- EGR systems can be classified based on operating conditions, temperature, and pressure. The document focuses on how EGR lowers NOx by changing combustion chamber temperatures and chemistry.
This document summarizes reactions and applications of methanol. It describes reactions involving cleavage of the O-H bond including reactions with active metals and acids, and oxidation reactions. It also describes reactions involving cleavage of the C-O bond including reactions with hydrochloric acid and phosphorus compounds. Applications discussed include use as a fuel in vehicles and for producing biodiesel, as a solvent, in waste water treatment, as an intermediate in chemical synthesis, and in direct methanol fuel cells, camping stoves, and formerly as an antifreeze.
Tillman Hatcher's experience with internal combustion engine design includes over 150 topics related to engine components, operation cycles, performance characteristics, emissions, heat transfer, friction, lubrication, modeling, and more. His expertise spans spark-ignition engines, compression-ignition engines, and alternative engine technologies.
The document provides an overview of internal combustion engines. It discusses the basic classifications and cycles of internal combustion engines including two-stroke and four-stroke engines. It also covers the workings of spark ignition and compression ignition engines, as well as common engine components and systems such as carburetors and fuel injection systems. Key topics include the Otto, Diesel, and Carnot power cycles; combustion stages; valve timing diagrams; and scavenging, pre-ignition, detonation, lubrication, and emissions control.
Pollutant,their formation and control in Internal Combustion EnginesHassan Raza
The document discusses pollutant formation and control in internal combustion engines. It introduces the main pollutants from spark ignition and diesel engines as nitrogen oxides, carbon monoxide, and unburned or partially burned hydrocarbons. It then explains the formation of nitrogen oxides and emissions in diesel engines, including unburned hydrocarbons and particulate emissions. Finally, it discusses methods to control engine emissions, including engineering combustion processes, optimizing operating parameters, and using after-treatment devices like catalytic converters.
The document discusses air pollution from internal combustion engines and methods to control pollutant formation. It defines key terms like air pollution, emissions, and criteria pollutants. It then describes the major pollutants like particulate matter, carbon monoxide, nitrogen oxides, and hydrocarbons that are emitted from gasoline and diesel engines. The document outlines various solutions that can be used to reduce emissions, such as improving engine design, using cleaner fuels, installing emission control devices, and promoting practices like proper vehicle maintenance and more efficient driving. Measurement techniques for analyzing pollutants are also summarized.
This document presents information on engine emissions and control methods. It discusses the different types of exhaust emissions from engines, including unburnt hydrocarbons, oxides of carbon, nitrogen, and particulates. It also examines non-exhaust emissions and the factors that influence emissions levels. Emission control methods covered include thermal converters and catalytic converters, which use platinum, palladium and rhodium to convert harmful exhaust gases into less harmful emissions. Problems with catalytic converters like cold starts and non-exhaust emissions are also outlined.
Emission control technologies for automobilesShiril Saju
- The document discusses various emission control technologies used in automobiles to reduce air pollutants from vehicle exhaust. It outlines technologies like electronic fuel injection systems, multi-point fuel injection, direct injection systems, and catalytic converters.
- Key pollutants of concern from vehicles include hydrocarbons, carbon monoxide, nitrogen oxides, particulate matter, and sulfur oxides. Emission standards called Bharat Stage standards are instituted in India based on European EURO standards to regulate these pollutants.
- The technologies discussed aim to more efficiently and completely combust fuel to reduce emissions through things like precise fuel metering and computerized engine management. Catalytic converters also help to break down remaining pollutants in
Literature review of diesel includes...Hydocarbon introduction, Hydrocarbon properties, Diesel production techniques & routes, Selection of best techique for diesel production, Technology provider & licencers.
The document discusses positive crankcase ventilation systems which draw crankcase vapors into the engine's intake manifold to be burned. It describes how PCV valves control the flow of crankcase gases and air into the engine.
Selective Catalytic Reduction (SCR) is an advanced active emissions control technology system that injects a liquid-reductant agent through a special catalyst into the exhaust stream of a diesel engine. The reductant source is usually automotive-grade urea, otherwise known as Diesel Exhaust Fluid (DEF). The DEF sets off a chemical reaction that converts nitrogen oxides into nitrogen, water and tiny amounts of carbon dioxide (CO2), natural components of the air we breathe, which is then expelled through the vehicle tailpipe.
SCR technology is designed to permit nitrogen oxide (NOx) reduction reactions to take place in an oxidizing atmosphere. It is called "selective" because it reduces levels of NOx using ammonia as a reductant within a catalyst system. The chemical reaction is known as "reduction" where the DEF is the reducing agent that reacts with NOx to convert the pollutants into nitrogen, water and tiny amounts of CO2. The DEF can be rapidly broken down to produce the oxidizing ammonia in the exhaust stream. SCR technology alone can achieve NOx reductions up to 90 percent
Crude oil is separated into fractions by fractional distillation based on differences in boiling points. The fractions include refinery gas, light gasoline, naphtha, kerosene, gas oil, and residue. These fractions are used to produce fuels like petrol, diesel, and jet fuel. Petrol is a complex mixture of hydrocarbons, mainly alkanes and aromatics. Its octane rating, which indicates its resistance to premature ignition, can be increased through processes like isomerization, dehydrocyclization, and catalytic cracking that produce more branched and cyclic molecules.
Petroleum products are essential resources extracted through fractional distillation of crude oil. They serve as fuels and feedstocks. As fuels, hydrocarbons like petrol and diesel combust to release energy, powering engines. As feedstocks, petrochemicals are used to produce plastics, solvents, lubricants, and other materials. Petroleum products have diverse applications beyond fuel due to their chemical properties. Their widespread use is due to being stable, versatile resources that provide cheap energy and materials critical to modern life.
The document discusses petroleum refining, cracking, and methods of producing synthetic petrol. It describes how crude oil is refined through separation, conversion, and treatment processes like distillation. Cracking breaks large hydrocarbon molecules into smaller, more useful molecules through thermal or catalytic cracking. Synthetic petrol can be produced via polymerization, Fischer-Tropsch synthesis from syngas, or Bergius process where coal is hydrogenated over a catalyst into liquid fuels.
This document summarizes the process of steel manufacturing in New Zealand. Iron ore is first reduced to iron in rotary kilns, producing a substance called reduced primary concentrate and char. This is then melted into molten iron in electric melters. The molten iron undergoes vanadium recovery and is then converted to steel in a Klockner Oxygen Blown Maxhutte furnace. Oxygen is blown through the furnace to oxidize impurities, which are separated as slag. Alloying elements are then added to produce the final steel product.
fractional distillation and refining of petroleumAfzal Zubair
Petroleum is a complex mixture of hydrocarbons and other compounds that varies in composition depending on its source. It is a thick, brown liquid found below the earth's surface. Refining petroleum involves separating it into fractions of different boiling points and removing impurities through fractional distillation. In fractional distillation, the mixture is heated and different compounds condense out of the vapor at different levels in the distillation tower based on their boiling points. Over 500 compounds can be obtained through petroleum distillation.
Petroleum is refined into many important products through fractional distillation. These petroleum products, also called petrochemicals, are used as fuels like gasoline, diesel and kerosene. However, petrochemicals also serve as feedstocks for many other materials like plastics, solvents, lubricants, and pharmaceuticals. The petroleum industry produces fuels and materials that are essential to modern life.
This document discusses different types of emissions from engines, including exhaust and non-exhaust emissions. It describes the key pollutants like unburnt hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), particulate matter, and sulfur dioxide. The document explains the factors that influence emissions formation in spark ignition and compression ignition engines, such as fuel-air mixture, combustion temperature, and engine operating conditions. It also discusses the limitations of hydrocarbons and the processes that lead to HC and CO emissions from spark ignition engines.
Description of the Exhaust system along with its components such as Exhaust manifold,catalytic converter ,muffler ,exhaust tubing and oxygen sensor.The working of some of these components is also explained.
Engine Emissions at Various Cetane Numbers with Exhaust Gas RecirculationIOSR Journals
Typical engine fuels are blends of various fuels species, i.e., multi component. Thus, the original
single component fuel vaporization model was replaced by a multi component fuel vaporization model .The
model has been extended to model diesel sprays under typical diesel conditions, including the effect of fuel
cetane number variation .Necessary modifications were carried out at the various cooling rates. Found the
performance of the diesel engine under various cooling rates at various cetane numbers, also various quantities
of exhaust gas was re circulated and found performance of the engine
Electrochemical synthetic hydrocarbons - Rambach - for printing with title pageGlenn Rambach
The document describes using solid oxide electrochemistry to produce synthetic hydrocarbon fuels from water and carbon dioxide. It discusses using solid oxide electrolysis cells to electrolyze water and carbon dioxide into hydrogen, carbon monoxide, and oxygen. The gases can then undergo further electrochemical and catalytic reactions to produce synthetic fuels like diesel. Configurations are proposed involving porous electrodes, solid electrolytes, and downstream catalysts to facilitate these reactions in a single system. Thermochemical and electrochemical processes are compared for producing hydrogen and synthesis gas as intermediates for fuel synthesis.
- The document discusses exhaust gas recirculation (EGR) systems, which aim to reduce nitrogen oxide (NOx) emissions from diesel engines. EGR works by recirculating a portion of exhaust gas back into the engine cylinders.
- EGR reduces NOx formation by increasing ignition delay, heat capacity, and diluting the combustion mixture. It has been shown to help engines meet strict EPA emissions requirements.
- EGR systems can be classified based on operating conditions, temperature, and pressure. The document focuses on how EGR lowers NOx by changing combustion chamber temperatures and chemistry.
This document summarizes reactions and applications of methanol. It describes reactions involving cleavage of the O-H bond including reactions with active metals and acids, and oxidation reactions. It also describes reactions involving cleavage of the C-O bond including reactions with hydrochloric acid and phosphorus compounds. Applications discussed include use as a fuel in vehicles and for producing biodiesel, as a solvent, in waste water treatment, as an intermediate in chemical synthesis, and in direct methanol fuel cells, camping stoves, and formerly as an antifreeze.
Tillman Hatcher's experience with internal combustion engine design includes over 150 topics related to engine components, operation cycles, performance characteristics, emissions, heat transfer, friction, lubrication, modeling, and more. His expertise spans spark-ignition engines, compression-ignition engines, and alternative engine technologies.
The document provides an overview of internal combustion engines. It discusses the basic classifications and cycles of internal combustion engines including two-stroke and four-stroke engines. It also covers the workings of spark ignition and compression ignition engines, as well as common engine components and systems such as carburetors and fuel injection systems. Key topics include the Otto, Diesel, and Carnot power cycles; combustion stages; valve timing diagrams; and scavenging, pre-ignition, detonation, lubrication, and emissions control.
This document outlines the syllabus for an advanced internal combustion engines course. The course is divided into 5 units that cover topics such as: carburetion and combustion in spark ignition engines; compression ignition engines; engine exhaust emission control; alternate fuels; and recent engine technologies. Unit 1 discusses the air-fuel ratio requirements for spark ignition engines, carburetor design and operation, combustion stages, knock factors, and thermodynamic analysis of the combustion process.
Analisa Sistem Pembuangan pada Mobil yang menggunakan turbocharger dengan mob...Alen Pepa
Sistem pembuangan pada mobil berfungsi untuk mengalirkan gas buang hasil pembakaran mesin ke luar dengan aman. Sistem ini terdiri dari pipa pembuangan, catalytic converter, knalpot, dan peredam suara. Perbedaan antara mobil biasa dan mobil balap terletak pada penggunaan turbocharger pada mobil balap untuk meningkatkan kinerja mesin."
Draft Artikel Jurnal Internasional Financial Literacy Development for Increas...iosrjce
The purposes of this research are (1) identifying factor, actor that influences the character
learning for elementary school (2) identifying the influence factors for student in manage their money; (3)
finding the effective financial literacy learning models; (4) measuring financial literacy learning models
effectivity to create entrepreneurship and non consumerist character; (5) Formulate the effective financial
literacy learning models. ( Hanya sampai no 3, ini kan penelitian sampai no 3 saja)
Using the R & D methods this research conducting in 2 years. The first years to find out the purpose 1 up to 3,
the second years to find out the effectively of the models. The research object at Elementary School in
Kabupaten Kudus (Kudus Municipality). Model pembelajaran finacial literacy terdiri infut, proses, out put
Sistem kontrol elektronik menggunakan sensor untuk mendeteksi kondisi mesin dan memberikan masukan kepada ECU. ECU kemudian menghitung dan mengatur keluaran seperti waktu injeksi bahan bakar berdasarkan program dan data dari sensor untuk menjaga kinerja mesin. Sensor utama termasuk AFM, TPS, MAP, WTS, dan O2 sensor.
The document discusses different types of superchargers used to increase the power output of internal combustion engines. It describes supercharging as increasing the inlet air density to provide more air to the engine. There are three main types discussed: centrifugal superchargers which are mechanically driven; roots superchargers which use lobes to force air into the intake; and vane superchargers which use spring-loaded vanes. The document also covers four arrangements for driving superchargers: gear-driven from the engine; with an exhaust turbine; coupled engine and turbine; and gear-driven with a free turbine.
This document contains formulas related to internal combustion engines. It defines formulas for calculating the indicated power of four-stroke and two-stroke engines, brake power, friction power, mechanical efficiency, indicated thermal efficiency, brake thermal efficiency, relative efficiency, air standard efficiency, volumetric efficiency, specific output, and specific fuel consumption. The formulas are presented along with their variables and units of measurement. The document was prepared by students for a class on combustion engines.
This document discusses risk management. It defines risk management as identifying, monitoring, and limiting risks. Risks can come from accidents, natural causes, or deliberate attacks. Risk management is important in business to manage uncertainty and ensure compliance with policies. It is also important in the public sector to identify and mitigate risks to critical infrastructure. The document outlines traditional risk management programs and strategies like risk transfer, avoidance, reduction, and acceptance. It discusses establishing context, risk identification, assessment, potential treatments, creating risk management plans, and why plans need to be upgraded over time.
This document discusses various aspects of safety engineering including:
1. Safety engineering assures that life-critical systems function properly even when some components fail through techniques like failure mode and effects analysis.
2. System safety and reliability engineering analyzes complex safety-critical systems using methods like root cause analysis, visual inspections, and chemical/x-ray analysis.
3. Important safety measures include implementing standard protocols, training, instruction manuals, government regulations, and evaluating activities through specialists.
The document provides information on different types of internal combustion engines. It describes two-stroke and four-stroke engines, whether spark ignition or compression ignition. For both two-stroke and four-stroke engines, it explains the basic workings of each stroke in the combustion cycle, including intake, compression, power/expansion, and exhaust strokes. Diagrams and animations are included to illustrate the piston movement and valve timing in two-stroke and four-stroke engines.
The document discusses engine geometry and piston motion. It defines key terms like cylinder clearance volume, swept volume, compression ratio, and average and instantaneous piston speeds. It then covers topics like engine torque, power, indicated work, mechanical efficiency, power and torque curves, fuel consumption, combustion efficiency, and volumetric efficiency. Key parameters discussed include mean effective pressure, specific fuel consumption, thermal efficiency, and air-fuel ratio.
The document discusses key performance parameters of engines including thermal efficiencies, power outputs, specific fuel consumption, air-fuel ratios, and volumetric efficiency. It defines indicated thermal efficiency as the ratio of indicated power to fuel energy, and brake thermal efficiency as the ratio of brake power to fuel energy. Mechanical efficiency is the ratio of brake power to indicated power. Volumetric efficiency is the ratio of actual to theoretical air intake. Mean effective pressures and specific power input are also discussed.
This document discusses various criteria and comparisons of internal combustion engines, including:
1) Indicator power, brake power, friction power, thermal efficiency, specific fuel consumption, indicator mean effective pressure, torque, and volumetric efficiency are analyzed.
2) Graphs show relationships between torque and speed, brake power and indicated power vs speed, and mechanical efficiency vs speed and brake power.
3) Fuel consumption varies with engine speed, with laws enacted to require better vehicle fuel efficiency and decrease air pollution from depletion of fossil fuels.
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.
The document discusses different types of power steering systems used in vehicles. It describes hydraulic power steering systems which use a belt-driven pump to provide hydraulic pressure to assist steering. Electro-hydraulic systems use an electric motor instead of a belt to power the hydraulic pump. Electric power steering systems have sensors and a computer module that apply electric motor assist directly to the steering gear or column without hydraulics. The document also discusses Honda's electric power steering system used in the NSX which has precise control from an electric motor around the steering rack.
1) Automobiles are a major source of air pollutants like CO, hydrocarbons, NOx, and lead.
2) The formation of pollutants depends on factors like the air-fuel ratio, compression, and spark timing in internal combustion engines.
3) Leaner fuel mixtures and higher compression reduce CO but increase NOx, while retarded spark timing lowers maximum combustion temperatures to reduce both CO and NOx.
637InternalComb (1).ppt about engine of vehicleRamdhaniD
Automobiles are a major source of air pollutants like CO, NMHC, NOx, and Pb in developing countries. Their exhaust is the primary cause of photochemical smog. Internal combustion engines produce pollutants through incomplete combustion in the quench zone and as temperatures decrease in the exhaust. Nitric oxide (NO) forms through the Zeldovich mechanism and its concentration is controlled by reaction kinetics, favoring higher temperatures. Diesel engines generate more NOx and soot than gasoline engines due to their hotter, leaner combustion.
The document discusses various aspects of emissions and emission control in internal combustion engines. It covers the formation of CO, hydrocarbons, NOx and particulates in both diesel and gasoline engines. It also discusses various emission control techniques like catalytic converters, exhaust gas recirculation and particulate traps that are used to control engine-out emissions and help meet emission regulations. The highest level of control is achieved through precise fuel injection and ignition timing along with feedback from oxygen sensors in closed-loop three-way catalytic converter systems.
- Formation of CO and NOx in IC engines occurs due to locally rich fuel-air mixtures and high combustion temperatures, respectively. CO is also produced during engine warm up when running rich.
- Emissions from diesel engines include particulate matter from fuel that is overmixed or undermixed with air. Soot forms when the carbon to oxygen ratio exceeds a critical value.
- Emission control methods include improving combustion, optimizing operating parameters like spark timing, and using aftertreatment devices. Catalytic converters use precious metals to catalyze the conversion of CO, HC, and NOx to less harmful emissions through oxidation and reduction reactions.
Exhaust analysis of four stroke single cylinder diesel engine using copper ba...ijsrd.com
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2. IV. GASEOUS POLLUTION AND
PHOTOCHEMICAL SMOG
b. Formation
I. The Automobile Internal Combustion (Otto cycle)
Seinfeld Chapt. 3
Wark and Warner Chapt. 10
Main cause of L.A. type smog
Main source of CO, NMHC, NOx, and Pb in developing countries.
Mobile sources much stronger source than stationary sources for all
but NOx.
3. Image
INTAKE - Downward motion draws in air/fuel
mixture
COMPRESSION - For higher efficiency
POWER - Combustion initiated by spark plug
EXHAUST - Push out burned hydrocarbons
11. Exhaust is not the only source of air pollutants. In an unregulated auto:
Image
Gas tank 10%
Carburetor 10%
Crankcase* 25%
Exhaust 55%
Total 100%
Hydrocarbon Sources in an Unregulated Auto
* Called "Blowby"
12. Evaporation from gas tank and carburetor are easy to control, but essentially all
of the NOx, CO, and Pb comes from the exhaust.
Image
Recirculation System
• Engine off - vapors onto charcoal
• Engine on - intake sucks air and HC out of charcoal
• Positive crankcase ventilation
• Without controls 3% of the fuel would be lost
13. II. How to Tune a Car
Equilibrium calculation told us to burn lean and at high compression to produce
less CO. High compression also ups thermodynamic efficiency; Carnot cycle
efficiency is defined from the ratio of cold to hot temperatures:
A. Air-Fuel-Ratio
Best power at AFR of 12.5 (rich)
Best mileage at 15.5 (lean)
ARF above 17 causes misfiring
ARF below 10 causes flooding and plug fouling
ARF of about 14.5 (Φ = 1.0) is stoichiometric
14. •Automobiles: Otto cycle the cycle used in spark-ignition internal
combustion engines run on gasoline. Its theoretical efficiency depends on
the compression ratio r of the engine and the specific heat ratio (Cp/Cv = γ)
of the gas in the combustion chamber.
The higher the compression ratio, the higher the temperature in the
cylinder as the fuel burns and so the higher the efficiency. The
maximum compression ratio usable is limited by the need to prevent
preignition (knocking), where the fuel ignites by compression before
the spark plug fires. The specific heat ratio of the air-fuel mixture γ
~1.40. Compression ratios for gasoline powered cars range from 10:1
to 14:1 for racing engines. Alcohol powered cars have 15:1; Diesel
14:1 to 23:1.
15. B. Compression
Higher compression means higher power
•Problem - Detonation occurs when the fuel beyond the flame front initiated by
the sparkplug burns. This is also called autoignition or knocking.
•Octane rating proportional to the detonation temperature.
•Higher octane allows higher compression.
•An enormous search found lead, in the form of tetraethyl lead, Pb(C2
H5
)4
,
inhibits detonation. More on this later.
16. C. Timing
Definition of Crank angle, advance vs. retard
Image
• Combustion takes time, about 5 ms.
• Combustion should occur at Top Dead Center (TDC), therefore
spark must precede piston.
• The higher the engine speed (RPM's) the more advanced the
spark must be. Vacuum or centrifugal advance.
• As lower octane fuel is used, the spark must be retarded. Effectively
reduces compression thus reducing power and fuel economy.
• Retarding the spark reduces the maximum and end temperatures
of combustion and thus reduces both CO and NO formation.
17. Image
D. Fuel
An octane rating of 100 means the same antiknock properties as isooctane (2,3,4-
trimethyl-pentane). Without lead in the fuel more aromatic and branched HC must
be mixed into the fuel. But these species are more reactive with respect to
photochemical O3
formation.
Fuel Lead
To produce higher octane gasoline from n-heptane (cheap gasoline) add the
following:
0.8 g Pb per gal. produces 100 octane fuel
0.4 g Pb per gal. produces 90 octane fuel
18. In the United States, lead in gasoline has been phased out altogether, but some of
the developing world still uses lead. Lead forms a solid oxide ash after
combustion, and fouls sparkplugs. To prevent the formation of ash on the plugs,
scavengers such as 1,2-dibromoethane (CH2
Br-CBrH2
) were added to the fuel.
These cause the burned lead to form halides such as Pb(Br) 2
which stay in the
vapor phase longer, and can act as a valve lubricant for some older cars.
Unfortunately, 1,2-dibromoethane is carcinogenic.
Where does the lead go?
•At 20 MPH 90 % of the lead goes onto the exhaust system; 10 % is expelled out
the tailpipe.
•At 70 MPH 90 % of the lead is expelled.
•Most of the lead falls as particles to the ground within 100m of roadways.
19. Lead is an insidious, cumulative poison. High serum (blood) lead has
been linked to reduced intellect, although the research is controversial.
Symptoms are hard to distinguish because they include anemia,
constipation, and abdominal pain, in short the malaise of modern man.
In California cities in 1974 the atmospheric lead concentration was
about 1.5 µg/m3
. The clean air background is about 0.01 µg/m3
.
Essentially all the lead in the air was from automobiles. By 1987 most
American cities had a lead content below 1 µg/m3
; the ambient air
quality standard is 1.5 µg/m3
for an annual average.
20. Diesel Engines
There are no sparkplugs in a diesel engine. The fuel is injected at the
time of maximum compression (near TDC) and the heat of compression
causes combustion.
Diesel Engines have no throttle on the air.
Detonation impossible.
Low octane, "cheap," fuel may be used.
Compression must be higher (ca. 18:1 vs. 9:1 for Otto cycle).
Improved efficiency, but bigger and heavier engine block required.
Fuel mix is leaner, i.e. Φ < 1.0.
Low CO and HC, but high NOx.
Lots of particles including soot and PAH.
21. III. Exhaust Emissions
a) Hydrocarbons
Some fuel remains unburned even after combustion; why? The
Temperature at the time of combustion is 2500 - 3000 C, but the walls of
the cylinder are around 200 C. The exhaust starts at 1000 C, but cools
quickly.
Poor mixing and absorption of HC into oil on walls creates a
quench zone.
HC are concentrated in the first and last components of the exhaust.
The NO profile is opposite.
To control HC emissions from the quench zone, the surface to volume
ratio should be kept to a minimum, but that reduces stroke and
compression.
22. b) Carbon Monoxide
CO2
= CO + 1/2 O2
Keq
= e(-∆G/RT)
The process becomes kinetically limited as expansion occurs. The
formation of CO is quick, but the removal is slower, especially at
temperatures below about 1000 K. Thus the [CO] is close to the [CO]
calculated by the above equilibrium method based on the temperature of
the exhaust gases at the end of expansion.
Image
29. Major advantages, cont.
* Diesel fuel (longer HC chains) is safer than gasoline in many applications. Although
diesel fuel will burn in open air using a wick, it will not explode and does not release a
large amount of flammable vapor. The low vapor pressure of diesel is especially
advantageous in marine applications, where the accumulation of explosive fuel-air
mixtures is a particular hazard. For the same reason, diesel engines are immune to vapor
lock.
* For any given partial load the fuel efficiency (mass burned per energy produced) of a
diesel engine remains nearly constant, as opposed to petrol and turbine engines which use
proportionally more fuel with partial power outputs.
* They generate less waste heat in cooling and exhaust.
* Diesel engines can accept super- or turbo-charging pressure without any natural limit,
constrained only by the strength of engine components. This is unlike petrol engines,
which inevitably suffer detonation at higher pressure.
* The carbon monoxide content of the exhaust is minimal.
* Biodiesel is an easily synthesized, non-petroleum-based fuel (through
transesterification) which can run directly in many diesel engines, while gasoline engines
either need adaptation to run synthetic fuels or else use them as an additive to gasoline
e.g., ethanol added.
30. Diesel engines, Major disadvantages:
•Diesel engines are larger, heavier and more expensive than spark ignited engines.
•Tolerances on valves and rings stricter due to higher compression.
•Noise
•Greater NOx and soot generation
31. Take Home Messages for Internal Combustion Engines.
1.Generate most of the CO and NOx in N America.
2.Four stroke spark ignited engines generate a lot of CO and
substantial NOx.
3.Two-stroke spark ignited engines generate aerosols, CO,
VOC’s, but little NOx.
4.Diesel engines run hot and lean and generate NOx and soot,
but little CO.
32. The Role of Internal Combustion in gaseous
pollution and Photochemical Smog
Formation
The Automobile
Seinfeld Chapt. 3
Wark and Warner Chapt. 10
4. Exhaust Emissions
c) Nitric Oxide, NO
The formation of NO is controlled by kinetics, not thermodynamic
equilibrium. High temperatures favor the formation of NO, and as the
exhaust gases cool the NO is frozen out because the reformation of N2
and
O2
is slow. See Wark and Warner section 8.4. Our objective here is to
derive an expression for the rate at which [NO] approaches the
equilibrium concentration, [NO]eq .
33. The Zeldovich Mechanism (1946)
N2
+ O2
↔ 2NO
Derive an expression for the rate of NO formation.
Equilibrium Calculation
Keq = exp(-∆G /RT) = (PNO
)2
/(PN2
PO2
)
The limit to the formation of NO is the slow rate of N2
dissociation, which
is hindered by a large positive ∆G. Oxygen dissociates more readily.
N2
→ 2N ∆Go
= +217.8 kcal/mole
Keq = 10-158
O2
→ 2O ∆Go
= +110.8 kcal/mole
Keq = 10-81
34. We can represent the formation of NO as a two step process.
O + N2
↔ NO + N (1)
N + O2
↔ NO + O (2)
----------------------
N2
+ O2
↔ 2NO (NET)
d[NO]/dt = k1
[O][N2
] - k-1
[NO][N] + k2
[N][O2
] - k-2
[NO][O] (I)
We will assume that N is in steady state. This is not the same as assuming it
is in thermodynamic equilibrium.
37. In a qualitative sense, at combustion temperature Reaction 1 is fast;
Reaction 2 is fast if there is any O2
around, and Reactions -1 and -2 are
slow. So the formation of NO is much faster than the destruction. As the
temperature drops, O atoms react with each other to reform O2
, preventing
Reaction -2 from removing much NO:
O + O + M → O2
+ M†
The superscript dagger represents translational kinetic energy.
In deriving a quantitative expression for the rate of formation of NO,
the following relations will prove useful. Remember that rate constants
are much harder to measure than thermodynamic properties, thus
thermodynamic data are generally better (more accurate) than kinetic data.
Anywhere we can substitute Keq for k, we will.
39. For a given temperature, Equation IV can be integrated to yield an
expression for the concentration of NO as a function of time, but this is a
tedious process. See Wark and Warner, p. 384. The result is:
[NO]t = [NO]eq ( 1 - (exp(-Mt))1/2
)
Where [NO]eq is the equilibrium concentration of NO and
M = 5.7E15 T -1
P1/2
exp(-58400/T) s-1
Note that M is a strong function of temperature, but not pressure. We have
assumed that Reactions 1 and 2 control, that the temperature is constant
throughout the process, and that N2
and O2
are present at a ratio of 40:1. The
actual process is very complicated because the temperature does not remain
constant.
40. CONCLUSIONS Tuning to Reduce Automotive Pollution Emissions
The kinetics of CO formation and destruction are rapid. The emission of
CO follows thermodynamic equilibrium, and is regulated by the temperature
at the end of combustion. With slow kinetics, NO is seldom in
thermodynamic equilibrium, and the emission is regulated more by the
maximum combustion temperature.
A) Air-Fuel-Mixture
AFR POWER ECONOMY CO/HC NOx
LEAN LOW HIGH LOW HIGH
RICH HIGH LOW HIGH LOW
41. B) Compression
Increases power and reduces CO, but puts structural demands on the
engine, and requires higher octane fuel to prevent knocking. Higher octane
fuel cannot be produced with lead or the catalytic converters will be poisoned.
High octane fuel without lead is more reactive with respect to photochemical
ozone formation.
C) Timing
For maximum power, combustion should take place at the point of
maximum compression, therefore the spark is usually advanced, and occurs
before top dead center. But if a low octane fuel is used with an engine that
has the spark advanced for maximum power, knocking occurs. By retarding
the spark, the octane demand of the engine is reduced. Retarding the spark
also lowers both the maximum temperature and the end temperature of
combustion, reducing both NO and CO production.
42. D) Exhaust gas Recycling
Adding exhaust, rich in relatively inert CO2, N2O and N2, to
the combustion mixture reduces the temperature enough to
help reduce NO production.