Pdf diesel engine fundamentals

You should take every opportunity to learn all you can about diesel engines. This text, by a leading authority in the field, presents a fundamental and factual development of the science and engineering underlying the design of combustion engines and turbines. An extensive illustration program supports the concepts and theories discussed.

Diesel Technology covers the construction, operation, service, and repair of two- and four-stroke diesel engines. This textbook details developments in engine control computers, fuel management systems, and emission control systems. Publisher's Note: Products purchased from Third Party sellers are not guaranteed by the publisher for quality, authenticity, or access to any online entitlements included with the product.

The long-awaited revision of the most respected resource on Internal Combustion Engines --covering the basics through advanced operation of spark-ignition and diesel engines. Written by one of the most recognized and highly regarded names in internal combustion engines this trusted educational resource and professional reference covers the key physical and chemical processes that govern internal combustion engine operation and design.

Internal Combustion Engine Fundamentals, Second Edition, has been thoroughly revised to cover recent advances, including performance enhancement, efficiency improvements, and emission reduction technologies. You will get complete explanations of spark-ignition and compression-ignition diesel engine operating characteristics as well as of engine flow and combustion phenomena and fuel requirements. The text offers comprehensive coverage of every NATEF task with clarity and precision in a concise format that ensures student comprehension and encourages critical thinking.

Providing a comprehensive introduction to the basics of Internal Combustion Engines, this book is suitable for: Undergraduate-level courses in mechanical engineering, aeronautical engineering, and automobile engineering.

Postgraduate-level courses Thermal Engineering in mechanical engineering. Section B courses in mechanical engineering. In addition, the book can be used for refresher courses for professionals in auto-mobile industries.

Coverage Includes Analysis of processes thermodynamic, combustion, fluid flow, heat transfer, friction and lubrication relevant to design, performance, efficiency, fuel and emission requirements of internal combustion engines. Special topics such as reactive systems, unburned and burned mixture charts, fuel-line hydraulics, side thrust on the cylinder walls, etc.

Modern developments such as electronic fuel injection systems, electronic ignition systems, electronic indicators, exhaust emission requirements, etc. The Second Edition includes new sections on geometry of reciprocating engine, engine performance parameters, alternative fuels for IC engines, Carnot cycle, Stirling cycle, Ericsson cycle, Lenoir cycle, Miller cycle, crankcase ventilation, supercharger controls and homogeneous charge compression ignition engines.

Besides, air-standard cycles, latest advances in fuel-injection system in SI engine and gasoline direct injection are discussed in detail. This process is repeated fourteen times as the air flows from the first stage through the fourteenth stage.

Figure shows one stage of the compressor and a graph of the pressure characteristics as the air flows through the stage. In addition to the fourteen stages of blades and vanes, the compressor also incorporates the inlet guide vanes and the outlet guide vanes. These vanes, located at the inlet and the outlet of the compressor, are neither divergent nor convergent. The inlet guide vanes direct air to the first stage compressor blades at the "best" angle.

The outlet guide vanes "straighten" the air to provide the combustor with the proper airflow direction. During design, every effort is made to keep the air flowing smoothly through the compressor to minimize airflow losses due to friction and turbulence.

This task is a difficult one, since the air is forced to flow into ever-higher pressure zones. Air has the natural tendency to flow toward low-pressure zones.

If air were allowed to flow "backward" into the lower pressure zones, the efficiency of the compressor would decrease tremendously as the energy used to increase the pressure of the air was wasted. To prevent this from occurring, seals are incorporated at the base of each row of vanes to prevent air leakage.

In addition, the tip clearances of the rotating blades are also kept at a minimum by the use of coating on the inner surface of the compressor case. All components used in the flow path of the compressor are shaped in the form of airfoils to maintain the smoothest airflow possible.

Just as is the case for the wings of an airplane, the angle at which the air flows across the airfoils is critical to performance.

Any deviation from the maximum rated speed changes the characteristics of the airflow within the compressor. The blades and vanes are no longer positioned at their optimum angles.

Many engines use bleed valves to unload the force of excess air in the compressor when it operates at less than optimum speed. The example engine incorporates four bleed valves at each of the fifth and tenth compressor stages. This results in higher air velocities over the blade and vane airfoils, improving the airfoil angles.

The potential for airfoil stalling is reduced, and compressor acceleration can be accomplished without surge. Diffuser Air leaves the compressor through exit guide vanes, which convert the radial component of the air flow out of the compressor to straight-line flow. The air then enters the diffuser section of the engine, which is a very divergent duct. The primary function of the diffuser structure is aerodynamic. As a result, the highest static pressure and lowest velocity in the entire engine is at the point of diffuser discharge and combustor inlet.

Other aerodynamic design considerations that are important in the diffuser section arise from the need for a short flow path, uniform flow distribution, and low drag loss.

Combustor Once the air flows through the diffuser, it enters the combustion section, also called the combustor. The combustion section has the difficult task of controlling the burning of large amounts of fuel and air.

It must release the heat in a manner that the air is expanded and accelerated to give a smooth and stable stream of uniformly-heated gas at all starting and operating conditions.

This task must be accomplished with minimum pressure loss and maximum heat release. In addition, the combustion liners must position and control the fire to prevent flame contact with any metal parts. The engine in this example uses a can-annular combustion section. Six combustion liners cans are positioned within an annulus created by inner and outer combustion cases. Combustion takes place in the forward end or primary zone of the cans. The remaining air, referred to as secondary or dilution air, is admitted into the liners in a controlled manner.

The secondary air controls the flame pattern, cools the liner walls, dilutes the temperature of the core gasses, and provides mass. It is important that the fuel nozzles and combustion liners control the burning and mixing of fuel and air under all conditions to avoid excess temperatures reaching the turbine or combustion cases.

The rear third of the combustion liners is the transition section. The transition section has a very convergent duct shape, which begins accelerating the gas stream and reducing the static pressure in preparation for entrance to the turbine section. Turbine This example engine has a four-stage turbine. The turbine converts gaseous energy into mechanical energy by expanding the hot, high-pressure gases to a lower temperature and pressure.

Each stage of the turbine consists of a row of stationary vanes followed by a row of rotating blades. This is the reverse of the order in the compressor. In the turbine, the stator vanes increase gas velocity, and then the rotor blades extract energy. The vanes and blades are airfoils that provide for a smooth flow of the gases.

As the airstream enters the turbine section from the combustion section, it is accelerated through the first stage stator vanes. The stator vanes also called nozzles form convergent ducts that convert the gaseous heat and pressure energy into higher velocity gas flow Pi. In addition to accelerating the gas, the vanes "turn" the flow to direct it into the rotor blades at the optimum angle. As the mass of the high velocity gas flows across the turbine blades, the gaseous energy is converted to mechanical energy.

Velocity, temperature, and pressure of the gas are sacrificed in order to rotate the turbine to generate shaft power. Figure represents one stage of the turbine and the characteristics of the gases as it flows through the stage. The efficiency of the turbine is determined by how well it extracts mechanical energy from the hot, high-velocity gasses.

Since air flows from a high-pressure zone to a low- pressure zone, this task is accomplished fairly easily. The use of properly positioned airfoils allows a smooth flow and expansion of gases through the blades and vanes of the turbine. All the air must flow across the airfoils to achieve maximum efficiency in the turbine. In order to ensure this, seals are used at the base of the vanes to minimize gas flow around the vanes instead of through the intended gas path.

In addition, the first three stages of the turbine blades have tip shrouds to minimize gas flow around the blade tips. Exhaust After the gas has passed through the turbine, it is discharged through the exhaust.

Though most of the gaseous energy is converted to mechanical energy by the turbine, a significant amount of power remains in the exhaust gas. The first metal the hot gases from the combustion section strike is the turbine inlet. The temperature of the gas stream is carefully monitored to ensure that overtemperature does not occur.

Sample Engine Pressure, Temperature, and Velocity Compromises are made in turbine design to achieve the optimum balance of power, efficiency, cost, engine life, and other factors. As an example, our sample engine can operate at a higher turbine inlet temperature than previous models due to improved materials and design. The higher temperature allows for increased power and improved efficiency while adding higher cost for the direct cooling of the first turbine stage airfoils and other components.

At a constant speed, the compressor pumps a constant volume of air into the engine with no regard for air mass or density. If the density of the air decreases, the same volume of air will contain less mass, so less power is produced. If air density increases, power output also increases as the air mass flow increases for the same volume of air.

Atmospheric conditions affect the performance of the engine since the density of the air will be different under different conditions. On a cold day, the air density is high, so the mass of the air entering the compressor is increased. As a result, higher horsepower is produced. Even if you already have some background knowledge, this course will serve as an efficient refresher, whatever your level of understanding, or engineering background HVAC, power engineering, oil and gas, chemical engineering, mechanical engineering etc.

Interactive 3D models are used extensively to show you each individual engine component and how these components work together to complete useful work. The course is packed with images, 2D animations, interactive 3D models, 3D animations and high quality written content. Written content has been read aloud so that you can 'learn on the go' without needing to watch the screen constantly.

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