机械专业外文文献翻译-外文翻译--柴油发动机工作原理

无锡太湖学院2009届本科生毕业设计（论文）翻译A diesel engine works【Abstract】In a diesel engine cylinder, the piston in the part of the work cycle of compressed gas,and in another part of the work cycle of the combustion gas mixture within the cylinder so the piston top surface expansion high pressure (about 116 120Kgf/cm2)under high temperature (about 569°C) gas role, and the pressure through the piston pin, connecting rod to the crankshaft. Can be seen that the piston is a long time under high temperature and high pressure in continuous reciprocating motion of the load, its load and working conditions were appalling. During the design process of the piston will be designed to ensure long-term stability of the work piston. The design of the work done by a brief introduction as follows:Diesel Engine Piston 180C reasonable processing technology is important, the role of parts and technology program analysis, preparation of rough form and process manufacturing line, through the analysis, comparison, use of the relative concentration of processing programs, and ultimately more reasonable to determine the mechanical line processing. The development process of rough line the main consideration, finishing arrangements, choice of processing methods, centralized and decentralized processes, such as processing the order requirements. Then determine the allowance, process size, after the analysis of the characteristics of the process, select the appropriate processing equipment and technical equipment. Calculated look-up table to determine the next major piston cutting process and the mapping of processes card, the design of the final fixture. Fixture design, it is necessary to take various aspects into account, the strict requirements of the fixture a direct impact on the surface of the workpiece processing position accuracy. Therefore, the machine tool design fixture design is an important task is the processing of one of the most active. During the graduation project in a specially designed positioning accuracy, simple structure and easy-to-use precision pin hole boring jig.Keywords: Piston; Technology; processing equipment; cutting; FixtureAny type of machine that obtains mechanicalenergy directly from the expenditure of the chemical energy of fuel burned in a combustion chamber that is an integral part of the engine. Four principal types of internal-combustion engines are in general use: the Otto-cycle engine, the diesel engine, the rotary engine, and the gas turbine. For the various types of engines employing the principle of jet propulsion, see Jet Propulsion; Rocket. The Otto-cycle engine, named after its inventor, the German technician Nikolaus August Otto, is the familiar gasoline engine used in automobiles and airplanes; the diesel engine, named after the French-born German engineer Rudolf Christian Karl Diesel, operates on a different principle and usually uses oil as a fuel. It is employed in electric-generating and marine-power plants, in trucks and buses, and in some automobiles. Both Otto-cycle and diesel engines are manufactured in two-stroke and four-stroke cycle models.The essential parts of Otto-cycle and diesel engines are the same. The combustion chamber consists of a cylinder, usually fixed, that is closed at one end and in which a close-fitting piston slides. The in-and-out motion of the piston varies the volume of the chamber between the inner face of the piston and the closed end of the cylinder. The outer face of the piston is attached to a crankshaft by a connecting rod. The crankshaft transforms the reciprocating motion of the piston into rotary motion. In multicylindered engines the crankshaft has one offset portion, called a crankpin, for each connecting rod, so that the power from each cylinder is applied to the crankshaft at the appropriate point in its rotation. Crankshafts have heavy flywheels and counterweights, which by their inertia minimize irregularity in the motion of the shaft. An engine may have from 1 to as many as 28 cylinders.The fuel supply system of an internal-combustion engine consists of a tank, a fuel pump, and a device for vaporizing or atomizing the liquid fuel. In Otto-cycle engines this device is either a carburetor or, more recently, a fuel-injection system. In most engines with a carburetor, vaporized fuel is conveyed to the cylinders through a branched pipe called the intake manifold and, in many engines, a similar exhaust manifold is provided to carry off the gases produced by combustion. The fuel is admitted to each cylinder and the waste gases exhausted through mechanically operated poppet valves or sleeve valves. The valves are normally held closed by the pressure of springs and are opened at the proper time during the operating cycle by cams on a rotating camshaft that is geared to the crankshaft. By the 1980s more sophisticated fuel-injection systems, also used in diesel engines, had largely replaced this traditional method of supplying the proper mix of air and