发动机 英语ppt.ppt

The main content of my speech Engine The internal combustion engine Green Car * Heat engine internal combustion engines external combustion engines 活塞式 叶片式 Definition：The engine is a machine designed to convert energy into useful mechanical motion Classification： 返回 1.The Definition and Classification of the Engine 2.Internal combustion engines What is the internal combustion engine？ The internal combustion engine is an engine in which the combustion of a fuel (generally, fossil fuel) occurs with an oxidizer (usually air) in a combustion chamber. How does the engine work？ In an internal combustion engine the expansion of the high temperature and high pressure gases, which are produced by the combustion, directly applies force to components of the engine, such as the pistons or turbine blades or a nozzle, and by moving it over a distance, generates useful mechanical energy The internal combustion engine may be classified in several ways： Type of cooling system Cylinder arrangement The internal motion Number of cycles 2.1 The Classification of the internal combustion Engine Type of cooling Water-cooling engine air-cooling engine in-line or stright engines Arrangement of cylinders（气缸） V-engines Opposed cylinder engine  往复活塞式 reciprocating engine（活塞式） rotary engine（转子式） The internal motion Two-stroke engine Four-stroke engine Number of cycles 2.2 The Basic Component of the Four-stroke engine Valve mechaisms Crankshaft and connection rod mechaisms Lubication system Fuel injection system Cooling system Ignition system Exhaut systems Twe mechaisms: Five system: As their name implies, four-stroke internal combustion engines have four basic steps that repeat with every two revolutions of the engine: Intake/suction stroke Compression stroke Power/expansion stroke Exhaust stroke 2.3 Principles of Four-stroke Internal Combustion Engine Company Logo 1.Intake/suction stroke The inlet valve opens The outlet valve closes T: 370~440 K p: