《内燃机理论及构造》结构、工作原理.ppt

The Inline Engine We all know the engine is the heart of the automobile. What is the core of the engine? Yes, it’s the cylinder. Most cars have more than one cylinder (four, six and eight cylinders are common). In a multi-cylinder engine, the cylinders usually are arranged in one of three ways: inline, V or flat. In an inline engine, the cylinders are arranged in a line in a single bank. The inline arrangement is the simplest and most common one and has many advantages. First, the engine has a good stability and more power. Second, the structures of the cylinder block and the crankshaft are very simple and they share only one cylinder head. The cost to manufacture and install is less. Because of these advantages, BMW and also many American car manufactures like to use the inline cylinder engine. This kind of engine is widely used in the cars made in home. 1-2 Basic Terms of Engine 发动机基本术语 TDC = top dead center, top center, outer dead center 上止点 BDC = bottom dead center, bottom center, inner dead center 下止点 S = piston stroke, piston travel 活塞行程 Sk = piston clearance from TDC 活塞离上止点距离 r = crank radius 曲柄半径 φ = crank angle, crankshaft angle 曲柄角 Vh = swept volume of a cylinder或piston displacement或 cylinder swept volume 气缸工作体积，每缸排量 VC = combustion volume或 combustion chamber (space) volume 或 cylinder compression volume 燃烧室容积 VC + Vh = cylinder total volume 气缸总容积 （VC + Vh）/ VC = compression ratio 压缩比 Main Terms There are many terms in describing the operations of an automobile engine. Let’s see some basic terms. Stroke refers to piston movement. A stroke occurs when the piston moves from one extreme position to the other extreme posit