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供油提前角是影响柴油发动机性能的重要因素之一。每种柴油机均有一个最佳的供油提前角。而各型柴油机的供油提前角,仅仅是指在某种转速下(一般柴油机为标定工况转速)的最佳供油提前角,随转速的改变,其最佳供油提前角是一个变值。因柴油机转速增加时,燃烧室内的气流运动得到加强,改变了燃料与空气的混合,使燃烧过程加快,这时燃烧过程所占用的时间减少,但不能与转速升高成正比地减少,然而,单位时间内的曲轴转角却是随转速增加而成正比地增加,燃烧过程有可能延续到膨胀冲程,致使燃烧恶化,部分燃油来不及完全燃烧而排出。为了解决这一问题,目前一些载重汽车上的柴油发动机(工作中转速变化幅度大)配用了供油角度自动提前器,就
Fuel supply advance angle is one of the important factors affecting diesel engine performance. Each diesel engine has an optimum fuel advance angle. The various types of diesel engine oil advance angle, just refers to the speed of a certain speed (the general condition of the diesel engine calibration speed) the best fuel supply advance angle, with the speed change, the best fuel supply advance angle is a variable value. Due to the increased speed of the diesel engine, the airflow in the combustion chamber is strengthened and the mixture of fuel and air is changed to accelerate the combustion process. At this time, the time consumed in the combustion process is reduced but can not be reduced in proportion to the increase of the rotational speed. However, The crank angle per unit time increases proportionally with the increase of the speed, and the combustion process may extend to the expansion stroke, causing the combustion to deteriorate, and some of the fuel may not be able to completely be discharged during combustion. In order to solve this problem, at present, some diesel engines on trucks (large variations in speed at work) are equipped with an automatic oil supply angle advancer