为了了解柴油机气缸内的工作情况,在试验时往往需要测绘示功图。所谓示功图就是表明气缸内工作气体的压力随着曲轴转角的变化(也就是随着活塞在气缸内位置的变化)而变化的线图。对于内燃机车用柴油机,目前我们多采用气电示功器来进行示功图的测绘。由气电示功器所得到的示功图在正常的情况下有如附图所示的形状。它不仅告诉我们柴油机气缸内的工作是否正常 In order to understand the work of the diesel engine cylinder, the test often need to plot the dynamometer. The so-called dynamometer is a diagram that shows how the working gas pressure in the cylinder changes as the crank angle changes (ie as the piston changes in the cylinder). For diesel locomotive diesel engines, at present, we use more gas dynamometer to plot the dynamometer. The dynamometer obtained from the pneumatic dynamometer has a shape as shown in the drawings under normal circumstances. It not only tells us whether the work inside the diesel engine cylinder is normal