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前言设计大功率柴油机,最重要的是要能予知燃烧室另件的温度分布,并保证它们不超过极限温度,使应力保持在安全水准以内。目前,用复杂的计算程序来予算这种温度分布已成为一种常规的计算方法。但是,这种予算的精度在很大程度上取决于估计另件边界热交换条件的准确性。虽然有很多柴油机热交换的资料,但有关燃烧室壁热交换三维变化的详细资料却很少、甚至没有。大功率柴油机活塞和气缸套同燃气或冷却液接触的边界就是这样一种重要的边界。 W.J.Seale和D.H.C.Taylor已经测得活塞与气缸套的燃气侧、气缸套冷却水侧和活塞冷却油侧的放热系数。在活塞头径向找到了一种简单径向变化的热交换规律。最大放热系数的位置与最大空气浓度出现的位置是一致的。在每个半径上热交换的径向变化最多只与
Foreword The design of high-power diesel engine, the most important thing is to know the temperature distribution of the other components of the combustion chamber, and ensure that they do not exceed the limit temperature, so that the stress remain within the safe level. Currently, using complex computational procedures to calculate this temperature distribution has become a routine method of calculation. However, the precision of this calculation depends to a large extent on the accuracy of estimating the heat exchange conditions at the other component boundary. Although there are many sources of diesel engine heat exchange, there is little or no detail on the three-dimensional changes in heat exchange in the combustion chamber wall. The boundary of a high-power diesel piston and cylinder liner in contact with gas or coolant is such an important boundary. W.J.Seale and D.H.C.Taylor have measured the exothermic coefficient of the gas side of the piston and cylinder liner, the cooling water side of the cylinder liner, and the piston cooling oil side. In the piston head radial to find a simple radial variation of the heat exchange law. The location of the maximum exotherm is consistent with where the maximum air concentration appears. Radial changes in heat exchange at each radius are limited to a maximum of