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有文献报导采用绝热燃烧室壁可降低油耗、减少散到冷却水的热量并增加废气排放能量,但也有油耗增大的相反报导。文献[1]对此做了物理解释:采用绝热会使燃气和室壁间的温差减小,但壁温的增加使燃气与室壁间的传热系数增大,其增大幅度大大超过了温差减小的幅度,为此修改了传热系数的计算式。本文最近的试验结果进一步证实了上述观点,其中包括传热系数(取决于燃烧室壁温)对增压和非增压发动机性能的影响。
The use of adiabatic combustion chamber walls has been reported to reduce fuel consumption, reduce the amount of heat dissipated to the cooling water and increase the exhaust emission energy, but there are also reports of increased fuel consumption. Literature [1] made a physical explanation for this: the use of adiabatic will reduce the temperature difference between the gas and the chamber wall, but the increase of the wall temperature increases the heat transfer coefficient between the gas and the chamber wall, which greatly exceeds the temperature difference Reduce the magnitude of the heat transfer coefficient to modify the formula. Recent observations in this article further confirm this view, including the effect of heat transfer coefficient (depending on combustion chamber wall temperature) on the performance of supercharged and non-supercharged engines.