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为了了解柴油机燃烧室中燃油与空气的混合及后续燃烧过程，准确地描述燃油雾化和油滴蒸发过程是至关重要的。运用激光衍射法测量液体喷雾粒度具有时喷雾无干扰、设备简单、数据处理迅速等优点，但这种方法对加热环境中的蒸发液雾进行测量时，由于先路上存在的温度及浓度梯度，激光被折射而偏转，测量结果受到严重影响。以往对柴油机喷雾的测量大都是在常温不蒸发条件下进行的，而本文则是通过对粒子激光衍射测量原理的深入分析，对基于激光衍射法的ＭＡＬＶＥＲＮ２６０４Ｃ粒度测量系统加以改进，排除了加热气体中温度和浓度梯度对测量结果的影响，在模拟柴油机燃烧室高温条件下的定容加热装置中，成功地测量不同温度下柴油机喷雾粒度分布，其测量条件为：温度３００～１０００Ｋ，压力０．１～０．５ＭＰａ。结果表明，在保持环境密度不变的条件下，温度在３００～５００Ｋ之间变化时，喷雾的索特平均直径变化不大，而当温度节过５００Ｋ时，喷雾的索特平均直径迅速增加，达到最大值后再缓慢减小。本文对这一实验结果进行了分析。
In order to understand the mixture of fuel and air in the combustion chamber of a diesel engine and the subsequent combustion process, it is of crucial importance to accurately describe the process of fuel atomization and droplet evaporation. The laser diffraction method is used to measure the particle size of the liquid spray with the advantages of no interference when sprayed, simple equipment and rapid data processing. However, when measuring the evaporation mist in the heating environment by the method of laser diffractometry, due to the existence of the temperature and the concentration gradient in the heating path, Reflected and deflected, the measurement results are seriously affected. In the past, the measurement of diesel spray was mostly carried out at room temperature under the condition of no evaporation. In this paper, the principle of particle laser diffraction measurement was further analyzed to improve the particle size measurement system of MALVERN2604C based on laser diffraction, Temperature and concentration gradient on the measurement results, the particle size distribution of diesel spray at different temperatures was successfully measured in a constant volume heating device simulating the high temperature of a diesel engine combustion chamber. The measurement conditions are as follows: temperature 300 ~ 1000K, pressure 0.1 ~ 0.5MPa. The results showed that when the temperature was changed from 300K to 500K, the average diameter of the spray did not change much under the condition of keeping the density of the environment unchanged. When the temperature was over 500K, the mean diameter of the spray increased rapidly, After reaching the maximum decrease slowly. This article analyzes the results of this experiment.