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为深入理解不同壁面温度下的燃料油膜蒸发特性,对热重分析法和石油产品馏程测定法进行了比较．采用热重分析法在不同气氛流量和不同升温速率下,研究了不同初始厚度的90#汽油、93#汽油和0#柴油油膜的蒸发特性,分析了加热速率、油膜厚度和气氛流量等对油膜蒸发的影响．结果表明,燃料在热重分析仪中所处的状态和环境接近内燃机中油膜的实际情况,所得结果可用于分析发动机内燃料油膜的蒸发规律;热重分析仪能用来模拟影响油膜蒸发的主要因素,可以对加热速率和油膜厚度等影响因素进行定量的基础研究;要实现油膜较快地完全蒸发,首先要有足够高的壁面温度;提高升温速率和减小油膜厚度将缩短油膜蒸发时间;强烈的气流运动对加快油膜蒸发非常重要．加热速率为100℃／min时所得的结果,对研究柴油机冷起动和暖机工况下的油膜蒸发很有参考价值;在快速蒸发过程中,分子间强烈的相互作用使多组分互溶性混合物的蒸发并不严格按照各组分的沸点从低到高依次进行,高沸点组分会在未达到其沸点之前就已挥发;对0#柴油,若壁面温度达到250℃,着壁油膜即能充分蒸发．
In order to further understand the evaporation characteristics of fuel film at different wall temperatures, the thermogravimetric analysis and petroleum product distillation range determination were compared. The evaporation characteristics of 90 # gasoline, 93 # gasoline and 0 # diesel oil film with different initial thickness were studied by thermogravimetry at different atmosphere flow rates and different heating rates. The effects of heating rate, oil film thickness and atmosphere flow on the oil film Effect of evaporation. The results show that the state and environment of the fuel in the TGA are close to the actual situation of the oil film in the internal combustion engine. The obtained results can be used to analyze the evaporation law of the fuel film in the engine. The TGA can be used to simulate the main Factors that can be heated on the rate and the thickness of the oil film and other influencing factors for quantitative basic research; to achieve complete evaporation of oil film faster, we must first have a sufficiently high wall temperature; increase the heating rate and reduce the film thickness will shorten the evaporation time; Strong air movement to speed up the film evaporation is very important. The results obtained at a heating rate of 100 ° C / min are of great value in the study of oil-film evaporation under cold and warm-up conditions of diesel engines. In the rapid evaporation process, the strong intermolecular interaction makes multi-component miscible mixtures Of the evaporation is not strictly in accordance with the boiling point of each component from low to high in turn, high boiling point components will not reach its boiling point before evaporation; 0 # diesel, if the wall temperature reaches 250 ℃, the wall oil film that is sufficient evaporation.