A droplet injected from the engine nozzle at high speed generally exhibits a non-spherical shape due to aerodynamic pressure on the droplet surface. The non-spherical shape of a droplet affects its convective heat transfer, heating, and evaporation. Droplet evaporation is critical in heat transfer. The effect of a droplet's non-sphericity on evaporation is investigated in this paper, under the assumption that droplet shapes are prolate or oblate spheroids. Analytical evaporation rates and heat transfer enhancement factors under forced convection for both prolate and oblate spheroidal droplets are derived. The effects of droplet aspect ratio, volume, and Reynolds number on the droplet evaporation under different conditions are numerically investigated. The results indicate that the evaporation conversion rates for both prolate and oblate spheroids are enhanced compared to a spherical droplet of the same volume. In addition, larger droplets show an increased enhancement effect on the evaporation process. Assuming that the droplet shrinkage reduces the dimension perpendicular to the droplet surface, the spheroidal droplet maintains its original aspect ratio during the evaporation process in a quiescent environment, while the nonspherical droplet tends to increase its sphericity under a forced convection situation.

由于液滴表面上的空气动力压力，从发动机喷嘴高速喷射的液滴通常呈现非球形形状。液滴的非球形形状会影响其对流传热、加热和蒸发。液滴蒸发在传热中至关重要。在假设液滴形状是扁长球体或扁球体的情况下，本文研究了液滴的非球形度对蒸发的影响。推导出长球状和扁球状液滴在强制对流下的分析蒸发率和传热增强因子。数值研究了液滴纵横比、体积和雷诺数对不同条件下液滴蒸发的影响。结果表明，与相同体积的球形液滴相比，长球体和扁球体的蒸发转化率均提高。此外，较大的液滴显示出对蒸发过程的增强效果。假设液滴收缩降低了垂直于液滴表面的尺寸，在静止环境下的蒸发过程中，球形液滴保持其原始纵横比，而非球形液滴在强制对流情况下倾向于增加其球形度。