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采用一步总包有限反应速率模型模拟了不同相对速度、颗粒尺寸、环境温度条件下单个油滴燃烧。对于全包围燃烧模态,火焰半径的模拟结果与文献的理论解析解进行对比,在周向角小于90°范围内和数值模拟结果接近,大于90°,理论解不能精确预测火焰锋面半径;油滴表面局部蒸发率较尾部火焰燃烧模态下的蒸发率小;各个燃烧模态下,局部蒸发率最大的位置发生在前驻点处。燃烧状态下油滴颗粒的阻力系数要比冷态条件下的阻力系数小,不能简单套用Wallis-Kliachko公式计算。阻力系数随着来流速度增大而增大,随着周围环境温度的升高而升高。
A one-step total package finite reaction rate model was used to simulate the combustion of a single oil drop with different relative velocities, particle sizes and ambient temperature. For the whole combustion mode, the simulation results of the flame radius are compared with the theoretical analytical solutions of the literature. When the circumferential angle is less than 90 ° and the numerical simulation results are close to more than 90 °, the theoretical solution can not accurately predict the flame front radius. The local evaporation rate is lower than that of the tail flame combustion mode. Under each combustion mode, the location with the largest local evaporation rate occurs at the former stagnation point. Under the condition of combustion, the resistance coefficient of oil droplet particles is smaller than the resistance coefficient under cold conditions, which can not be simply calculated by the Wallis-Kliachko formula. The drag coefficient increases as the incoming velocity increases and increases as the ambient temperature increases.