低沸点燃料内气泡生长简化模型的建立

Development of a Simplified Model of Bubble Growth for Fuels with Lower Boiling Point

基于对过热液体内气泡生长的一维数值模型的研究,根据气泡表面的热边界层内温度分布的定性分析,构建了一个简化的气泡生长模型.分别利用过热水中气泡生长的试验数据和二甲醚(DME)一维气泡生长模型的计算数据对模型的有效性进行了验证,结果表明,简化的气泡生长模型不仅保持了一维气泡生长模型的准确性,还大大降低了计算成本.利用该模型对二甲醚在过热条件下的气泡生长过程进行了数值模拟,结果表明,在表面张力控制阶段,气泡生长主要受表面张力的影响,在传热控制阶段,气泡生长主要受热扩散系数的影响,而在过渡阶段,气泡生长则同时受表面张力和热扩散系数的影响.

A simplified model for bubble growth was developed according to qualitative analysis of tem- perature profile in the thermal boundary layer of the vapor bubble. The model is based on the study of one- dimensional bubble growth model under the superheated conditions. The model is validated by the experi- mental data of vapor bubble growth in the superheated water and the numerical solution of dimethyl ether （DME） vapor bubble growth using the one-dimensional bubble growth model respectively. Compari- son shows that the model gives good accuracy and reduced computational cost than those of one- dimensional bubble growth model. Using the model, the DME bubble growth is simulated under the su- perheated conditions. The result shows that surface tension plays an important role in the controlled do- main of surface tension for bubble growth, and heat transfer controlled domain of bubble growth is con- trolled by thermal diffusivity while in the transition domain both surface tension and thermal diffusivity influence the bubble growth.