油滴与高温固体壁面碰撞的流动与传热及飞溅特性  

Flow-Heat Transfer and Splash Characteristics of Oil Droplets Impacting onto Heated Solid Wall

作　　者：黄杨明 陈薄[1] 古忠涛[1] HUANG Yangming;CHEN Bo;GU Zhongtao(School of Manufacturing Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China)

机构地区：[1]西南科技大学制造科学与工程学院,四川绵阳621010

出　　处：《西南科技大学学报》2024年第1期85-92,共8页Journal of Southwest University of Science and Technology

基　　金：国家自然科学基金项目(51475395)。

摘　　要：考虑油滴(油膜)/固体壁面接触角动态变化和油液热力学特征参数受温度影响,基于流体体积法建立了油滴与高温固体壁面碰撞的三维流动与传热数值计算模型,通过试验验证了数值计算模型的正确性。基于数值计算模型,分析了油滴碰撞高温固体壁面后的流动与传热及飞溅特性,以试验和数值计算结果为基础,建立了描述油膜铺展/飞溅临界判据。结果表明:油滴碰撞高温固体壁面后的状态与碰撞条件有关,破碎、飞溅有利于油膜的铺展流动;二次油滴是油膜边缘破碎产生的油带断裂而成,大直径二次油滴分裂为小直径油滴;随油膜铺展进程,壁面平均热流密度增大,而油膜的径向热流密度则逐渐减小;增大碰撞速度、油滴直径和润滑油温度,有利于油膜的破碎与飞溅,二次油滴数量和下飞溅角均随之增大。Considering the dynamic changes between the oil droplet(oil film)and the contact angle of solid wall and the influence of temperature on the characteristic parameters of oil thermodynamics,a three-dimensional flow and heat transfer numerical calculation model for the impact between oil droplets and heated solid wall was established based on the volume of fluid method,and the correctness of the numerical calculation model was verified through experiments.Based on the numerical calculation model,the flow-heat transfer and splash characteristics of oil droplets and heated solid wall after impact were analyzed.Based on the experimental and numerical calculation results,the critical criterion of oil film spreading/splash was established.The results show that the state of oil droplets after impact is affected by the impact conditions.Breaking and splashing are conducive to the oil film spreading flow.Secondary oil droplets are formed by the fracture of oil bands caused by the breaking of oil film edge.The larger diameter secondary oil droplets split into small diameter oil droplets.During the spreading process of the oil film,the average heat flux on the wall increases,while the radial heat flux of the oil film gradually decreases.Increasing the impact speed,oil droplet diameter and lubricating oil temperature is conducive to the breaking and splashing of the oil film,and the number of secondary oil droplets and the lower splash angle are increased accordingly.

关 键 词：油滴碰撞 高温固体壁面 流动与传热 飞溅特性 飞溅临界 

分 类 号：V233.4[航空宇航科学与技术—航空宇航推进理论与工程]