液滴低温气体雾化射流冷却换热理论分析与实验研究

Analysis and experimental study of heat transfer in cryogenic pneumatic mist jet cooling

论述低温气体雾化射流冷却原理及特点,以池内膜态沸腾为基础,将喷雾颗粒的冲击作为一种扰动,建立雾滴射流进入切削区冷却高温壁面的模型,讨论雾滴冷却高温壁面的换热系数,着重探讨工艺参数水流密度对喷雾冷却换热系数的影响。进行了不同水剂量的低温气体雾化射流冷却钛合金高温壁面的瞬态实验,获得了钛合金试件表面温度分别为100℃、150℃、200℃和250℃时,低温气体雾化射流冷却达到最佳冷却效果时水剂量,分析了水剂量对冷却效果的理论依据,结果证实该模型对实际应用具有一定的指导作用。

Discusses the principle and characteristic of cryogenic pneumatic mist jet cooling. Based on the pool film boiling, the jet is regard as the disturbance on it. It founds a model of fogdrop jet in pouring cutting area to cool high temperature wall, and discusses the heat transfer coefficient. The effect of water density on spray cooling heat transfer coefficient is emphatically analyzed. The experiment on cooling effect in cryogenic pneumatic mist jet cooling Ti-6Al-4V alloy surface is put up with different water density and the bestest water density in test sample with the temperature of 100℃, 150℃ ,200℃ and 250℃ is got. Theoretical basis of water density to cutting effect is discussed, the result proved was instructive in actual application.