AN INVESTIGATION OF THE ENHANCEMENT OF HEAT TRANSFER AS QUICK COOLING OF THE HEATED PLATE

当热板被冷却剂冷却时，热板被加热到高温时被蒸汽层覆盖。因此，热板传热的减少是通过蒸汽层的热阻来实现的。本文的研究目的是寻找通过对蒸汽层进行扰动来增强传热和提高热板冷却效果的方法。(1)关于液-气界面的化学性质和稳定性的评价液-气界面的振动受液体的界面张力的影响。液汽界面动力学不稳定性理论对界面张力的影响提出了一些建议。在冷却剂（水）中加入表面活性剂，对界面张力的影响进行了实验研究。实验明确地表明，表面活性剂的加入对蒸汽层的存在有有利的影响。在添加表面活性剂的情况下，膜沸腾保持在低热流密度区域，并且蒸汽层已经存在了一定的时间。虽然我们最初预计较低的界面张力会加速液体与热板表面的接触。(2)关于热板表面粗糙度的影响我们研究了热板源面粗糙度的影响，发现源面粗糙度大或污染大，冷却剂与表面接触容易。金属丝网覆盖在印版上，尤其干扰了汽膜层的存在。

In case of cooling of hot plate by the coolant, the hot plate is covered with the vapor layr when it was heated to high temperature. Consequently, the reduction of heat transfer from the hot plate is produced by means of the thermal resistance of vapor layr. The object of our investigation is to find the meth- ods of the enhancement of heat transfer by making of disturbance to the vapor layr and to increase the cooling effects of the hot plate.(1) On the ralation of the chemical properties and the stability of the liquid-vapor interfaceThe vibration of liquid-vapor interface is affected by the interfacial tension of liquid. The kinetic instability theory of liquid-vapor interface gives some suggestions an influence of the interfacial tension. An experimental investigation of the effects of interfacial tension carried out by addition of a surface active agent into the coolant (water). It has been definitely shown by experiments that the addition of a surface active agent has a favorable influence upon the existence of vapor layr. In case of addition of a surface active agent, the film boiling are maintaining at low heat flux region and the vapor layr has been existed for any length of time. Although we expected initialy that an lower interfacial tension accelerates the touch of the liquid to the hot plate surface.(2) On the effect of the hot plate surface roughnessWe have investigated the effect of sourface roughness of hot plate and found that large roughness or contaminations on sourface made easy to contact of coolant and surface. The metal wire nets covered on the plate, especially, disturbed the existence of the vapor film layr.