【摘要】 用异种气体射流冲击浸没液体中的微电子元件是强化散热的有效方法。本文采用电化学方法测定了液固传质系数,并与传热方法相结合,分离了射流扰动强化对流传热和冷却剂气化产生界面温降强化传热的两种不同效应。更多还原

【Abstract】 Electrodiffusion technique was employed to investigate a particular heat transfer phenomenon of foreign gas jet impingement on minute heat source in liquid bath. In this technique variations of the convective component of the heat flux versus the operating conditions can be estimated from the rate of diffusion-controlled electrochemical reaction, whereby one electrode acts as the heating wall. Combining with conventional heat transfer method, two different contributions to the heat transfer augmentation can be identified experimentally.The heated surface consists of 0. 1mm thick copper foil with the size of 3×3 mm or 5×5 mm exposed to the liquid coolant. The aqueous solution of 0. 005 M K3[Fe(CN)6] + 0. 005 M K4[Fe(CN)6] + 0. 5 M NaOH was selected as liquid medium. The gas injector was placed very closely to the heated surface, and the air jet velocity was in the range of 0-17. 6 m/s.The heat transfer characteristics were studied mainly as functions of gas flow rate, heat flux, and coolant temperature. The results showed that the liquid evaportion exerts very important contribution to the heat transfer of minute heat source, especially at relatively low heat flux. The results were also in good agreement with those predicted by theoratical model.更多还原