气固界面能量传输机理实验研究

Experimental Investigation on Energy Transport Across the Solid-Gas Interface

为了探讨气-固界面能量传输物理机制,采用实验方法研究了不同压力下氩气-玻璃,水蒸气-玻璃界面附近温度分布和界面吸附特征。结果表明,在两种界面上都存在明显的温度跳跃现象。随着压力的增加,界面温度跳跃值先急剧减小,然后趋于平缓。基于界面吸附特征,分析了两种界面上的能量传输机理。在氩气-玻璃界面,氩气以单原子形式被吸附在界面上,形成阻碍能量传输的附加热阻,因此,压力越高,吸附量越多,界面能量传输能力越弱。对于水蒸气-玻璃界面,水蒸气分子以团簇的形式被吸附在界面上,压力增加,吸附量增多,团簇振动频率类型增加,激发出更多类型的声子在界面传递,从而增强界面的能量传输。

The characteristics of the energy transport and adsorption at the silica-Argon gas and silica-water vapor interfaces are experimentally investigated at different pressures.It is found that the temperatures at the solid-gas interfaces are discontinuous.As the pressure increases,the magnitude of the temperature discontinuity decreases dramatically in the low pressure range,after which it does not change appreciably.Based on the adsorption behaviors at the solid-gas interfaces,the mechanisms of the interfacial energy transport are analyzed.For argon adsorbing on silica,the adsorbate consists of adsorbed atoms and acts as resistance to the heat flux.For water vapor adsorbing on silica,the adsorbate consists of clusters with different number of molecules,enhancing the types of phonons that can be transferred and the heat flux.