A study of the Convection Heat Transfer Coefficient for the Interior Walls of Building

本文研究了用壁面附近空气温度测量仪测量室内壁面对流换热系数的方法和误差。对流热流的数量是通过将地表的空气温度梯度乘以空气的导热系数来计算的。墙的对流换热系数的值是通过每平方米每小时离开墙表面的对流热量除以墙表面与距离墙表面10cm的空气之间的温度差得到的。因此，该装置的设计使得热边界层的空气温度可以通过安装的直径为0.05mm的CA热电偶来测量，以靠近或远离表面并保持在任何预定的距离（例如0.25、0.5、1、2、3、4mm）。与其他方法相比，该方法耗时短，且不干扰表面状况。墙体局部对流换热系数的最大值和最小值分别出现在距离地面约50cm和25cm的连续距离处将中心沿壁面的对流换热系数与壁面拐角处的对流换热系数进行比较，得到的壁面拐角处的对流换热系数小于中心处的对流换热系数。

A Study of the measuring method and error of coefficient of heat transfer by convection for the interior walls have been studied using the appratus for measuring the air temperature near the surface of a wall.Quantity of heat flow by convection are assessed from multipling the air temperature gradient at the surfce by thermal conductivity of air.Values of the coefficient of heat transfer by convection for a wall are obtained by dividing the convection heat leaving the wall surface per square meter per hour by the temperature difference between the surface and the air 10cm away from the surface. The apparatus is therefore designed so that the air temperature of the thermal boundary layer is measured by a 0.05mm diameter,CA thermocouple mounted,to move near or away from the surface and holding it at any predetermined distance.(e.g.0.25,0.5,1,2,3,4mm from surface) The following can be deduced from experimental results;1.Comparing with the other methods this method takes a shorter time and dose not disturb the surface condition.2.The maxmum and minimum value of the local heat transfer coefficient by convection for a wall is found at the distances approximately 50cm and 25cm consecutivity from the floor.3 Comparing the convection heat transfer coefficient along the wall at the center,with heat transfer coefficient at the corner of the wall,the value obtained at the corner is smaller than the value at the center.