AStudy of the measuring 皿 ethod and error of coefficient of heat transfer by convection for the interior walls have been studied using the appratus for meas ロ ing the air temperature near the sur − face of a wall .Ωuantity Q 正heat f1Qw by cQvectiQn a 匸e assessed from multiphng the air temperature gradient at the snrface by thermal conductivity of air . The apparatus is therefore designed so that the air temperature of the thermal boundary layer is measured by a O . 05 mm diameter , CA

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... le mounted , to move near or away from the sur − face and ho且 ding it at any predetermined distance . The follQwlng can be deduced from experimental results ; 1. It has been made known that ;1 ) wall surface proximity air temperature is relatively stable within l mm the wall surface , and 2 ) air temperature distribution becomes linear up to 2. 5 mm from the wall surlace . 2, Taking care of the difference between a surface to be measured and a thermocouple , this − method can be weU used ヒ Q the measurement of surface tmperature in the measurement of heat transfer coefficient . 3. This method enables the measurement of heat transfer coefficient in a shorr time ( approx . in 8 min . )in order to induce the surface tempera加 re from the wall surface . proximity air temperature substantially without disturbing