衣服の保温性能評価指標としての人体周囲空気層における熱移動特性  [in Japanese] Heat Transfer Characteristics of Air Boundary Film around the Human Body for the Thermal Function of Clothes  [in Japanese]

Heat transfer coefficients for heat transfer across an air layer (boundary film) around glass bottles (250ml-20l) have been measured as a model for determining heat transfer coefficients around the human body. Overall heat transfer coefficients obtained from an unsteady-state method coincided with those from a steady-state method. The heat transfer coefficient of air boundary film is determined from the overall heat transfer coefficient by taking into account the heat transfer across the insulated part and that within the bottle. The heat transfer coefficient is the sum of the radiation and convection transfer coefficients. The radiation transfer coefficient can be determined theoretically. The heat transfer coefficient obtained for natural convection differed little from the coefficients of simple-shaped bodies such as a vertical wall, a horizontal pipe and so on. The coefficients correlated with the diameter of the bottles and temperature differences within boundary film. The heat transfer coefficient obtained for forced convection also coincided with those of a pipe and a sphere without any significant differences. The coefficients correlated with the diameter of the bottles and wind speed.