AN APPROXIMATE METHOD OF CALCULATING
THE HEAT TRANSFER COEFFICIENT IN METAL BARS
M. L. Cancillo , J. J. Morales , M. C. Gallego , 
J. M. Vaquero , J. A. Garcia , A. Serrano , and
V. L. Mateos

UDC 621.791

A least-squares method is used to determine the heat 
transfer coefficient H of a solid copper bar in air at constant temperature. 
For this purpose, twelve steady states and their corresponding cooling 
curves were measured with temperature excesses of the metal over the 
surrounding air in the range of 11-74oC and were compared 
to those calculated using a mathematical model to solve the equation 
for the heat flow in the bar. The model reduces an experimental double 
exponential law to an overall single exponential and gives similar 
behavior, within 10% of statistical uncertainty, for H in the steady 
state and in cooling. The values obtained in this study are in qualitative 
agreement with the values given in the literature under similar experimental 
conditions, but there it is not specified how they are obtained in 
solids.