Towards a theory of the surface conductance coefficient in solids

Experiments were conducted with a standard cylindrical copper bar 42 cm long and 2.5 cm in diameter to see in the steady-state and cooling temperature distributions satisfied a single exponential law and yielded the same value for the surface conductance coefficient, H. The results are compared with those of identical experiments reported for iron, aluminum, and polymethyl methacrylate bars. It is found that the steady-state value of H is a factor of 4 smaller than the cooling value. A single exponential law is an acceptable description of the cooling. The results are in excellent agreement with those for iron; the agreement is fair for aluminum and poor for polymethyl methacrylate. (AIAA)