Experiment on the Heat-Transfer of Oil-Cooling Pipe

Abstract

The author wishes to perform an exact experiment, in accordance with the law of similarity he has worked out. Here, the similarity is that the mean temperature θ_m of passing oil flow depends not only on G_z=Wc/kL but also on s'=(t_i-t_w)/(t_i-t_∞) and K=ω/R(t_i-t_∞), and these two groups are dimensionless quantities. The author carried out a series of experiments on the relation of θ_m to G_z under the condition that s'and K were kept at constant values. And the values of s'and K were varied in another series of experiments by changing the oil or temperature ranges. As a result it was confirmed that the curves of θ_m to G_s were different from the Nusselt's curve and from one another by the values of s'or K, thus proving the validity of the similarity as proposed by the author.