Part I. Temperature gradients in turbulent gas streams effect of viscous dissipation on the evaluation of total conductivity. Part II. Thermal transfer from small wires in the boundary flow about a cylinder

[摘要] Part I. Values of the total conductivity for air in turbulent flow were originally reported without regard to effects of viscous dissipation. The reported values were corrected for such effects by utilizing measurements taken at the time of the original investigation. The total conductivity obtained by taking into account dissipation effects was found to be independent of the average temperature gradient with which measurements were made.Part II.The heat transfer characteristics from a 0.001-inch diameterplatinum wire in the boundary flow about a 1-inch copper cylinder were measured at Reynolds numbers, based on the cylinder diameter of about 1750, 3500 and 7100. The results are presented in terms of the Nusselt number for the wire as a function of position for the three Reynolds numbers investigated. Comparison of the measured Nusselt numbers with values predicted from calculated velocity distributionsindicate that, in the vicinity of the cylinder wall, the Nusselt number is not a unique function of the Reynolds number based on the wire diameter.

[发布机构] University:California Institute of Technology;Department:Chemistry and Chemical Engineering

[关键词] Chemical Engineering