NATIONAL AERONAUTICS AND SPACE ADMIN LANGLEY RESEARCH CENTER HAMPTON VA
Simple curves are presented by which the basic pressure-drop characteristics of unheated tubular radiators can be corrected to operating conditions in which the radiator is heated and in which the Mach number of the tube flow is of appreciable magnitude. The only data required for the use of the curves are the radiator dimensions, the rate of heat input, the pressure and temperature ahead of the radiator, and the rate of mass flow of air through the radiator. The accuracy of the curves for predicting the compressibility effects for unheated radiators is confirmed by comparison with test data obtained from two independent sources. An example of the use of the curves for a typical oil-cooler installation is given.