The conversion of energy in a radiator
A 1938 NASA technical report on the thermodynamics of energy conversion in a radiator, written for aeronautical engineers and researchers. The pictures are technical line graphs of pressure against speed on Fanno and adiabatic curves, a chart of curves labelled by parameter values, and drawings of a cold radiator with and without a nozzle plus a view of tubed fin-and-tube matrix with arrows showing airflow, giving a designer clean diagrammatic forms for schematic line work.
