A New Small-Scale Method for Measuring Fuel Thermal Stability 650114
A miniature single-tube heat exchanger has been set up for making precise measurements of the fuel-side, heat-transfer coefficient. Conditions of turbulent flow, temperature level, and heat flux are maintained to simulate high Mach number flight. The decay of the fuel-side coefficient, due to the deposition of a varnish film at high temperature, is measured over extended time intervals. The rate of decay of the coefficient as a function of temperature is a quantitative measurement of fuel thermal stability. The device has been named Minex.