Dimensional Analysis, Modeling, and Experimental Validation of an Aircraft Fuel Thermal Management System

Experiments are designed and executed to test the validity of theoretically derived dynamical system models of two configurations of an aircraft fuel thermal management system. Dimensional analysis is used to design a small-scale experiment that achieves dynamic similitude with a notional full-scale aircraft. It is shown that dynamic similitude can be achieved by using small-scale heat exchangers and pumps with water as a surrogate for jet fuel. Similitude is accomplished by matching several nondimensional parameters between the full-scale model and the subscale experiments. It was found that, in order to obtain agreement, it was necessary to modify the original theoretical model to include the heat transfer effects among the water, tank walls, and ambient environment. It is shown that when the subscale experimental results and full-scale simulation results are nondimensionalized, agreement is obtained. Furthermore, this experiment confirms a theoretical prediction from previous work, namely, that thermal endurance of a dual-tank fuel flow topology exceeds that of a single-tank topology for equivalent initial fuel load, flow rates, and flight conditions.