Assessment of Heat Exchanger Degradation in a Boeing 737-800 Environmental Control System

Abstract There are a number of systems on an aircraft working together, in harmony, to produce safe and trouble free flight. The environmental control system (ECS) is one these systems, its failure major contributor unscheduled maintenance, particularly older aircraft. ECS composed several complex sub-systems components, but at heart the passenger air conditioner (PACK). PACK prone degradation, which can lead functional ECS. Often degradation masked by overall this can, ultimately, result shutting down extensive maintenance being required. critical fault modes associated with PACK, paper, those primary secondary heat exchangers (SHX) explored. A robust simulation framework called Simscape under all conditions (SESAC) has previously been implemented, calibrated, tested against data from healthy systems. Here simulations extended cover degraded components representative Boeing 737-800 model. Fault such as blockage fouling assessed for PACK. Simulation results, terms temperature, pressure, mass flow various severities, presented discussed. results highlight interdependency between strong association performance. reported methodology findings serve further step towards goal formulating cost-effective isolation diagnostic solution.