Design and Performance Assessment of Air Cycle Machine Based Self-Contained Cooling System for Pod-Based Electronic Warfare Systems on Fighter Aircraft Platforms

Abstract Airborne electronic warfare (EW) pods installed on outboard stations require a self-contained cooling system for the thermal management of electronics. This article brings out the challenges encountered in the development of an air cycle machine-based liquid cooling system used in a pod-based EW suite on a fighter aircraft. The cooling system consists of three primary modules: ACM module, liquid circulation unit, and electronic control unit. The overall system design requirements are translated to individual module and component level performance requirements, control system modes, and health monitoring requirements. The various parameters that affect the performance of the individual component and in turn the cooling system such as inlet and outlet scoop performance, ACM performance, heat exchanger effectiveness, path losses, and pump unit are deliberated in the article and an analytical model developed to analyze and predict the performance of the system at various altitudes and Mach conditions is discussed. Finally, the experimental test results obtained during ground evaluation at a dedicated cooling system test facility and in-flight performance parameters obtained from the 2 kW air cycle machine-based liquid cooling system are discussed.