Air Cycle Toolsets for Aircraft Thermal Management System (TMS) Optimization

ABSTRACT: Modern military aircraft are encountering major thermal obstacles as a result of significant increases in on-board heat generation combined with a reduced ability to transfer heat to the ambient environment. Adaptive power and thermal management systems (APTMS) are being studied in great detail in order to mitigate these thermal restrictions, but complexity of such systems necessitates costly detailed design and controls work. On-going programs are utilizing model-based design to reduce APTMS costs and risks, but steep hardware costs ultimately restrict the number of designs that can be tested in the laboratory. An opportunity thus exists to develop complementary software and hardware toolsets, which, when co-utilized, can significantly expand the affordable design space of laboratory emulation hardware. The two key objectives of the Phase I effort are (1) the development of a software toolset with the flexibility to model a variety of air cycle machine (ACM) topologies, and (2) the conceptual design of an ACM hardware toolset capable of emulating these topologies. The software toolset will be developed in a readily-available commercial software package, while the hardware toolset will be designed for compatibility with the Air Force Research Laboratory"s (AFRL"s) test facility. BENEFIT: The ability to emulate multiple ACM architecture designs in both a modeling and laboratory environment offers several benefits to the AFRL, including: (1) reduced cost through model-based design, (2) reduced development cycle cost through hardware emulation of multiple designs, (3) optimization capability facilitated by low-cost emulation of complicated subsystem interactions, (4) rapid transition from design through prototype stages made possible by hardware-in-the-loop controls development and refinement, and (5) reduced risk in coupled subsystem development. In addition to the direct benefits to AFRL, there is a significant additional military and commercial market for the proposed toolsets. ACMs continue to be the predominate method for providing cooling air in aerospace applications. As suppliers continue to design advanced subsystems, their ability to accurately emulate an ACM on-site without transferring or developing prototype hardware will significantly reduce both cost and risk. In addition, ACM developers will benefit from reduced development time and cost through use of the model-based design and hardware emulation toolsets proposed in this effort.