Rapidly Configurable Turbomachines for Air Cycle Machine Emulation

ABSTRACT:An air cycle machine (ACM), typically used in airborne thermal management systems, consists of a power turbine that utilizes high pressure bleed air, along with a cooling turbine to produce the necessary shaft power for a compressor and starter/generator. A system that sufficiently simulates actual ACM functionality and dynamics in laboratory environment is sought to minimize aircraft development costs and schedule risks. In Phase I, Mainstream successfully completed the initial phase for developing an air-cycle machine (ACM) emulator. The original Phase I feasibility effort consisted of designing the ACM components as well as fabricating and experimentally validating one such component (i.e. cooling turbine rotor). In addition, Mainstream delivered and integrated the cooling turbine, along with a load-dissipating turbocharger compressor, in an Air Force Research Laboratory test facility and demonstrated the cooling turbine capability. In Phase II, Mainstream will continue the development of the laboratory emulators and will deliver two sets of matched turbine/compressor configurations for installation, testing, and evaluation during the period of performance.BENEFIT:The proposed approach seeks to emulate the cooling turbine and compressor of an air cycle machine to test various configurations of an aircraft thermal management system in a laboratory environment. By developing a laboratory based ACM designed to be easily and rapidly converted from one configuration to another by interchanging turbine rotors and compressor impellers, the technology enables testing of various cooling TMS configurations at relatively low cost when compared to actual airborne ACM. While the compressor technology for this program is developed for a larger application, the compressor can be scaled down and operate as an electrically driven supercharger for automobile applications. By being an electrically driven supercharger, fuel efficiency can be increased by minimizing turbo-lag present in traditional turbochargers. There is a very large commercial potential for the proposed system. The market size for automotive turbochargers/superchargers is large and growingthe global market size was approximately $1.9B in 2010 and is expected to grow to $2.9B by 2015.