Vibration-Free Cooling Cycle Pump for Space Vehicles and Habitats

Mainstream Engineering Corporation completed the design of a high-speed pump for International Space Station (ISS) Environmental Control and Life Support Systems and future spacecraft and extraterrestrial outpost applications. Specifications for this pump were derived from an existing pump currently operating as part of the thermal control loop on the ISS. The design includes magnetic bearings so that a vibration-reducing control algorithm can be implemented. A digital controller was designed, which measured and reduced vibration-causing fluctuations in shaft displacement due to rotor unbalance in multiple axes. The controller was tested over an operating speed range of 600 to 7200 rpm with excellent results. The controller reduced mean shaft displacement by 71% over the entire operating range, and reduced it by more than 80% at higher operating speeds where synchronous vibration was dominant. In Phase II the magnetic bearing equipped cooling loop pump designed in Phase I will be fabricated and tested. Mainstream will demonstrate the added efficiency, reliability, and low vibration of the system as compared with the existing pump. The pump assembly will undergo vibration characterization testing with support from Marshall Space Flight Center.