Ferrofluidic Thermal Switch

ABSTRACT: To address the Air Force need for a thermal switching device to provide temperature control of DoD system components for improved thermal management, Physical Optics Corporation (POC) proposes to develop a new Ferrofluidic Thermal Switch (FTS). The proposed device is based on the novel dual use of a ferrofluid as a temperature conductive medium and magnetic actuation to control the position of the ferrofluid inside the thermal switch. The new system design and use of ferrofluid as a medium with high-thermal conductivity allow implementation of heat flow switches with a high switching ratio of 10 to 100. A novel magnetic actuation mechanism allows implementation of fast, low-power switching and reduction or total elimination of the number of moving mechanical components, which will increase the reliability and the lifetime of the FTS system. In Phase I, POC will demonstrate the feasibility of our FTS system by developing a system design, extensive modeling, and building and testing a proof-of-concept prototype. In Phase II, POC plans to develop two functional prototypes of the FTS system, demonstrate the system"s capability to function in the temperature range of -60 degrees C to +100 degrees C, and work with heat fluxes of 10 to 100 W/cm^2. BENEFIT: The POC FTS system will provide the Air Force with a modular, active, in-flight, configurable thermal switching device that will allow accurate control of thermally sensitive devices onboard spacecraft and satellites. Thermal switches have a potential to dramatically reduce the amount of analysis and testing required for the development of spacecraft, reduce the mass of the system, and provide a modular solution for heat control. The FTS device can also be incorporated by the Air Force into the thermal control systems of aircraft, which will benefit from the ability of the FTS system to control and modulate the heat flux from the critical temperature-sensitive components. The proposed FTS system will find direct application in a range of commercial applications that require accurate heat flow control. Such applications include thermal control of sensitive aircraft and ground vehicle components. The FTS system can also be used to provide better thermal control for structures and buildings to optimize energy consumption and heat regulation.