In an effort provide significant improvements in aircraft fuel/energy economy and emissions, turbo-, hybrid, and fully electric aircraft are being developed to utilize high-efficiency electric propulsion systems (EAPs). To enable these systems, thermal management systems (TMS) are needed which can be scaled to the power ranges required while providing the efficiency and power density that makes these technologies compelling. ThermAvant Technologies, LLC proposes a novel TMS based on the company’s flagship technology: structurally embedded oscillating heat pipes (OHPs). The OHP is a passive two-phase heat transfer device that relies on concentrated heat loads to passively drive a working fluid through a high-density array of microchannels, which are ideal for embedding within thin structures such as a structural skin. Without the need for the wick structures of their conventional predecessor heat pipes, OHPs are especially well suited for integration into materials within which it is difficult to construct traditional heat pipes. In addition to the absence of a wick structure, the OHP’s unique I-beam architecture (formed by the walls between the microchannels) enables the structure to be multifunctional and serve as a structural member with integrated passive thermal management. Furthermore, through the use of additive manufacturing technology, these devices can be deeply integrated within the structure of EAP systems.
These high-conductance, embedded devices will provide significant improvements to power density by both decreasing thermal impedance and reducing mass, and provide additional design freedom for the layout of heat generating components within the EAP system while still providing improved thermal performance. To provide further performance optimization under both transient and steady-state conditions, energy storage devices will be evaluated to independently optimize the conductive and capacitive properties of the heat sink.
NASA's Electrified Aircraft Propulsion project resides within the Aeronautics Research Mission Directorate Strategic Thrust 4: Transition to Low-Carbon Propulsion. In particular, within Thrust 4, this technology has direct application to the X-57 program, as well as to the Revolutionary Vertical Lift Technology project. Beyond these applications, this technology also has application to the cooling concepts for hybrid electric aircraft that are being investigated through the HEATheR program.
ThermAvant is aware of a number of applications that could potentially use such additively manufactured, thermal devices, e.g. commercial manned/unmanned aerial vehicles, and various commercial space applications. ThermAvant believes there are a multi-million-dollar annual revenue opportunities within each of these industries if the multifunctional prototypes are able to successfully be produced.