A Two-Phase Mechanically Pumped Fluid Loop for Thermal Control of Deep Space Science Missions


NASA’s planetary science objectives are achieved through mission opportunities and the ability to obtain quality science data. Toward this end, a flight system that requires fewer resources in extreme environments while providing the stability for maximum instrument return is a fundamental goal of the engineering team. Thermal-related challenges represent some of the largest threats toward this goal. These include the ability to deal with disturbances from widely varying environments while allowing for cost-reduction options that include non-nuclear power systems and smaller spacecraft. Such options are enabled through heater power conservation and higher heat flux management, respectively. A thermal management system that can concurrently provide a precision temperature-controlled platform for instruments would further lower instrument noise floors, allowing for better science data return.

A two-phase mechanically pumped fluid loop (2-φ MPFL) thermal management system addresses these needs. A reference mission was developed to illustrate savings associated with such an architecture in terms of system resources, while maximizing the range of planetary science consistent with the Planetary Science Decadal Survey. Thermal/fluid architecture and system configuration tradeoffs highlighted key component and system sensitivities and critical environmental drivers. Results from the corresponding flight system model highlight the benefits of a 2-φ MPFL, such as efficient waste heat reclamation to address the precarious energy balance associated with deep-space, solar-powered missions. The specific loop architecture was derived based on a set of underlying performance requirements and included the development of a system thermal-hydraulic/thermodynamic model for performance trade studies, including working fluid selection. It was determined that a key component of the loop, which influenced the overall architecture, was the heat-acquiring and isothermalizing evaporator. Results from this specific study are also presented, which include early test data on a subscale prototype. Finally, a path forward highlighting 2-φ MPFL challenges and system recommendations is presented.


United States
Jet Propulsion Laboratory
Tohoku University
Polytechnic University of Turin
University of California, Berkeley
ICES201: Two-Phase Thermal Control Technology
Vienna, Austria
Eric Sunada, Jet Propulsion Laboratory/California Institute of Technology, USA
Benjamin Furst, Jet Propulsion Laboratory/California Institute of Technology, USA
Pradeep Bhandari, Jet Propulsion Laboratory/California Institute of Technology, USA
Terry Hendricks, Jet Propulsion Laboratory/California Institute of Technology, USA
Joshua Kempenaar, Jet Propulsion Laboratory/California Institute of Technology, USA
Brian Carroll, Jet Propulsion Laboratory/California Institute of Technology, USA
Gajanana C. Birur, Jet Propulsion Laboratory/California Institute of Technology, USA
Hiroki Nagai, Tohoku University, Japan
Takurou Daimaru, Tohoku University, Japan
Kenichi Sakamoto, Tohoku University, Japan
Stefano Cappucci, Politecnico di Torino, Italy
Jordan Mizerak, University of California, USA
The 46th International Conference on Environmental Systems was held in Vienna, Austria, USA on 10 July 2016 through 14 July 2016.


Two-phase thermal control, Mechanically Pumped Fluid Loop, Thermal control for Deep Space Science Missions, Waste heat reclamation, Isothermal evaporator, Large-area evaporator, Two-phase working fluid