National Aeronautics and Space Administration

Glenn Research CenterGlenn Research Center


The Thermal Energy Conversion Branch is responsible for planning, conducting and directing research and development to advance the state-of-the- art in a variety of thermal energy conversion systems for aerospace, as well as non-aerospace applications. The branch provides subject matter expertise in thermodynamic heat engines, heat source integration, and waste heat rejection for radioisotope, fission, and solar thermal power system applications from basic research principles to integrated flight systems.

Specific focus areas include Stirling and Brayton power conversion engines, fluidic heat transfer systems, heat exchangers, gas bearings, linear and rotary alternators, engine controllers, heat pipes, and thermal radiators. Energy conversion technology maturation is pursued through conceptual design, computational tool development, parametric system modeling, and a broad range of experimental testing. Interdisciplinary analysis is performed to resolve mechanical, electrical, fluid, and heat transfer performance across the integrated energy conversion system.

A primary area of emphasis is the performance verification testing of components and systems in a relevant environment in order to validate design methods and analytical predictions. Laboratory testing is conducted in both air and thermal/vacuum to characterize energy conversion performance, life, and reliability.

The overall effort is performed through a combination of coordinated contracts, grants, and in-house activities. Elements are often performed in direct support of specific projects and customers. These customers may be from within GRC, at other centers within the agency, outside the agency but within Government, or from the U.S. aerospace industry. When possible, collaborative and cooperative efforts are formulated to leverage the resources of the project.

Currently, the branch supports programs/projects from NASA’s Science Mission Directorate (SMD) for the Advanced Stirling Radioisotope Generator (ASRG) [.pdf], Technology Advancement and Extreme Environments, as well as NASA’s Human Exploration and Operations Mission Directorate (HEOMD) for the Nuclear Systems Project (NSP).