Molten Boron Phase-Change Thermal Energy Storage: Containment and Applicability to Microsatellites (Draft)
Abstract
Latent heat thermal energy storage systems promise nearly constant temperature operation and greater energy storage densities than sensible heat energy storage systems, but they are not yet commonly used in practice due to limitations in material degradation and heat transfer rates. Systems employing particular elemental materials with high melting temperatures appear to overcome these limitations, yielding significant performance increases, particularly in bimodal (thermal and electric) solar thermal power systems. A review of candidate materials has concluded that silicon is an excellent candidate for near term, moderate performance systems, while boron, the primary focus of this paper, is an excellent candidate material for future high-temperature, high performance systems suitable for advanced microsatellite solar thermal propulsion and power systems. General considerations for systems employing such materials have been identified, the required support technologies, including high temperature thermal insulation and thermal to electric power conversion, have been evaluated, and a preliminary design for a general system has been completed. Several potential applications have been identified for this technology; one of them, a solar thermal power and propulsion unit for a 100kg microsatellite, will be described in this paper. The preliminary analysis indicates that such a bimodal system would enable large delta V maneuvers for 100kg microsatellites while also producing the required electrical power. A solar thermal test facility for further evaluating such systems is described along with initial results from the build-up phase of the facility.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2011
- Accession Number
- ADA546871
Entities
People
- Anthony P. Pancotti
- David B. Scharfe
- Marcus P. Young
- Matthew R. Gilpin
Organizations
- Air Force Research Laboratory