Molten Boron Phase-Change Thermal Energy Storage to Augment Solar Thermal Propulsion Systems

摘要

Solar thermal propulsion offers a unique combination of high thrust and high specific impulse levels that can provide competitive advantages relative to traditional satellite propulsion systems. In order to enhance the functionality of this technology, thermal storage combined with a means of thermal-to-electric conversion is suggested, with the idea of providing a dual- mode power and propulsion system based on thermal energy. A system including boron phase change material for storing energy, an insulating containment system consisting of boron nitride, carbon bonded carbon fiber, and vacuum gap insulation is proposed, with thermophotovoltaics used for electrical conversion. A laboratory solar concentration system has been constructed and experiments to directly heat small quantities of boron have begun, so that the nature and challenges of this system can be evaluated.