High-Efficiency Heat Exchanger for Individual Stoves

TIAX, in partnership with Cascade Designs Inc. (CDI), propose to develop and deliver to the Army up to 100 high efficiency Heat Exchanger Cups (HEXC). The HEXC will achieve over 60% thermal efficiency when used with the Capillary Force Vaporizer (CFV) stove, which CDI has developed and is producing. The HEXC, in combination with the CFV stove, provides the warfighter unmatched efficiency and compactness in a JP-8 fueled stove to heat water for beverages, dehydrated rations, and hygiene. The high efficiency of the HEXC with the CFV stove gives the warfighter at least 50% more heating capacity for the same space and weight than with current cold-weather canteen cups. This means the warfighter can stay on mission 50% longer without refueling. In addition to the high performance of the HEXC with the CFV stove, the HEXC significantly improves water heating efficiency with current squad stoves. The HEXC offers this performance in a durable design that stows compactly with the CFV stove. Phase I of this project developed and demonstrated a preliminary design for the HEXC that achieved 55% thermal efficiency while maintaining low emissions. Phase II this project, proposed here, will further increase the thermal efficiency of the HEXC by optimizing its heat transfer area with a computational fluid dynamics (CFD) model validated to predict the HEXC performance on the CFV stove. Through CDI up to 100 “works-like, looks-like” HEXC prototypes will be built. These HEXC prototypes will allow the Army to field test and evaluate the HEXC.