SUMMARY

Active mobile cooling systems are required for electronics cooling and medical devices as well as microclimate cooling of individuals in protective clothing. Current mobile cooling technologies rely on passive cooling devices that lack the extended cooling durations required for these applications or are too massive to be completely mobile. The proposed study will develop a thermally activated absorption heat pump for mobile applications. The use of microchannel heat and mass transfer components could lead to a substantial reduction in the mass of mobile cooling systems. Absorption cooling technology will allow the use of waste heat or liquid fuels as a power source, greatly reducing the need for electrical power from batteries. A flexible breadboard test facility was constructed for absorption cycle analysis and component testing. Initial testing of a miniaturized ammonia/water absorption heat pump has demonstrated that cooling loads of 200-300 W are achievable in moderate ambient temperatures (20–26°C). The final phase of the proposed study will include the development and testing of a thermally activated ammonia/water absorption heat pump, fabricated by diffusion bonding multiple photo-chemically etched plates into a single assembly. This process will create every heat and mass transfer device of the overall cycle in a single joining process. It is expected that the final system will represent a fully mobile active cooling system with a cooling capacity of 300 W at elevated ambient temperatures.