The Maisotsenko Cycle for Electronics Cooling

Abstract

The Maisotsenko Cycle (M-Cycle) combines heat exchange and evaporative cooling [1–3] in an effective indirect evaporative cooling process resulting in product flow temperature approaching incoming air dew point (not wet bulb) temperature. Thermodynamically, the M-Cycle is based on air precooling before passing through the heat rejection water evaporating area, so the difference between the enthalpy of the air at its dew point temperature and the same air saturated at a higher temperature is used to provide cooling capacity to reject the heat, for example from the electronics. Today Delphi Corp and Coolerado Inc. are working on producing M-Cycle based heat- and mass exchangers for the Coolerado Coolers™ used in air conditioning. Other market applications, including electronics cooling, are being considered as well. A broad range of the cooling capacity (for example, from 10 W to 50 kW and more) could be obtained from the coolers utilizing M-Cycle. Due to superior thermodynamic process, M-Cycle based air coolers have a very high Energy Efficiency Ratio (EER). As per National Renewable Energy Laboratory (NREL), the average cooling capacity of Coolerado Coolers™ have EER more than 45; relatively to EER equal 13 for the best conventional air coolers. The M-cycle is much more efficient than any other heat rejection/recovery cycle, and the Coolerado Cooler™, as a single air cooling device has better specific characteristics (cooling capacity, air pressure drop, power consumption, etc.) than any existing coolers. Unlike traditional vapor compression, absorption, or thermoelectric refrigeration systems, where increase of air inlet temperature dramatically reduces cooling capacity, the M-Cycle based unit cooling capacity goes up with air inlet temperature rise. M-cycle based device similar to Coolerado Cooler™ can also cool any fluid to the temperature approaching the dew point temperature of incoming air without using compressor and refrigerant. That can revolutionize the electronics cooling market. The Coolerado Cooler was recognized by the prestigious R&D 100 Awards program as one of 2004’s most technologically significant products introduced to the world.