A finite-element model of a microchannel CO, evaporator is presented. The overall modeling strategy appears sound based on favorable qualitative trends in calculated temperature and heat flux distributions within the evaporator. Calculations of the volumetric cooling capacity of the evaporator also follow expected physical trends. That is, refrigerant-side heat transfer coefficient (h{sub}r) has a negligible effect on volumetric capacity and air-side heat transfer coefficient (h{sub}a)-a thermal resistance two orders of magnitude larger-has a large impact, with capacity increasing almost directly as h{sub}a. Validation with experimental data was also attempted, although a direct comparison could not be made since the value of h{sub}a for the data is not known. These capacity values can be looked upon as a representing the most optimistic results for the given situation; they constitute an estimate of the performance limitations of this particular evaporator geometry for given values of air and refrigerant-side heat transfer coefficients. Pressure drop and dry-out in the evaporator may be expected to produce lower capacity values in an actual device.
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