Experimental Investigation of Heat Transfer Characteristics on a Gas-to-Gas Parallel Flow Microchannel Heat Exchanger

ABSTRACT

Heat transfer characteristics of a gas-to-gas parallel flow microchannel heat exchanger have been experimentally investigated. Temperatures and pressures at inlets and outlets of the heat exchanger are measured to obtain heat transfer rates and pressure drops. The heat transfer and pressure drop characteristics are discussed. The results show that experimental pressure drop is approximately ten times as large as theoretically estimated pressure drop. Geometric configuration of the heat exchanger dominates pressure drop characteristics. The conventional log-mean temperature difference method and the constant wall temperature model proposed in our earlier work are applied to predict heat transfer rate of the parallel flow microchannel heat exchanger. Prediction accuracy of the log-mean temperature difference method is superior to that of the constant wall temperature model. Applicability of the log-mean temperature difference method depends on direction of fluid flow.