Investigation of heat transfer characteristics of supercritical carbon dioxide at microchannels

摘要

Carbon Dioxide (SCO_2) can revolutionize the thermal management landscape due to a dramatic increase in enthalpy and a specific heat near supercritical state, particularly along the pseudocritical line, which correspond to much lower temperatures and pressures than water and other refrigerants. This study is conducted to assess the capability of supercritical CO_2 in heat transfer applications. The heat transfer coefficient of carbon dioxide near the pseudocritical conditions was experimentally studied at the micro scale. Devices with 20 micro channels were fabricated to measure local and average heat transfer coefficient as well as system pressure drop. The experimental results showed a significant increase up to 72000 W/m~2.k in local heat transfer coefficient and large pressure drop up to 3 MPa at microscale with supercritical CO_2.