TECHNOLOGY OF MICROCHANNEL EVAPORATIVE THERMOREGULATION

This study is devoted to experimental and theoretical analysis of application of flow boiling heat transfer phenomenon for thermal control issues. The authors present an experimental research of heat transfer and critical heat flux (CHF) for subcooled flow boiling of ethanol in microchannel heat exchanger consisting of 28 rectangular channels with hydraulic diameter of 0.5 mm. Investigation was completed for ethanol velocities range of 0.5-1 m/s and inlet temperatures 48, 58 and 68 oC. The onset of the critical heat flux is directly related to the hydraulic instabilities which result in the emission of vapor into the inlet manifold. Subcooling of the fluid significantly effects the value of CHF, especially at high flow rates.