J0601-1-6 On High Heat Cooling by Subcooled Boiling : Acceleration of MEB in Ultrasonic Field

Microbubble emission boiling, MEB has been observed in highly subcooled boiling. Liquid subcooling of 20K has been considered a threshold temperature for MEB generation under atmospheric condition. Subcooled quasi-pool boiling of binary mixture of Ethanol and water is performed with flat heating surface of 10mm in diameter in the field of ultrasonic vibration at liquid subcooling of 20K. Microbubble emission boiling is remarkably generated and the heat flux increases considerably higher than the critical heat flux as same case of highly subcooled boiling. Ultrasonic vibration is strongly effective on MEB acceleration at the threshold temperature. For the liquid with lower concentration of Ethanol, the instability of liquid-vapor interface is accelerated by Marangoni effect adding to the ultrasonic vibration.