The heat-flow rate and temperature of the heater are measured at various liquid subcooling boiling points. An experimental plant and the obtained results on the heat energy motion in the superfi-cially boiling binary liquid mixtures are described. The experi-ments have used a quasi-stationary heating method which allows accurate specifying of the critical heat flux (qkr) and the tempera-ture of the heater (Th). An experimental study of the superficial boiling has determined that the critical heat flux density depends significantly on the liquid subcooling. At the liquid nucleus temperature TL=30 0С in the mixture of water-n-butanol, 10% critical heat flux reaches a considerable size of 20.68 MW/m2, and at TL=30 0С – much less qkr=2.98 MW/m2. This is due to the increase in the temperature drop (∆Т =Th kr+TL) at the moment of qkr.
superficial boiling of mixtures, critical heat flux (qkr), temperature drop (∆Т)
Введение. Значительно увеличить производство электрической энергии возможно только за счет строительства или модернизации тепловых электростанций [1]. Все тепловые электростанции работают по циклу Ренкина, где в качестве рабочего тела можно использовать только пар. Большое количество пара получают при кипении, поэтому изучение процесса кипения представляет научный и практический интерес.
При нагреве кипящей жидкости обнаруживается критическая (максимальная) плотность теплового потока qкр [2], которая соответствует максимальной скорости пара, отходящего от поверхности нагрева. Цель работы — определить величину qкр и Тст кр при различных недогревах ядра жидкости.
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