Abstract:
The theoretical models of critical film thickness andminimum wetting rate were established for locally heated and subcooledlaminar films under different flow directions of gas and liquid, and theeffects of the contact angle, film temperature, interfacial shear and heatflux were discussed driving by gravity or/and interfacial shear. Theinvestigation shows that the critical film thickness and minimum wettingrate increase with increasing heat flux. The effect of contact angle isclearly different in different range of heat flux under gravity driving, andthe film temperature has a contrary influence on minimum wetting ratedriving by gravity and interfacial shear. The critical film thickness andminimum wetting rate decrease with cocurrent shear. Under the combination ofgravity and interfacial shear, the effect of cocurrent shear on minimumwetting rate is closely related with the ratio of gravity to shear, and theincreasing countercurrent shear leads the critical film thickness andminimum wetting rate to decrease.