Experimental research of critical heat flux under uniform heating and circumferential nonuniform heating in vertical circular channel

In this paper, the critical heat flux (CHF) experiment in uniform heated and circumferential nonuniform heated vertical channels is developed for the sub-critical energy blanket in the fission-fusion hybrid energy system. The experiment forecast correlation, based on the critical heat flux experiment in the the uniform heated vertical channel, is obtained. The accuracy and reliability of these experiment correlations are proved by statistics analysis and comparison with the present correlations. Based on this experiment correlation, the effect of the circumferential nonuniform heating on the critical heat flux is compared. The experiment result shows that the effect of the mass flux on CHF in nonuniform heated condition is less than that in the uniform heated condition. The CHF of nonuniform channel is lower than that of the uniform channel while the quality is low, otherwise, is higher than that in the uniform channel while the quality is high. The rate of CHF in the nonuniform channel and the uniform channel is nearly linear with the quality. (authors)