Critical heat flux in flow boiling of helium

The problem of boiling heat transfer in liquid helium is of considerable importance when analysing cryostability of composite conductors applied in superconducting magnets. Experimental results on the effect of pressure, mass velocity, quality and heated length of the tube on the critical heat flux are presented in the paper. The experiments were carried out under conditions of forced helium flow in a vertical uniformly heated tube. Three typical regions of regime parameters variations were found on the basis of experimental data obtained. Critical heat flux characteristics in these three regions are different. Qualitative and quantitative analogy of critical heat flux in flow boiling of helium and high pressure water was established. Correlations for critical heat flux were developed.