Experimental Investigation of Critical Heat Flux

Experimental studies were performed to determine the critical heat flux (CHF) during steady state flow boiling on zirconium cladding material. Experiments were conducted in a vertical, internally heated, concentric-annulus test section composed of a glass tube containing zirconium tube with outer diameter of 9.14 (mm) and the length of 365 mm. The inlet parameters were set in the ranges of pressure from 120 to 400 (kPa) in pair with the inlet temperatures from 64 to 103 (°C) and the mass flux ranged from 400 to 800 kg/m
²
s. During the multiple occurrences of the CHF a thin layer arose on the heated tube surface by time leading to creation of super-hydrophilic surface. The experiments were therefore divided into two sets of results based on the time spent in the test section. The total number of 69 experimental runs were collected.