Critical heat flux in vertical steam-generating channels in the absence of circulation of heat-transfer agent: Critical power of channels of different shapes

An experimental investigation is performed of the critical heat flux in vertical channels in the absence of circulation of heat-transfer agent through the lower cross section. Experiments are performed in tubes $30$, $40$, and $80$ mm in diameter, as well as in $19$- and $40$-rod assemblies. Equations are suggested for the calculation of critical power, which are valid in a wide range of the geometric and process parameters, including at a low pressure.