The performance of an evaporator tube operating under high fluxes with water is studied analytically for possible thermal conditions in the pre- and post-burriout regions. A correlation is proposed for predicting the critical heat flux under slow burnout conditions making use of the concept proposed by Mozharov that the dry-out conditions in the tube arise due to tearing of the liquid film on the periphery due to shearing action of the lighter phase flowing in the core. The correlation is found to reasonably satisfy experimental data in the Russian literature. Besides a computational procedure is employed to describe the nature of variation of both heat transfer coefficient and thermal potential (T-w-T-s) all along the length of the evaporator tube. (c) 2006 Elsevier Ltd. All rights reserved.