Fluid-to-fluid scaling criteria development for modeling steam condensation in horizontal tubes

Abstract

Experimental investigations of high-pressure steam condensation heat transfer are limited due to technical requirements and construction costs of experimental facilities. Applying fluid-to-fluid scaling methods is a possible way to reduce those requirements and costs. It also helps to extend the current steam condensation database. Performing experiments with simulant fluid, Freon for instance, allows testing at low pressure, low temperature and with low power requirements compared with the prototype. Fluid-to-fluid scaling criteria for modeling high-pressure steam condensation have been developed based on the Buckingham Pi theorem and the non- dimensionalization of the governing equations and the interface boundary conditions. It was decided that in order to guarantee the similarity between a prototype and a model, the liquid-to-vapor density ratio, the Froude number, and the vapor-phase Reynold's number should be preserved. The scaling of the condensation heat transfer coefficient is based on the Nusselt number. The developed scaling criteria have been validated using two approaches, the first is based on condensation empirical correlations, while the second approach is based on CFD simulations. The applicability of the developed scaling criteria to allow performing experiments using refrigerants, and the use of the existent refrigerant-based databases to study high-pressure steam condensation have also been assessed.