Fluid-to-fluid scaling criteria development for modeling high pressure 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 overcome those difficulties. 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 two approaches, the Buckingham Pi theorem and the non-dimensionalization of the governing equations and the interface boundary conditions. Both criteria have been validated using eight benchmark problems and based on three different condensation models. The approach based on the non-dimensionalization of the governing equations and the interface boundary conditions showed a better method for modeling the high pressure steam condensation phenomena. It showed that, in order to guarantee the similarity between the prototype and the model, the liquid-to-vapor density ratio, the Froude number and the vapor Reynolds number should be preserved. In comparison with the prototype, by applying the scaling criteria to model steam condensation in secondary system passive decay heat removal system of a pressurized water nuclear reactor, the model's pressure can be reduced by six times. Therefore, reducing the cost of conducting experimental tests.