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Khasawneh, Khalid,Jeong, Yong Hoon Elsevier 2018 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.116 No.-
<P><B>Abstract</B></P> <P>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.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Scaling criteria developed to model high pressure steam condensation in horizontal tubes. </LI> <LI> The criteria have been validated by comparing different prototype and model pairs using three different condensation models. </LI> <LI> Main dimensionless numbers for fluid-to-fluid scaling were defined. </LI> <LI> High pressure steam condensation can be accurately simulated using Freon as the working fluid. </LI> </UL> </P>
Khasawneh, Khalid,Cho, Kun-Woo The Korean Association for Radiation Protection 2014 방사선방어학회지 Vol.39 No.2
Following the emergency work in Fukushima Daiichi nuclear power plant, more attention was paid for the radiation protection of workers working under severe accident condition. The protection procedure for the emergency workers, including the on-site emergency center, the seismic isolated building and the reestablishment of the radiation protection framework were analyzed to investigate drawbacks and deficiencies which led to adverse effects on the emergency planning and on emergency workers' health and comfort. Those drawbacks were identified and studied, and then suggestions were made to enhance the emergency working condition to avoid any future problems during severe accident emergency work and management.