Gravitational Separation in Horizontal PGV-1000 Steam Generators in Nuclear Power Plants with VVER Reactors

A method for estimating the mutual effect of moisture and purge effectiveness for PGV-1000 in nuclear power plants with VVER reactors is described. The method takes account simultaneously of the mechanism for removing impurities with moisture and in dissolved form in the steam. Experimental data are used to show that the proposed method can be used to predict the basic separation characteristics of steam generators and for choosing ways to improve the in-vessel structures. A comparison of the separation characteristics, obtained in the course of the tests, with the calculations confirms that the gravitational separation due to an increase in the height of the steam space is effective. The methods for improving the separation systems at the Volgodonsk nuclear power plant maintain a constant rate of removal of moisture in a wide range of water levels in the steam generator compared with the standard systems.[PUBLICATION ABSTRACT]