POWER CALCULATION OF STRAIGHT-PIPE STEAM GENERATOR WITH SODIUM COOLANT

Abstract

The article investigates the influence of coolant flow profile nonlinearity through straight-pipe steam generators tube assembly for fast neutron reactor with sodium coolant on heat exchanger power. When designing steam generators, a very important task is to correctly calculate the output parameters of the steam generator, especially the power. For the plants without reference solutions it is necessary to perform a deep analysis of the factors affecting on calculated parameters and to incorporate these parameters in the codes. An example of a new plant that do not have analogues is a shell-type steam generator for perspective fast neutron plants with liquid metal sodium coolant. The application of new solutions in steam generators design requires experimental and calculational justification of thermal hydraulic with the use of modern calculation codes. Power calculation of steam generator is carried out by thermohydraulic code “KORSAR/GP”, “PGN-2K”. One of the assumptions in coolant path parameters calculation model (tube space) is a uniform velocity profile by cross-section of tube assembly. It’s also accepted, that each heat exchange tube has the same expense of feed water. On the other hand calculational CFD and experimental studies at aerodynamic model of steam generator showed the presence of significant unevenness of coolant expense by tube space cross-section which is not taken into account in thermohydraulic calculations. The article contains the methodic of accounting for the known uneven coolant flow profile by tube space cross-section in liquid metal steam generator calculation. Based on the results obtained, measures to improve power output and reliability are proposed.