The next stage in the Indian nuclear power programme envisions building 700 MWe Indian Pressurized Heavy Water Reactor (IPHWR) units. This development involves redesigning and up-rating of all the plant equipment including the reactor, steam generators (SGs), turbo-generator, major pumps, comparing to the current generation of the 540 MWe IPHWRs. The SG used is a vertical, inverted U-tube, natural-circulation type. The 700 MWe SG is of the same type, has the same tube bundle design and the same heat transfer area as the 540 MWe SG. In addition, the tube diameter, tube pitch, and outer diameter of the SG sections are the same as those for the 540 MWe SG. The geometry of the feedwater header, the flow restrictor in the downcomer, and the flow distribution plate are different in the two designs. The changes were required due to the 26% increase in steam flow rate while maintaining the same circulation ratio. This paper describes the design of the 700 MWe SG and a thermalhydraulic analysis of the SG using a one-dimensional, in-house code and a three-dimensional code called THIRST developed by AECL. The codes were validated for global parameters against the 540 MWe SG operating data. The analysis was made for two design versions, (1) with and (2) without integral preheater and for two versions of inlet primary water conditions, (1) with and (2) without primary steam at the entrance to the SG tubes. In addition, the effect of fouling and tube plugging on the long-term operation of the SG was considered. The paper covers the results obtained and discussion on the above-mentioned issues.

This content is only available via PDF.
You do not currently have access to this content.