High Performance Fuel Design for Next Generation PWRs: 11th Quarterly Report

Quarterly Report for Project DE-FG03-01SF22329 April 2004 – June 2004I. Technical Narrative: The overall objective of this NERI project is to examine the potential for a high performance advanced fuel for Pressurized Water Reactors (PWRs), which would accommodate a substantial increase of core power density while simultaneously providing larger thermal margins than current PWRs. This advanced fuel will have an annular geometry that allows internal and external coolant flow and heat removal. The project is led by the Massachusetts Institute of Technology (MIT), with collaboration of four industrial partners – Gamma Engineering Corporation, Westinghouse Electric Corporation, Framatome ANP (formerly Duke Engineering & Services), and Atomic Energy of Canada Limited

High Performance Fuel Design for Next Generation PWRs Appendices B-I to FY-02 Annual Report

Progress Report for Work August 2001 through July 2002B.1.1 VIPRE modeling of PWR core with annular fuel: Optimization studies in the first year used an isolated channel and models for MDNBR analyses. These analyses provided sufficient knowledge of potential thermal hydraulic performance of annular fuels to select the 13x13 array as the most promising configuration. To obtain more realistic and accurate MDNBR, a whole core model is necessary. In particular, the major concern is correct representation of channel flow rate. The earlier models used the core-average mass flux, which does not account for flow rate reduction in the hot channels due to increased pressure drop in this channel as a result of higher subcooled, or possibly, saturated boiling. Therefore, it is expected that the MDNBR obtained from the full core VIPRE-01 model will be smaller than the values obtained from the isolated channel model