TITLE : ANALYSIS OF TEMPERATURE AND FLOW IN DAMAGED AGR FUEL STRINGERS USING THE COOLFUEL 3-D CODE

BY : NNC Ltd. - R P Hornby, M-T R Fung and L S L Yu
FOR : Nuclear Electric plc.

DETAILS :

• Three-Dimensional steady or transient flow with heat transfer
• Buoyancy-free or buoyancy-influenced flow
• Damaged fuel in the fluid domain represented using porosity with a separate solver for temperature
• Surface to surface radiation included

NOTES :

• A thermal assessment of damaged fuel is required to support analysis of the low probability fault of an AGR fuel stringer being dropped during refuelling
• Adequate cooling by conduction, convection and radiation heat transfer can be demonstrated

The pictures are as follows:

1. Typical flow and temperatures for a zigzag type fuel damage configuration 2. Temperature profiles along a vertical stack of damaged fuel elements. The peak in the pin bundle temperatures is due to the presence of overlapped pin bundles (larger resistance to flow, increased heat generation per unit length) 3. Temperature profiles along the stack with the overlap region occurring at a lower axial location

More details about the study may be found in :- A Generalised PHOENICS Model for the Prediction of Damaged Fuel Pin Temperatures in Advanced Gas Cooled Reactors PHOENICS Journal, Vol. 6, No. 1, pp 1-55, 1993

For information about COOLFUEL 3-D or CFD at NNC please contact :- Dr Bob Hornby NNC Ltd. Tel : 0565 - 633800 x 3912 Fax : 0925 - 633659

Typical flow and temperatures for a zigzag type fuel damage configuration
Temperature profiles along a vertical stack of damaged fuel elements
Temperature profiles along the stack with the overlap region occurring a lower axial location