A POROUS METAL HEAT EXCHANGER WITH A LIQUID METAL COOLANT FOR COOLING PLASM-FACING COMPONENTS

DIVERTOR PLATES USED IN TOKAMAK FUSION DEVICES CAN BE SUBJECTED TO HEAT FLUXES OF UP TO 1 TO 5 KW/CM(2). EFFICIENT COOLING OF THESE AND OTHER PLASMA-FACING SURFACES IS NECESSARY FOR RELIABLE TOKAMAK OPERATION. THE CAPABILITY FOR POROUS METAL HEAT TRANSFER TO HANDLE HEAT FLUX AS HIGH AS 6 TO 8 KW/CM(2) HAS RECENTLY BEEN DEMONSTRATED. THESE TESTS WERE CONDUCTED USING WATER COOLANT IN A COPPER HEAT EXCHANGER. IT IS PLANNED TO EXTEND THIS TECHNOLOGY TO LIQUID METAL COOLANTS IN A HIGH-TEMPERATURE POROUS METAL HEAT EXCHANGER TO PROVIDE EFFICIENT COOLING AT HIGH TEMPERATURES AND HEAT FLUXES WITHOUT WATER COOLANT. IN PHASE I, A POROUS METAL COOLED DIVERTOR DESIGN WILL BE COMPLETED, AND A TECHNOLOGY DEMONSTRATION TEST WILL BE COMPLETED, AND A TECHNOLOGY DEMONSTRATION TEST WILL BE COMPLETED. FOR THE PHASE I TEST, NAK IS PROPOSED AS THE LIQUID METAL COOLANT BECAUSE OF EASE OF HANDLING; ALTERNATIVE COOLANTS WILL BE EVALUATED FOR USE IN PHASE II. IN PHASE II, A REPRESENTATIVE POROUS METAL COOLED DIVERTOR PLATE PROTOTYPE WILL BE DESIGNED, BUILT, AND TESTED.