Material damage and thermal response of LHD divertor mock-ups by high heatflux

Mockups for tests were fabricated and thermal response and thermal fatigue lifetime tests using electron beam facilities were carried out to examine m aterial damage and thermal response of carbon carbon fiber composite (CFC) brazed the oxygen free high conductivity (OFHC) for a local island divertor (LID) plate. Model calculation for thermal response was also carried out t o explain the phenomena of experimental results. Thermal response tests of an MFC-1 mockup were performed at the condition that the water flow velocit y, pressure and temperature were 1.6-10 mis, 1.0-4.0 MPa and 20 degrees C, 150 degrees C respectively. The MFC-1 mockup showed good heat removal perfo rmance. In the case of a CX-2002U mockup with 10 mm armor thickness, surfac e temperature is near 1000 degrees C at 10 MW/m(2). Therefore, use of CX-20 02U as armor material is allowable concerning the maximum surface temperatu re due to heat flux. A thermal fatigue test of the MFC-1 mockup was also pe rformed. Temperatures increase due ro degradation was not observed up to 10 00 cycles. Calculation for thermal response was performed using a finite el ement analysis code. The comparison measured with calculated data presented information of critical heat flux and detachment of the tile. (C) 1998 Els evier Science B.V. All rights reserved.