THERMO-FLUID ANALYSIS OF TWO-PHASE FLOW WITH PHASE-CHANGE AGAINST INTENSE HEAT IN POROUS MEDIA

摘要

A new cooling system using sintered porous media has been proposed to remove high heat flux on plasma facing components in a fusion reactor. By using this system, it is possible to remove the heat flux of several MW/m~2 with high thermal efficiency. It is difficult, however, to elucidate the thermo-fluid mechanism in the porous media experimentally because of its complicated internal structure. For this reason, the present study aims to carry out the thermo-fluid analysis of two-phase flow with phase-change in the porous media, and to elucidate its fundamental flow characteristics under the heat flux mainly of O (0.1) MW/m~2. As a result, in the case that the porous material has lower thermal conductivity, the heat transport by latent heat of vaporization is dominant, but the thermal penetration toward single-phase region behind the two-phase region is a little. On the other hand, in the case of higher thermal conductivity material, the heat transport by sensible heat in the single-phase region as well as by the latent heat in the two-phase region works effectively. As to the heat removal over 10 MW/m~2, it is clarified that the increase of inlet velocity and higher thermal conductivity of porous media could be necessary.