抄録
Highly subcooled flow boiling of water was performed for a horizontal circular channel with 5mm in diameter and 50mm in length of heating section. Microbubble emission boiling (MEB) occurred in the upstream section of heating surface and the heat flux increased at higher liquid velocity than 0.25m/s. The maximum heat flux was 4.5〜5MW/m^2 in the upstream section of 5〜15mm apart from the edge of the heating surface at 40K of liquid subcooling and 1.0m/s of liquid velocity. However, the local heat flux decreased gradually in the down stream section and the liquid is almost evaporated at the exit of heating section. The experimental results show that MEB is difficult to occur for longer sized heating surface than 15mm.