1992 年 12 巻 1Supplement 号 p. 115-118
To improve the accuracy of BWR safety evaluation, it is necessary to measure void distributions in high-pressure steam-water two-phase flow. For this purpose, the authors have developed a new technique using a high-speed rotating disc for X-ray beam scanning. Using the disc scanner, void distributions were measured across a pipe cross-section every 2.5 ms under various conditions. The device can visualize the transient flow pattern on a color CRT in real time. Using the measured flow pattern, a new flow-pattern map was made for high-pressure steam-water two-phase flow in a horizontal pipe. Results were compared with a flow pattern map used in the TRAC code. The measured flow patterns are about the same as those of the TRAC code. There seems to be little pressure effect on the flow pattern borders as pressure changes from.5 MPa to 7 MPa.