Experimental study on capacitance void fraction meters for high temperature and high pressure conditions

Watanabe, Hironori; Mitsutake, Toru*; Shibata, Mitsuhiko ; Takase, Kazuyuki

The electro void fraction meter (Capacitance type meter) was applied to high temperature and high pressure condition measurement with various shapes of flow conduits such as rod bundle and pipe geometries. The principle of the meter is that the electrical capacitance of a gas liquid two phase flow changes with the void fraction. High frequency power supply enables to measure the electrical capacitance of the ion exchanged water with even though conductivity of pure water. It was confirmed by steam water boiling two phase flow experiments that void fraction can be obtained in real time way. Void fraction ranging from 0 to 0.9 at maximum was successfully measured under steam water boiling two phase flow conditions of 2 MPa through 18 MPa pressure.