Void fraction measurement of the air-water two-phase flow in the sub-channel of a rod bundle geometry based on an impedance meter

The research of two-phase flow is very important for the safe operation of nuclear reactor. However, measurement method is a limitation for the experiment investigation of the two-phase flow in rod bundle channel. To measure the average void fraction of a sub-channel in rod bundle geometry, a new impedance meter is developed. The sensor of the impedance meter is composed of twelve electrodes. Due to the special architecture of rod bundle channel, the sensitivity and linearity of the impedance meter are different for different combination schemes of electrodes. To find the best scheme for the impedance meter, some combination schemes are researched based on the distribution of electric field. Simulation and experiment methods are used to study the schemes. A best scheme is given at last, and an experiment is designed to prove the result.