Multichannel measuring unit for phase interface based on C/V convertor CAV444

In order to study the occurring mechanism of slug flow and the phase interface structure of it, reasonable measuring unit to measure the phase interface structure should be developed. Currently, fast valve method, attenuation sensors, gamma ray scattering, optical fibre probe, harmonic frequency of microwave cavity, nuclear magnetic resonance, et al. can be used to measure phase interface of slug flow. But all of these methods either need expensive equipment or have not versatility or measure phase distribution of local points only, the foregoing methods can not be used to measure phase interface of phase structure of slug flow under laboratory condition. Measuring the dependency relationship between the conductance or capacitance of fluid and the characteristics of phase distribution of slug flow, the phase interface and its structure of slug flow can be determined with high response speed, reasonable measurement accuracy and economic cost. Base on capacitance-voltage (C/V) convertor CAV444, a new type of measuring unit for phase interface was developed in the present paper. The principle of work of this measuring unit was given; the architecture of it was introduced in detail. The reference capacity of the developed measuring unit has great influence on its measurement property, so the relation of reference capacity to measuring range and resolving power were analyzed finally. The developed measuring has been applied in the interface position in gas-liquid two-phase flow successfully.