Research on dynamicflow rate self-sensing in control valves

Abstract

In the field of control valves of nuclear energy, the measurement and control of the flow rate are widely concerned. Applying the traditional differential pressure flowmeter to directly measure the flow rate of the control valve would lead to unnecessary pressure drop, excessive energy consumption of the pump and high cost, and the obtained flow rate is mainly steady flow rate. In this paper, a self-sensing method of the dynamic flow rate of the control valve is proposed with the advantages of no flowmeter, no need to add moving parts. The original control valve in the pipeline system is used to measure the flow rate, which would not cause additional pressure and energy loss. The self-sensing model of the dynamic flow rate of the control valve is established, and the measurement of the dynamic flow rate is converted into the measurement of the dynamic pressure. The feasibility of the self-sensing model is verified by the experiment on the flow measurement experimental platform. The self-sensing performance of the dynamic flow rate under valve's various working conditions is sufficiently analyzed. Moreover, the self-sensing model is modified and optimized based on the Isight platform. The results show that by introducing the correction coefficient, the maximum relative error after optimization between the self-sensing flow rate and set value is reduced from 11% to 6% under the random movement condition of the valve plug, which enhances the self-sensing ability of the dynamic flow rate.