Study and analysis based on flow characteristic tests of control valves

In order to consolidate the theoretical foundation of the control technology research of terminal equipment of air conditioning chilled water systems, according to the provisions of GB/T 50155-2015 and GB/T 30832-2014, performs the ideal flow characteristic and working flow characteristic experiments for an electric two-way control valve prototype with equal percentage flow characteristic. Based on the measured relative flow rate and relative trip data of the prototype, obtains the ideal flow characteristic and working flow characteristic curves. The experimental results show that the ideal flow characteristic curve of the prototype presents an approximate S-shaped characteristic, which is far away from the equal percentage flow characteristic. Both the ideal flow characteristic and the working flow characteristic have two characteristic curves that do not completely overlap for the positive and negative stroke of the control valve. Questions the theoretical basis of using the control valve to compensate the nonlinear heat transfer characteristic of the surface heat exchanger.