Non-stationary movement in the pipeline under changing valve resistance coefficient

Changes in the characteristics of the non-stationary movement during the opening of pressure valves in pressure pipelines depend on the valve resistance coefficient, which is a variable value. As a result of the experimental data generalization for a uniformly opening flat valve, an approximation function of the local resistance coefficient over time was obtained. Considering the formula obtained for changing the valve resistance coefficient, the patterns of changing the characteristics of non-stationary movement in simple and composite tubes have been studied. The obtained regularities make it possible to obtain the value of the average velocity and pressure depending on the time during the opening of the valve.