Hydraulic characteristics of the Parshall flume entrance wingwall: Numerical simulation and test

Abstract

AbstractThe Parshall flume is a common open channel water‐measuring facility that is widely used in hydrological monitoring, agricultural irrigation and municipal water supply. In engineering applications, there is no clear requirement for the form of the wingwalls connecting the channel and Parshall flume. Therefore, it has different effects on flow measurement accuracy, flow velocity distribution and hydraulic characteristics. To standardize its construction requirements, a wingwall form with high flow measurement accuracy is evaluated. Computational fluid dynamics (CFD) numerical simulations and hydraulic experiments have shown the influence of different wingwalls on hydraulic characteristics. The governing test parameters include wingwall forms, incoming flow and degree of submergence. By measuring water surface fluctuation, streamline distribution and flow measurement error, the effects of different wingwall forms on flow measurement accuracy and hydraulic characteristics were evaluated. The results showed that the fluctuation of the water surface is affected by the boundary conditions. Layout I has the highest flow measurement accuracy and has an arc‐shaped wingwall with a radius of 1.5 m. By comparing the results of the tests and simulations, the average error is 3%. The results showed that the hydrodynamic model of the Parshall flume can provide a theoretical basis for the design and development of the measurement structure in the future.