Numerical simulation of performance of traveling wave pump-turbine at different wave speeds in pumping mode

Abstract

Fish swim by flexing their bodies and energy is transferred from the fish to the water. And the plate which imitates traveling wave motion of fish can absorb the energy of fluid under certain motion parameters. By arranging the traveling wave plate in a vertical rectangular flow channel, the flow mode is changed from external flow mode to internal flow mode. This internal flow device is called traveling wave pump-turbine, and it can operate in both pumping mode and turbine mode. The traveling wave plate is simplified into a two-dimensional plate, and the model of the traveling wave pump-turbine is established. The numerical simulation method is used to study its performance characteristics at different wave speeds when it is in pumping mode. The results show that: although it operates in pumping mode by changing the volume of the working chamber, it can output stable mass flow rate. With the increase of wave speed, the volumetric efficiency increases gradually, the time-averaged efficiency first increases and then decreases, and the maximum time-averaged efficiency can reach 0.9. The instantaneous pressure and power are relatively stable when the wave speed is low, while they fluctuate more sharply with the increase of wave speed.