Performance Prediction of Turbines for Bi-directional Flow

Abstract

An alternating flow generates in the wave energy plant with an oscillating water column and in the thermo-acoustic engines. Turbines used in such devices generally rotates in a same direction. The performance of some turbines for alternating flow have been investigated by wind tunnel test and computational fluid dynamics (CFD) analysis in order to clarify their usefulness. Conventional turbines for alternating flows have some inherent disadvantages such as severe stall and low efficiency. Therefore, the authors proposed two unique turbines for bi-directional flow in recent years: Wells turbine with booster and counter-rotating impulse turbine for alternating flows. An extensive numerical works was conducted to perform a comparative study between the conventional and proposed turbines.