Study of Wake Characteristics of a Horizontal-Axis Wind Turbine within Two-Phase Flow

Abstract

The two-phase flow is addressed for the more accurate estimation of the wake characteristic for the horizontal-axis wind turbine operating in the complexly unsteady environmental states. The computational fluid dynamics (CFD) method is implemented for performing the three-dimensional wind turbine using the simulating software tool of FLUNT. Three types of environmental states, single-phase flow, liquid-gas flow and solid-gas flow, are performed for the comparison of velocity and pressure distribution to derive the specify feature for wind turbine within two-phase flow environmental state. The calculated results shows that there has the similar evolutional tendency of velocity distribution for both single- and two-phase flows and the velocity decrement at the distance of 20 meter away from wind turbine still reach to 80% of inflow speed. But the turbine blade within two-phase flow is subject to the unsteady flow with the larger velocity gradient compared with that within single-phase flow. For the static pressure, large difference occurred in these three types of environmental state reveals that the second material in addition to atmospheres causes the prominent influence of aerodynamic force and its power coefficient. The results exhibit that wind turbine within solid-gas flow has the largest power coefficient that those within the gas and liquid-gas flows.