Numerical and field experimental investigation of wind turbine dynamic de-icing process

Abstract

A two-dimensional numerical approach has been proposed in this article to help with the simulation and visualization of dynamic de-icing process, thereby facilitating a better understanding of the pertinent physical phenomena involved in the ice melting process for cold-climate wind turbines. In this method, Reynolds-averaged Navier-Stokes equations and Shear Stress Transport k-ω turbulence model are adopted to calculate the outer fluid velocity field, and a two-step apparent heat capacity method has been employed to simulate the inner phase change. Corresponding field de-icing experiments on a 2 kW wind turbine have been performed at a natural icing station to provide essential parameters and subsequent validation for the simulation. The results show that the simulations are in good consistence with experiments. The relative errors between predicted actuation durations and measured ones are in acceptable range. Through comprehensive analysis of both numerical and experimental results, the wind turbine dynamic de-icing process has been explored. It is revealed that the de-icing process of wind turbine blades is mainly consisted of four distinct periods, i.e. sharp and short temperature-rising period, plateau period, gentle and long temperature-rising period, and fluctuation period (if exists). The mechanism of the generation of each stage has also been elucidated.