Modeling and Analysis Thin Wall Film Formation with Integrated Discrete and Continuous Phase Simulation Approach

Abstract

Water film will be initiated and formed under the continuous impingement of incoming supercooled droplets, and directly affect the ice formation, which is always vital for the performance and safety of aero-engine. A hybrid algorithm integrating Discrete Phase Model (DPM) and Volume of Fluid (VOF) was established to simulate all the stages from droplet initiation to the film well-formed which can make the numerical simulation of icing more realistic and accurate. The transformation criterion from the particle to liquid volume fraction and the distribution of source terms has been improved compared with similar previous approaches. Three verification cases, namely single droplet train impact, staggered droplets impact and two glycerine-solution droplet impact, were conducted to verify the mass conservation and the applicability to both the sparse and dense two-phase flow. The results showed that the relative error of mass transformation is no more than 0.5%. The comparison between simulation and experiment result demonstrated that the hybrid algorithm has the ability to simulate the flow behaviour of droplets accurately. The thin water film formation on a typical wing of NACA0012 airfoil was then analysed, the results of which illustrated that the integrated algorithm could successfully capture the characteristics of liquid film formation and motion.

Marking function of Stokes number on airfoils’ aerodynamic penalties in a gas–solid flow

“…Later, a multiphase CFD model based on the coupled Lagrangian–Eulerian approach was developed to capture the water‐film formation over the S809 airfoil, and it was found that heavy rain could result in a significant performance loss [6, 7]. Recently, this model was also employed to simulate the process of icing [15].…”

“…Later, a multiphase CFD model based on the coupled Lagrangian-Eulerian approach was developed to capture the water-film formation over the S809 airfoil, and it was found that heavy rain could result in a significant performance loss [6,7]. Recently, this model was also employed to simulate the process of icing [15]. The research by Guo et al [10] indicated that compared to the airplane airfoils, wind turbine airfoils have highly sensitive angles in the operating range and a larger effect of particles could be obtained through momentum exchange between air and particles.…”