A robust coupling algorithm applied to thermal ice protection system unsteady modeling

Abstract

The aim of the present paper is to propose a general methodology for the numerical modelling of both anti and de-icing systems. A lubrication model is used for dealing with the dynamics of the runback water film. As regards thermal effects, in order to take into account heat conduction and unsteadiness, a parabolic temperature profile is assumed with respect to the normal coordinate for the ice layer. Heat transfers in the airfoil solid structure are described using a dedicated solver based on the unsteady heat conduction equation. The most original contribution of this work is the new technique (herein referred to as the "improved Schwarz method") which is proposed for coupling in a robust way the accretion-runback model and the solid heat conduction model. This new coupling algorithm allows to ensure fast convergence of both temperature and heat flux at the coupling interface (airfoil outer surface) and can be used either for steady state computations (anti-icing mode) or unsteady computations (de-icing mode). Numerical test cases which have been performed so far are very promising and show the relevance of this new approach for real applications and 3D extension.

An implicit time marching Galerkin method for the simulation of icing phenomena with a triple layer model

“…With these results at hand, the next step is to couple this methodology with a solver for an electrothermal ice protection system [8]. Moreover, combining them with recent work on ice shedding mechanisms [5,4] would enable the simulation of a full de-icing cycle.…”

Study on Loose-Coupling Methods for Aircraft Thermal Anti-Icing System

“…where T ref is the freezing point temperature, 273.15 K. When dry air flows through wet surface, diffusion process of water molecules occurs under the concentration difference, and the evaporative water flow can be obtained by the Chilton-Colburn analogy theory [23]:…”

“…Then, the temperature solved by the thermodynamic model of the runback water is converted to a Robin boundary condition for the temperature update in the solid domain. By adopting the "improved Schwarz method," Chauvin [23] took the same Fourier type boundary condition at the interface for both internal and external heat transfer calculations, and the surface heat flux was updated by its relationship with the temperature difference between the two adjacent domains. CANICE [19], Zhou [24] and Mu [25] directly used the surface heat flow from the solid heat conduction to solve the runback water equations, and the obtained temperature was taken as a Dirichlet boundary condition for the solid skin to update the interface heat flow.…”

A mixed adhesion–brittle fracture model and its application to the numerical study of ice shedding mechanisms

“…Icing codes typically include several modules in order to determine water droplet catch efficiency, ice growth and heat and mass transfer. A full electrothermal de-icing numerical simulation requires going through all of these steps and adding a shedding criterion [9,38,10,43,39]. But this whole panel of modules shall not be used here.…”