A CIRA 3D Ice Accretion Code for Multiple Cloud Conditions Simulations

This work presents the implementation and validation efforts of a 3D ice accretion solver for aeronautical applications, MESS3D, based on the advanced Messinger model. The solver is designed to deal with both liquid phase and ice crystal cloud conditions. In order to extend the Messinger model to 3D applications, an algorithm for the water run-back distribution on the surface was implemented, in place of an air flow stagnation line search algorithm, which is straightforward in 2D applications, but more complicated in 3D. The developed algorithm aims to distribute the run-back water in directions determined by air pressure gradients or shear forces. The data structure chosen for MESS3D allows high flexibility since it can manage the necessary input solutions on surface grids coming from both structured and unstructured solvers, regardless the number of edges per surface cells. The aim of the work is to present a validation of the model by examining the robustness of the solutions when it deals with 2D configurations and verifying the grid solution independence on 3D configurations in both liquid water droplets and ice crystals environments. The selected test cases are relative to well documented literature cases supported by experimental results from tests conducted at NASA Glenn IRT and NRCC RATFac wind tunnel.