Session: 2.1 - Recent development in CFD and Verification and Validation methods

Paper Number: 158485

158485 - Sharp Interface Term for Compressible Multiphase Flow With Surface Tension on Irregular Grids 

Abstract: 

This study presents a parallelized sharp interface VOF approach for compressible multiphase flows on unstructured grids. Emphasis is placed on accurately capturing the interplay between two fluids with a significant pressure difference, since CFD literature suggests that it has been proven difficult to stabilize the contact region with high density contrast. An interface sharpening strength parameter is analytically derived from the physical properties of the contact region, as well as the truncation error associated with the distribution of cell centers in the mesh. The relationship between (I) the magnitude of the standard deviation of the Gaussian convolution used to resolve discontinuities across the interface and (II) solution accuracy is examined. As a means of validation, the model is verified against the archetypal pressure jump (Young-Laplace) condition for a variety of initially pressurized gaseous bubbles immersed in liquid. In addition, the model is applied to simulate droplet dynamics under various Weber numbers, where pinchoff and atomization are elicited by the fluid interface. Droplet shape, size, and time of pinchoff are mapped as a function of the flow characteristics. Using tools provided by PETSc DMPlex, the model is generalized for unstructured grids, and generalized for an arbitrary distribution of parallel computer processors assigned to the domain. The proposed methods are implemented into Ablative Boundary Layers At The Exascale (ABLATE), an open-source software package being developed to simulate compressible multiphase flows.

Presenting Author: Joseph Marziale University of Buffalo, State University of New York

Presenting Author Biography: