A simple field function for solving complex and dynamic fluid-solid system on Cartesian grid

TL;DR

This paper introduces a simple, efficient field function for solving complex, dynamic fluid-solid systems on Cartesian grids, improving interface tracking, collision detection, and force integration.

Contribution

A novel field function that explicitly tracks subdomains and interfaces, enabling low-memory, efficient simulation of complex fluid-solid interactions on Cartesian grids.

Findings

Effective interface tracking in fluid-solid systems

Enhanced collision detection and force computation

Validated with subsonic to supersonic flow simulations

Abstract

In this paper, a simple field function is presented for facilitating the solution of complex and dynamic fluid-solid systems on Cartesian grids with interface-resolved fluid-fluid, fluid-solid, and solid-solid interactions. For a Cartesian-grid-discretized computational domain segmented by a set of solid bodies, this field function explicitly tracks each subdomain with multiple resolved interfacial node layers. As a result, the presented field function enables low-memory-cost multidomain node mapping, efficient node remapping, fast collision detection, and expedient surface force integration. Implementation algorithms for the field function and its described functionalities are also presented. Equipped with a deterministic multibody collision model, numerical experiments involving fluid-solid systems with flow conditions ranging from subsonic to supersonic states are conducted to validate and illustrate the applicability of the proposed field function.