Our computational fluid dynamics research includes both density and pressure-based algorithm development for chemically reacting, multi-phase, multi-species, compressible and incompressible, steady and unsteady, subsonic, supersonic, and hypersonic flows. The applications areas include combustion processes, turbomachinery, turbulence modeling for steady and unsteady flows, heat transfer and drag computations for flow over smooth or rough surfaces, conjugate heat transfer, flow around moving/separating bodies, pollutant transport, coal gasification system, and biomedical fluid flows. Several research efforts are underway: a unified environment for continuum to atomic scale simulations utilizing Reynolds Averaged Navier-Stokes (RANS) equations and Direct Simulation Monte-Carlo (DSMC) approach; six degree of freedom (6DOF) libraries; spray combustion instability flow solver; lung CFD model; fluid-structure interaction algorithm; etc.
Computational Structural Mechanics
Our CSM research includes static, dynamic, and aeroelastic analyses of complex solid-bodies using computational approaches such as finite element and meshless methods and multi-body dynamics. Applications include hypervelocity ballistic impact and blast simulations for defense and national security, composite body armor systems, vehicle crashworthiness, traumatic injury biomechanics, and sports mechanics.
The objective of this research is provide more comprehensive understanding of injury mechanisms of human body exposed to high-speed impact environments such as motor vehicle crashes through numerical modeling and simulation. Ongoing efforts are: (1) the development of age-dependent pediatric finite element models with medical imaging processes; (2) the development of computational methodology that loosely or strongly couples multibody and finite element analyses to evaluate the brain injuries; and (3) the modeling and simulation of obese populations to investigate obesity-related injuries on motor vehicle crashes by coupling of multibody and finite element models
The goal of this research is to develop efficient and robust algorithms for a loosely-coupled fluid-structure interaction framework that takes advantages of reusability of well-validated simulation codes for fluid and structural analyses. The framework includes several modules for: (1) efficient and accurate load and motion transfer between unmatched meshes utilized in different disciplines; (2) efficient moving grid algorithms; and (3) time mapping techniques. Examples in applied research via the framework are an analysis on aeroelastic instability of a flexible aircraft wing and a hemodynamic analysis of a compliant blood vessel.
The focus of this research is to develop an integrated design system by combining our computational simulation and grid generation capabilities with a simulation based statistical multidisciplinary design optimization module to provide an optimum design that shortens the development period for new designs and improves current designs. Under this effort, an efficient aerodynamic shape optimization framework was developed by integrating a parametric grid generator, a flow solver, and a surrogate-based optimization technique. In addition, a vehicle crashworthiness optimization framework was developed by integrating an explicit dynamic finite element solver and an optimization toolkit.