Brian Turnquist Mechanical Engineering Dissertation Defense
- Monday, June 29, 2020 at 10:00am
- Roberts Hall, 321 and WebEx at Meeting number: 120 776 5800 Password: kxDXRWRU356 - view map
Intrusive Uncertainty Quantification Method for Simulations of Gas-Liquid Multiphase Flows
Increasingly, simulations of fluid dynamics play a major role in the development of new technology. For example, engineers may need to simulate an atomizing jet to create a better direct injection system for improving fuel economy in a vehicle, or to more efficiently spray water for building fire mitigation systems. The growing use of computational fluid dynamics requires improvements in methodology to increase simulation efficiency and accuracy. With better models we can extract valuable data from these solutions, including uncertainty information. Although simulation of gas-liquid multiphase flow scenarios are common, most are deterministic in nature. Model parameters, like fluid density or viscosity, are assumed to be known and fixed. Unfortunately this is not usually the case, and a research gap exists for uncertainty analysis of multiphase simulations. For efficient performance, we developed an intrusive method for solving multiphase flows that is capable of uncertainty analysis. Variables of interest, such as velocity and pressure, are assumed to be functions of uncertainty. Variability is then added to fluid parameters or initial/boundary conditions and a simulation is run which produces stochastic results. To verify the solver, several cases are presented which compare the ability of the solver against analytic solutions, testing both the interface transport and velocity solution schemes. We can also answer questions about more complex scenarios. For instance, we question how uncertainty about the surface tension force may affect the atomization of a jet, or how fluid densities play a role in droplet movement. Our findings suggest multiUQ is capable of producing accurate results of real world situations, and may provide additional insight into complicated multiphase flow systems.
- Department of Mechanical & Industrial Engineering