Improved Non-Intrusive Uncertainty Propagation in Complex Fluid Flow Problems

The problem of non-intrusive uncertainty quantification is studied, with a focus on two computational fluid dynamics cases. A collocation method using quadrature or cubature rules is applied, where the simulations are selected deterministically. A one-dimensional quadrature rule is proposed which is nested, symmetric, and has positive weights....

Development of an accurate method for advection problems with embedded moving-boundaries

An accurate method, using a novel immersed-boundary approach, is presented for numerically solving advection problems. As is standard in immersed-boundary methods, moving bodies are embedded in a fixed, ‘Cartesian,’ finite-volume grid. The essence of the present method is that specific fluxes in the vicinity of a moving body are computed in such...

Aerodynamic shape parameterisation and optimisation of novel configurations

The Multi-Disciplinary Design Optimisation (MDO) process can be supported by partial automation of analysis and optimisation steps. Design and Engineering Engines (DEE) are useful concepts to structure this type of automation. Within the DEE, a product can be parameterically defined using Knowledge Based Engineering (KBE). This parameteric...

A Monotone, Higher-Order Accurate, Fixed-Grid Finite-Volume Method for Advection Problems with Moving Boundaries

A Runge-Kutta Discontinuous-Galerkin Level-Set Method for Unsteady Compressible Two-Fluid Flow

In this work a numerical method for the solution of the two-dimensional Euler equations describing unsteady compressible two-fluid flow is presented. The method is based on the combination of a Runge-Kutta discontinuous Galerkin discretization of the Euler equations and a level-set method for the treatment of the two-fluid interface. The...

Accurate and efficient computation of steady water flow with surface waves and turbulence

A surface capturing method is developed for steady water-air flow with gravity. Second-order accuracy is obtained with flux limiting and turbulence is modeled with Menter's model. The model is solved efficiently with a combination of multigrid and defect correction. Results for two test cases confirm the efficiency and accuracy of the method.

Aspects of goal-oriented model-error estimation in convection-diffusion problems

For goal-oriented model adaptation a model-error estimator is required to drive the adaptation process. In recent years publications have appeared on the dual-weighted residual (DWR) method in the application of model-error estimation in output functionals. In this paper we study the application of the DWR method for convection-diffusion...

Aerodynamic Shape Optimization by means of Sequential Linear Programming Techniques

An optimization framework for aerodynamic design on unstructured meshes has been implemented. It includes a finite volume solver based upon a median-dual discretization, its discrete adjoint, and shape parameterization and mesh moving/deforming algorithms. The framework elements are coupled and linked to a Sequential Quadratic Programming (SQP)...

Computational fluid dynamics: Wetenschap en gereedschap

A computational method for high-frequency oleodynamics, application to hydraulic-shock-absorber designs

A computational method for oleo-acoustics, application to hydraulic shock absorbers

Multigrid and defect correction for the steady Navier-Stokes. application to aerodynamics

Numerical solution of transonic normal shock wave-boundary layer interaction using the Bohning-Zierep model