Linear instability of Poiseuille flows with highly non-ideal fluids

The objective of this work is to investigate linear modal and algebraic instability in Poiseuille flows with fluids close to their vapour-liquid critical point. Close to this critical point, the ideal gas assumption does not hold and large non-ideal fluid behaviours occur. As a representative non-ideal fluid, we consider supercritical carbon...

A parametric study of laminar and transitional oblique shock wave reflections

High-resolution particle image velocimetry measurements were performed on laminar and transitional oblique shock wave reflections for a range of Mach numbers (M D 1:6-2:3), Reynolds numbers (Re_xsh D 1.4×10⁶-3.5×10⁶) and flow deflection angles (θ 1°-5° or p3=p1 D 1.11-1.64). The laminar interactions revealed a...

Models and simulation of non-ideal fluid flows in unconventional turbomachinery: Toward highly efficient next-generation green power systems

The new generation of power plants based on innovative thermodynamic cycles operating with unconventional working fluids, such as CO2 close to its thermodynamic critical point or organic fluids close to their vapour saturation line, is an attractive option for high efficiency conversion of sustainable energy sources in the low and medium power...

A scaling analysis for turbulent shock-wave/boundary-layer interactions

A model based on mass conservation properties is developed for shock-wave/boundarylayer interactions (SWBLIs), aimed at reconciling the observed great diversity in flow organization documented in the literature, induced by variations in interaction geometry and aerodynamic conditions. It is the basis for a scaling approach for the interaction...

Flow of a viscous compressible fluid produced in a circular tube by an impulsive point source

The flow of a viscous compressible fluid in a circular tube generated by a sudden impulse at a point on the axis is studied on the basis of the linearized Navier–Stokes equations. A no-slip boundary condition is assumed to hold on the wall of the tube. An efficient numerical scheme has been developed for the calculation of flow velocity and...

Numerical modelling of compressible two-phase flows

This paper presents a hierarchy of compressible two-phase flow models. It is shown that using Chapman-Enskog expansions in the limit of zero relaxation time toward the various equilibria that exist in these flows, a full set of models of decreasing complexity can be constructed. At the top of this hierarchy, we have a complete seven equation...

The Weighted Least Square Scheme for Multidimensional Flows

This article describes the development of a high order finite volume method for the solution of transonic flows. The high order of accuracy is achieved by a reconstruction procedure similar to the weighted essentially non-oscillatory schemes (WENO). On the contrary to the WENO schemes, the weighted least square (WLSQR) scheme is easily...

Low dissipative methods for turbulent reacting flows

Modeling of scalar transport is an essential point in the simulation of non-premixed turbulent combustion. The fuel and oxidizer streams are, in general, modeled with an equation for the mixture fraction Z. This mixture fraction is a bounded function, i.e. it can never become large than one or smaller than zero. Symmetric central differencing...

Low dissipative methods for turbulent reacting flows

Modeling of scalar transport is an essential point in the simulation of non-premixed turbulent combustion. The fuel and oxidizer streams are, in general, modeled with an equation for the mixture fraction $Z$. This mixture fraction is a bounded function, i.e. it can never become large than one or smaller than zero. Symmetric central differencing...

Recent advances in the immersed boundary method

In this paper we discuss some of the recent advances in the immersed boundary (IB) method. More specifically, we show the application of this technique to problems with strong fluid/structure interaction and to compressible flows using local mesh refinement. These extensions are a must for the success of the IB method in industrial applications.

Time dependent adaptation for compressible flows

The paper deals with the algorithm for unsteady anisotropic adaptation. The adaptation is using the remeshing approach to create a new refined grid. The grid is generated in computational space defined by metric field based on the tensor error indicator. The verification of the method is done first for 2D supersonic flow in a channel with...

Error estimation and adjoint-based adaptation in aerodynamics

We give an overview of recent developments in error estimation and in residual-based and goal-oriented (adjoint-based) adaptation for Discontinuous Galerkin discretizations of sub- and supersonic viscous compressible flows. We also give an outlook on the planned continuation of this research in the EU project ADIGMA.