This paper presents an efficient Euler method on Cartesian grids coupled with an integral Boundary-Layer method. The unsteady Euler equations are solved using cell-centered finite volume method by the implicit-explicit dual-time stepping scheme. The wall boundary conditions on the wing are implemented on the wing chord plane by first order approximation so that non-moving Cartesian grids can be...

We describe progress in classifying the convective instability characteristics of the boundarylayer flow over the family of rotating cones. Existing experimental and theoretical studies are discussed which lead to the clear hypothesis of a centrifugal instability mode that dominates over slender cones and manifests as Görtler-type spiral vortices. Although a formulation consistent with the clas...

hen marine geophysical measurements reach resolutions of ten to hundreds of meters over 1000-km regions, a new realm of analysis is opened. Such data did not exist prior to Seasat in 1978. However, the value of these data has been neglected for almost two decades. The reasons are many: Star Wars, modeler indifference, fear of a new form of data where empiricism reigns, and numerical model mysti...

A computational method is introduced to infer statistical information on boundarylayer perturbations upstream of laminar-turbulent transition in a supersonic boundary layer. The method uses the intermittency function as a basis, which specifies the amount of time a flow is turbulent at a given streamwise location. The methods yields a joint probability density function for amplitude and frequen...

We discuss the existing theoretical prediction that convective disturbances traveling between 70% and 80% of the local surface speed are the most amplified within the boundarylayer flows over rotating cones and spheres. Although most experimental observations of such flows report stationary vortices excited by surface roughnesses, we note that Kobayashi & Arai [Laminar Turbulent Transition, IUT...

An experimental investigation of swept-wing crossflow transition is carried out, focussing on the effects of chord Reynolds number and direct roughness element height (spaced at the critical crossflow wavelength) in a moderate-level disturbance facility. Flow quality measurements performed in the wind tunnel indicate turbulence intensities of urms/U∞ = 0.14% and v ′ rms/U∞ = 0.20%. The Reynolds...

The performance of transport aircraft can be considerably improved if the process by which the wing boundarylayer becomes turbulent can be controlled and extensive areas of laminar flow maintained. In order to design laminar flow control systems, it is necessary to be able to predict the movement of the transition location in response to changes in control variables e.g: surface suction. At pre...

Within the work of the EU-funded SIROCCO project new airfoils for the tip region of two reference wind turbines are being designed with the objective to reduce the trailing-edge noise while maintaining the performance. The present paper focuses on the description of the optimization tools along with the aerodynamic and aeroacoustic prediction methods used. Comparisons with detailed boundary-lay...