Abstract A Reduced-Order Model (ROM) is developed for the prediction of unsteady transonic flows past an airfoil submitted to small deformations, at moderate Reynolds number. Considering a suitable state formulation as well as a consistent inner product, the Galerkin projection of the compressible flow Navier-Stokes equations, the High-Fidelity (HF) model, onto a low-dimensional basis determine...

AbstrAct: Design candidates obtained from optimization techniques may have meaningful information, which provides not only the best solution, but also a relationship between object functions and design variables. In particular, trade-off studies for optimum airfoil shape design involving various objectives and design variables require the effective analysis tool to take into account a complexit...

The Prediction of aerodynamic characteristics and shape optimization of airfoil under the ground effect have been carried out by integration of computational fluid dynamics and the multiobjective Pareto-based genetic algorithm. The main flow characteristics around an airfoil of WIG craft are lift force, lift-to-drag ratio and static height stability (H.S). However, they show a strong trade-off ...

To analyse the sensitivity of blade geometry and airfoil characteristics on the prediction of performance characteristics of wind farms, large-eddy simulations using an actuator disc (ACD) method are performed for three different blade/airfoil configurations. The aim of the study is to determine how the mean characteristics of wake flow, mean power production and thrust depend on the choice of ...

A design procedure for subscale airfoils with full-scale leading edges that exhibit full-scale water droplet impingement characteristics in an incompressible, inviscid  ow is presented. The design procedure uses validated airfoil design,  ow analysis, and water droplet impingement simulation codes to accomplish the task. To identify and isolate important design variables in the design, numero...

Shape optimization of the airfoil with high aspect ratio of long endurance unmanned aerial vehicle (UAV) is performed by the multi-objective optimization technology coupled with computational fluid dynamics (CFD). For predicting the aerodynamic characteristics around the airfoil the high-fidelity Navier-Stokes solver is employed and SMOGA (Simple Multi-Objective Genetic Algorithm), which is dev...

CST method is a powerful parameterization method because of its simplicity, robustness, and its ability to be generalized into various possible shapes of aerodynamic bodies. The geometry from CST itself is mainly determined by the formula of class and shape function. Application of CST to transonic airfoil optimization is still rare and more studies are needed. This work studies the application...

To control the Karman vortex street formed behind a thin airfoil at a certain incidence, a control cylinder was placed at the suction side apart from the airfoil in the downstream region. Both smoke visualization and hot-wire measurements confirmed that the Karman vortex street was completely suppressed. The mechanism for suppression of the vortex street was examined with a hot-wire survey.

Increasing the combustion temperatures in a gas turbine engine to achieve higher efficiency and power output also results in high heat loads to turbine components downstream of the combustor. The challenge of adequately cooling the nozzle guide vane directly downstream of the combustor is compounded by a complex vortical secondary flow at the junction of the endwall and the airfoil. This flow t...

Flow and turbulence models applied to the problem of shock bu et onset are studied. The accuracy of the interactive boundary layer and the thin-layer Navier-Stokes equations solved with recent upwind techniques using similar transport eld equation turbulence models is assessed for standard steady test cases, including conditions having signi cant shock separation. The two methods are found to c...