The development and application of model reduction techniques have been widely investigated for problems in unsteady aerodynamic systems, driven mainly by the need to develop effective economical computational models capturing as much flow physics as possible. These techniques which have been based on a number of approaches such as balanced truncation, Arnoldi, proper orthogonal decomposition e...

Three model problems were examined to assess the diiculties involved in using a hybrid scheme coupling ow computation with the the Ffowcs Williams and Hawkings equation to predict noise generated by v ortices passing over a sharp edge. The results indicate that the Ffowcs Williams and Hawkings equation correctly propagates the acoustic signals when provided with accurate ow information on the i...

The main purpose of this paper is to demonstrate a bionic design for the airfoil of wind turbines inspired by the morphology of Long-eared Owl's wings. Glauert Model was adopted to design the standard blade and the bionic blade, respectively. Numerical analysis method was utilized to study the aerodynamic characteristics of the airfoils as well as the blades. Results show that the bionic airfoi...

High-performance airfoils for transonic flows of Bethe–Zel’dovich–Thompson fluids are constructed using a robust and efficient Euler flow solver coupled with a multi-objective genetic algorithm. Bethe–Zel’dovich– Thompson fluids are characterized by negative values of the fundamental derivative of gasdynamics for a range of temperatures and pressures in the vapor phase, which leads to nonclassi...

The Study of river water quality interation with lakes and dam reservoirs is important from anexploitation point of view. When river water with different densities enters a lake or dam reservoir,underflow density current phenomenon occurs. Because of the density, so understandingdifferent arrays of this phenomenon Seems necessary for checking erosion and sedimentationprocesses and their managem...

Slush nitrogen (SN(2)) is a mixture of solid nitrogen and liquid nitrogen, with an average temperature of -207 °C. To investigate whether plunging a French plastic straw (commonly used for sperm cryopreservation) in SN(2) substantially increases cooling rates with respect to liquid nitrogen (LN(2)), a numerical simulation of the heat conduction equation with convective boundary condition was us...

A significant challenge to the application of evolutionary multiobjective optimization (EMO) for transonic airfoil design is the often excessive number of computational fluid dynamic (CFD) simulations required to ensure convergence. In this study, a multiobjective particle swarm optimization (MOPSO) framework is introduced, which incorporates designer preferences to provide further guidance in ...

Abstract. A gradient based method is presented for optimization of an airfoil configuration. The flow is governed by two dimensional, compressible Euler equations. A finite volume code based on unstructured grid is developed to solve the equations. The procedure is carried out for optimizing an airfoil with initial configuration of NACA 0012. The advantage of this technique over the other gradi...