The objective of this paper is to study the effect of an unsteady moving heat source on the aerodynamic performance of an NACA 0012 airfoil section, with particular focus on the lift and drag coefficients. The compressible Navier–Stokes equations are solved using a finite volume method as well as Spalart-Allmaras Model for turbulence simulation. The heat source periodically moves over the lower...

Abstract―This paper illustrates the theory behind computational fluid dynamics (CFD) of flow though a gas turbine engine low pressure compressor. The goal of study is to develop a tool to perform shape optimization of low speed airfoils. Mathematical model and computational tool are developed using programming software. Analytical solution is developed to create airfoil geometry. The NACA 4 dig...

EI ρA Wn(x) eigenfunction corresponding to the n th eigenvalue Tn(t) generalized function corresponding to the n th eigenvalue Fn(t) forcing function in terms of the n th eigenmode z the deflection of the beam in the complex plane x nondimensional length scale by chord length of the NACA0012 airfoil κ Reduced plunging frequency, ωc U∞ h non-dimensional amplitude,y/c ha maximum nondimensional am...

This work presents a numerical analysis of the ability of the high lift airfoil profile Selig S1223 for working as hydrofoil under water conditions. The geometry of the hydrofoil blade is designed through a suitable airfoil profile and then studied carefully by means of Computational Fluid Dynamics (CFD) in order to check its hydrodynamic behavior, i.e., including lift and drag analysis, and de...

A novel spectral-element approach for the eikonal equation is presented based on the work of Tucker et al. This approach is readily implemented in standard finiteelement flow solvers developed for the Navier-Stokes equations. Results are presented for distance function (level set) for three planar configurations: circular cylinder, NACA 0012 airfoil, and T106 airfoil. Results demonstrate that t...

This paper presents simulations of unsteady flow past a plunging airfoil using the highorder spectral difference (SD) method. Both third-order and fourth-order SD methods are used on unstructured quadrilateral grids. The vortex shedding pattern of an airfoil in an oscillating plunge motion becomes asymmetric at a sufficiently high frequency. The SD method is able to capture this effect and reve...

The interaction between wakes of bluff body and airfoil have profound influences on system performance in many industrial applications, e.g., turbo-machinery and cooling fan. The present work investigates the effect of configuration include; airfoil’s angle of attack, transverse and inline spacing of the models, on frequency behavior of the cylinder’s near-wake. The experiments carried on under...

In the present paper, the influence of a pressure gradient on the acoustic roughness receptivity is investigated by means of wind tunnel experiments and Direct Numerical Simulations (DNS). The receptivity function for three different locations of a 3-D surface non-uniformity on a 2-D airfoil is calculated from the experimental and numerical data and compared to each other. The combined effects ...

This paper deals with a numerical method for an airfoil design. It is shown how to create an airfoil from a given velocity distribution along a mean camber line. The method is based on searching a fixed point of a contractive operator. We need to have a fast solver of the Euler equations. The Newton method for solving implicit finite volume scheme is described. The resulting system of linear al...

We analyze the laser ellipticity dependence of n-photon differential cross sections (dσn/dΩ) for electron-atom scattering in an intense elliptically polarized laser field. We show that there exist two plateau-like structures in the dependence of dσn/dΩ on n for any ellipticity, including for the case of circular polarization. We present numerical predictions for e-H scattering in a CO2-laser fi...