the present research simulates time-periodic unsteady transonic flow around pitching airfoils via the solution of unsteady euler and navier-stokes equations, using time spectral method (tsm) and compares it with the traditional methods such as bdf and explicit structured adaptive grid method. the tsm uses a fourier representation in time and hence solves for the periodic state directly accordin...

A novel method to estimate unsteady aerodynamic force coefficients from pointwise velocity measurements is presented. The methodology is based on a resolvent-based reducedorder model which requires the mean flow to obtain physical flow structures and pointwise measurement to calibrate their amplitudes. A computationally-affordable time-stepping methodology to obtain resolvent modes in non-trivi...

The present study deals with the analysis of unsteady boundary layer flow and heat transfer of an incompressible micropolar fluid over a stretching sheet when the sheet is stretched in its own plane. The velocity and temperature are assumed to vary linearly with the distance along the sheet. Two equal and opposite forces are impulsively applied along the x-axis so that the sheet is stretched, k...

In petroleum production, Produced Water Re-Injection (PWRI) has earned much interest among disposal methods of the produced water. However, presence of the contaminants in the produced waters usually results in formation damage in well bores and their surrounding fracture systems. In the present study, modeling of external cake formation on a fracture in unsteady-state conditions i...

The aim of this study is to propose a computing method to obtain a detailed simulation of the unsteady flow that develops in multistage turbomachines. The three-dimensional unsteady Reynolds-Averaged Navier-Stokes equations are solved using a structured multiblock decomposition method. Although this kind of flow solver is very popular in the turbomachine community nowadays, the complex block co...

Turbulent bursting events play a major role in natural systems in terms of sediment scour, transport and accretion as well as contaminant mixing and dispersion. The "bursts" were extensively studied in laboratory experiments under steady flow conditions, but rarely tested in unsteady natural flows. Herein a technique is described for the detection and analysis of turbulent events within large c...

Research in convective heat transfer using suspensions of nanometer-sized solid particles in base liquids started only over the past decade. Recent investigations on nanofluid, as such suspensions are often called, indicate that the suspended nanoparticles remarkably change the transport properties and heat transfer characteristics of the suspension. Bending walls can also improve heat transfer...

Effect of altitude is discussed in the unsteady separation of multi stage rockets. Axisymmetric, unsteady and turbulent Navier stokes equations are solved numerically. The governing equations are split into a hyperbolic inviscid part and a parabolic diffusion part. The hyperbolic part is solved by an explicit second-order time and space of Godunov-type scheme. Moving mesh and moving boundary al...

Simulation results on dynamic yaw stability derivatives of a gull bird by means of computational fluid dynamics are presented. Two different kinds of motions are used for determining the dynamic yaw stability derivatives Nr C and β& N C . Concerning the first one, simple lateral translation and yaw rotary motions in yaw are considered. The second one consists of combined motions. To determine d...

A hardware-based approach for visualizing unsteady flow fields by means of Lagrangian-Eulerian advection is presented. Both noise-based and dyebased texture advection is supported. The implementation allows the advection of each texture to be performed completely on the graphics hardware in a single-pass rendering. We discuss experiences with the interactive visualization of unsteady flow field...