Shervin Sammak

Quantum Computing and Its Potential for Turbulence Simulations

A tutorial is provided of quantum computing (QC) and the way it has made significant speed-up in various simulations. A review will also be provided of the large eddy simulation (LES) of turbulent flows via the stochastic filtered density function (FDF) methodology. The potentials of the quantum speed-up in FDF simulation via QC appear to be significant. This can results to a revolutionary means by which turbulence simulations can be conducted in future.

RANS Investigation of the Transitional Flow Over Stepped NLF(1)-0416

The Computational Fluid Dynamic simulation of RANS equations over NLF(1)-0416, utilized by backward facing step, is investigated for enhancement of aerodynamic characteristics. This article concentrates on the effects of step location transition point and reattachment of separated flow by backward facing step on pressure distribution and skin friction coefficient and subsequently on lift and drag. Reynolds number (based on the free stream velocity and airfoil chord) is 2.0 million. The finite volume method has been employed to numerically solve the steady state compressible Reynolds Averaged Navier-Stokes (RANS) equations with second order Roe’s scheme. Steps at different chordwise locations are chosen on both suction and pressure sides of the airfoil in order to determine their effects on skin friction, lift, lift to drag ratio and near stall behavior. In specific cases decreasing in drag is achieved due to step point on the chord followed by transition inception. The results show that all stepped studied airfoil cases experienced higher drag in comparison with base airfoil. Lift to drag ratio enhancement is seen in step on pressure side while the step extended to leading edge, this effect increases. Based on the results, delaying stall in some cases with step on suction surface is concluded.Copyright

Langevin Simulation of Turbulent Combustion

A review is presented of modern developments in Langevin simulation of turbulent reacting flows. The filtered density function (FDF) methodology is the subject of main focus as it has proven very effective for stochastic simulations in turbulent combustion. The most recent contributions in mathematical modeling of FDF, its numerical solution, and its optimization for large scale simulations are reviewed.

Computational Analysis of a Compressor Rotor With Enhanced Airfoil

In this article, a compressor rotor blade is numerically modeled and solved by a CFD code. A stepped blade with higher aerodynamic characteristics is used to investigate unstable zone and improve operational limit and compressor stall. To validate numerical data original test case compared with experimental measurements. In this study, several locations of step on suction side of blades are tried, finally the results are compared with the case with no step on blades. It is shown that, by moving the step towards the leading edge, surge is delayed due to the reattachment of flow after the step. Efficiency is also decreased but lower than previous case.Copyright