Active Flow Control Technique for the Reduction of Helicopter BVI Noise; a Numerical Study Using Large-Eddy Simulation

2010 ◽  
Author(s):  
Marcel Ilie
Keyword(s):  
Large Eddy Simulation ◽  
Flow Control ◽  
Numerical Study ◽  
Active Flow Control ◽  
Control Technique ◽  
Eddy Simulation ◽  
Large Eddy ◽  
Active Flow

Large Eddy Simulation of Active Flow Control Over SD7003 at Reynolds Number of 60,000

2020 ◽  
Author(s):  
Djavad Kamari ◽  
Mehran Tadjfar ◽  
Ali Tarokh
Keyword(s):  
Reynolds Number ◽  
Large Eddy Simulation ◽  
Flow Control ◽  
Turbulent Viscosity ◽  
Active Flow Control ◽  
Smagorinsky Model ◽  
Eddy Simulation ◽  
Large Eddy ◽  
Active Flow

Abstract Large Eddy Simulation for active flow control (AFC) by employing synthetic and continuous blowing is done to investigate their effects on resizing separation. The flow around an SD7003 airfoil at Reynolds number of 60,000 and angles of attack of 13° is considered where a widespread separation occurs at post stall. In this work, the Dynamic Smagorinsky model is used as to calculate the turbulent viscosity.

Very Large Eddy Simulation of Passive Drag Control for a D-Shaped Cylinder

2013 ◽  
Vol 135 (10) ◽  
Author(s):  
Xingsi Han ◽  
Siniša Krajnović
Keyword(s):  
Large Eddy Simulation ◽  
Flow Control ◽  
Control Problem ◽  
Bluff Body ◽  
Numerical Study ◽  
Numerical Results ◽  
Complex Flow ◽  
Local Disturbance ◽  
Eddy Simulation ◽  
Large Eddy

The numerical study reported here deals with the passive flow control around a two-dimensional D-shaped bluff body at a Reynolds number of Re=3.6×104. A small circular control cylinder located in the near wake behind the main bluff body is employed as a local disturbance of the shear layer and the wake. 3D simulations are carried out using a newly developed very large eddy simulation (VLES) method, based on the standard k − ε turbulence model. The aim of this study is to validate the performance of this method for the complex flow control problem. Numerical results are compared with available experimental data, including global flow parameters and velocity profiles. Good agreements are observed. Numerical results suggest that the bubble recirculation length is increased by about 36% by the local disturbance of the small cylinder, which compares well to the experimental observations in which the length is increased by about 38%. A drag reduction of about 18% is observed in the VLES simulation, which is quite close to the experimental value of 17.5%. It is found that the VLES method is able to predict the flow control problem quite well.

Numerical Analysis of Steady Blowing Based Active Flow Control for Flow Over Ahmed Body

2019 ◽  
Author(s):  
Bansal Shah ◽  
Debashis Basu
Keyword(s):  
Flow Control ◽  
Bluff Body ◽  
Stokes Equations ◽  
Numerical Study ◽  
Active Flow Control ◽  
Control Technique ◽  
Computational Time ◽  
Narrow Slit ◽  
Active Flow ◽  
Ahmed Body

Abstract A numerical study is conducted to investigate fluidic actuation with steady injection for active flow control and drag reduction in an Ahmed body. Numerical results are obtained for the unsteady three-dimensional Navier Stokes equations for both baseline as well as steady injection cases. This study examines the use of active flow control devices at the rear of the 25-deg Ahmed model to reduce drag by controlling an unsteady wake. The present work demonstrates that URANS model with grid refinement at critical locations can accurately describe the aerodynamics around the bluff body with computational time of several days compared to several weeks with traditional LES simulations. In order to modify the wake and reduce the pressure drag, active flow control technique using steady blowing was applied through a narrow slit along all rear edges of the model. The effect of inlet velocity for the baseline simulations was analyzed. Computed Results showed AFC achieves significant reduction in the drag coefficient (Cd) values over the baseline simulations.

Sign in / Sign up

Export Citation Format

Share Document