Numerical Study of Three-Dimensional Flows Using Unfactored Upwind-Relaxation Sweeping Algorithm

Zha, Gecheng; Bilgen, E.

doi:10.1006/jcph.1996.0104

Cited by 69 publications

(14 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The low diffusion E-CUSP scheme used as the approximate Riemann solver suggested by Zha et al [22] is utilized with the WENO scheme to evaluate the inviscid fluxes. Implicit time marching method using Gauss-Seidel line relaxation is used to achieve fast convergence rate [28]. Parallel computing is implemented to save wall clock simulation time [29].…”

Section: Modeling Parametersmentioning

confidence: 99%

Performance of a Co-Flow Jet Airfoil with Variation of Mach Number

Lefebvre

Dano

Difronzo

et al. 2013

51st AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition

View full text Add to dashboard Cite

This paper conducts numerical investigations for a 15% thickness Co-Flow Jet (CFJ) airfoil performance enhancement, which includes the variation of lift, drag, and energy expenditure at Mach number 0.03, 0.3, and 0.4 with jet momentum coefficient Cµ = 0.08. The angle of attack(AoA) varies from 0 • to 30 • . Two-dimensional simulation is conducted using a Reynolds-averaged Navier-Stokes (RANS) solver. A 5th order WENO scheme for the inviscid flux and a 4th order central differencing for the viscous terms are used to resolve the the Navier-Stokes equations. Turbulence is simulated with the one equation Spalart-Allmaras model.The study shows that at constant Cµ, the maximum lift coefficient is increased with the increasing Mach number due to the compressibility effect. However, at M=0.4, the airfoil stalls with slightly lower AoA due to the appearance of strong λ shock wave that interrupts the jet and trigger boundary layer separation. The drag coefficients vary less with the Mach number, but is substantially increased at Mach 0.4 when the AoA is high due to shock wave-boundary layer interaction and wave drag.The power coefficient is decreased when the Mach number is increased from 0.03 to 0.3. This is again due to the compressibility effect that generates stronger low pressure suction effect at airfoil leading edge, which makes the CFJ pumping easier and require less power. For the same reason of shock appearance at M=0.4 when the AoA is high, the power coefficient is significantly increased due to large entropy increase. Overall, the numerical simulation indicates that the CFJ airfoil is very effective to enhance lift, reduce drag, and increase stall margin with high Mach number up to 0.4 at low energy expenditure.

show abstract

Section: Modeling Parametersmentioning

confidence: 99%

Performance of a Co-Flow Jet Airfoil with Variation of Mach Number

Lefebvre

Dano

Difronzo

et al. 2013

51st AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition

View full text Add to dashboard Cite

show abstract

“…The 2D Reynolds averaged Navier-Stokes (RANS) equations with one-equation Spalart-Allmaras (SA) [30] turbulence model is used. A 5th order WENO scheme for the inviscid flux [31,32,33,34,35,36] and a 4th order central differencing for the viscous terms [31,35] are employed to discretize the Navier-Stokes equations. The low diffusion E-CUSP scheme used as the approximate Riemann solver suggested by Zha et al [32] is utilized with the WENO scheme to evaluate the inviscid fluxes.…”

Section: Cfd Codementioning

confidence: 99%

“…The low diffusion E-CUSP scheme used as the approximate Riemann solver suggested by Zha et al [32] is utilized with the WENO scheme to evaluate the inviscid fluxes. Implicit time marching method using Gauss-Seidel line relaxation is used to achieve a fast convergence rate [36]. Parallel computing is implemented to save wall clock simulation time [37].…”

Section: Cfd Codementioning

confidence: 99%

Aircraft Control Surfaces Using Co-flow Jet Active Flow Control Airfoil

Zhang

Yang

et al. 2018

2018 Applied Aerodynamics Conference

View full text Add to dashboard Cite

This paper investigates the effects using high lift zero-net mass-flux Co-Flow Jet (CFJ) active flow control airfoil for aircraft control surfaces with plain flaps and with no flap. The goal is to reduce the size and weight of conventional aircraft control surfaces and save energy expenditure.Two-dimensional simulation of NACA 0012 airfoil used as a control surface is conducted for parametric trade study using a Reynolds-averaged Navier-Stokes (RANS) solver with Spalart-Allmaras (SA) model. A 5th order WENO scheme for the inviscid flux and a 4th order central differencing for the viscous terms are used to resolve the Navier-Stokes equations.The 2D numerical studies indicate that the CFJ airfoil for aircraft control surfaces with a plain flap can dramatically increase the lift coefficient and aerodynamic efficiency simultaneously compared with the conventional control surface with the same size of flap and deflection angle. CFJ airfoil control surface shows great potential to substantially reduce the size and weight of conventional aircraft control surfaces with high control authority.A series of trade study is done based on NACA0012 airfoil for control surface. The CFJ airfoil is modified from the baseline NACA0012 airfoil by translating the upper surface downward by 0.1%C. A constant deflection angle of 30° is used.The final preferred configuration has the flap length of 35%C, deflection angle of 30°, injection location at 2%C from leading edge, injection slot size of 0.5%C, and suction slot right upstream of the flap with the size twice larger than the injection size.The final trade study is to investigate the effect of injection jet momentum coefficient Cµ at 0.05, 0.15, 0.25. The lower Cµ value of 0.05 is the most energy cost effective to increase the lift coefficient. Comparing with the baseline airfoil with the same flap size and deflection angle, at sideslip angle of 0°, the case of Cµ=0.05 of the final configuration achieves a lift coefficient increase by 106.4% from CL=1.09 to 2.25 at very low power coefficient of 0.0285. At the same time, it substantially reduces the drag by 67.17%. All these compound effects result in an increase of aerodynamic efficiency(including CFJ power consumption) by 232.2%. In other words, while the CFJ control surface substantially increases the lift, it simultaneously reduces the net energy cost in a dramatical manner. This even does not count the additional benefit due to the reduced control surface size and weight Finally, CFJ airfoil with no flap is also simulated at injection jet momentum coefficient Cµ=0.05, 0.10, 0.15, 0.20, 0.25 and 0.30. The result shows that the maximum lift coefficients of 3.048 (an increase of 114%) is achieved at Cµ=0.30 with a reduced drag. The aerodynamic efficiency of the flapless control surface is not studied in this work and will be reported in future.The results indicate that flapless control surface may be a feasible option.

show abstract

“…The low diffusion E-CUSP scheme used as the approximate Riemann solver suggested by Zha et al [14] is utilized with the WENO scheme to evaluate the inviscid fluxes. Implicit time marching method using Gauss-Seidel line relaxation is used to achieve a fast convergence rate [19]. Parallel computing is implemented to save wall clock simulation time [20].…”

Section: Cfd Codementioning

confidence: 99%

Co-Flow Jet Airfoil Trade Study Part II: Moment and Drag

Lefebvre

Zha

2014

32nd AIAA Applied Aerodynamics Conference

View full text Add to dashboard Cite

This paper is Part II of a parametric study on CFJ airfoils. In the first part of the paper, the CFJ airfoil suction surface shape is modified to reduce or overcome the nose-down moment. In the second part of the paper, the injection and suction sizes and C µ are varied to increase the CFJ airfoil thrust generation. For both parts, the resulting effects on the lift, drag, moment and energy consumption is analyzed. The two dimensional flow is simulated using steady and unsteady Reynolds Average Navier-Stokes (RANS). A 5th order WENO scheme for the inviscid flux, a 4th order central differencing model for the viscous terms and the one equation Spalart-Allmaras model for the turbulence are used to resolve the flow. The Mach number is 0.15 and Reynolds number is 6.4 × 10 6. The nose-down moment of the CFJ airfoils was successfully reduced with the use of reflex camber while negative drag was achieved with a thinner airfoil, and a reduced injection size. Increasing C µ further reduces the drag, but at the cost of a much higher energy consumption and reduced corrected aerodynamic efficiency. The minimum drag achieved is C D = −0.033 and the highest moment achieved is C M = 0.031.

show abstract

Numerical Study of Three-Dimensional Flows Using Unfactored Upwind-Relaxation Sweeping Algorithm

Cited by 69 publications

References 11 publications

Performance of a Co-Flow Jet Airfoil with Variation of Mach Number

Performance of a Co-Flow Jet Airfoil with Variation of Mach Number

Aircraft Control Surfaces Using Co-flow Jet Active Flow Control Airfoil

Co-Flow Jet Airfoil Trade Study Part II: Moment and Drag

Contact Info

Product

Resources

About