Computational vorticity capturing - Application to helicopter rotor flows

Steinhoff, John; Wenren, Yonghu; Mersch, Thomas; Senge, Heinrich

doi:10.2514/6.1992-56

Cited by 22 publications

(5 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In hybrid approaches, several different methods complement each other. For example, Steinhoff, et al 15 combined a vorticity capturing method with a Navier-Stokes method to reduce artificial dissipation effects on rotor wake vortices, which in turn relaxes the grid resolution requirement to resolve and maintain a rotor wake vortex in the solution procedure. Boyd and Barnwell 16 first introduced a hybrid method that loosely couples a Generalized Dynamic Wake Theory [17][18][19][20] (GDWT) with a Navier-Stokes method.…”

Section: Hybrid Methodsmentioning

confidence: 99%

A computational model for rotor-fuselage interactional aerodynamics

Boyd

Richard

Susan

2000

38th Aerospace Sciences Meeting and Exhibit

View full text Add to dashboard Cite

A novel unsteady rotor-fuselage interactional aerodynamics model has been developed. This model loosely couples a Generalized Dynamic Wake Theory (GDWT) to a thin-layer Navier-Stokes solution procedure. This coupling is achieved using an unsteady pressure jump boundary condition in the Navier-Stokes model. The new unsteady pressure jump boundary condition models each rotor blade as a moving pressure jump which travels around the rotor azimuth and is applied between two adjacent planes in a cylindrical, non-rotating grid. Comparisons are made between measured and predicted time-averaged and time-accurate rotor inflow ratios. Additional comparisons are made between measured and predicted unsteady surface pressures on the top centerline and sides of the fuselage.

show abstract

Section: Hybrid Methodsmentioning

confidence: 99%

A computational model for rotor-fuselage interactional aerodynamics

Boyd

Richard

Susan

2000

38th Aerospace Sciences Meeting and Exhibit

View full text Add to dashboard Cite

show abstract

“…The vorticity confinement (VC) model used in this work was first introduced by Steinhoff et al (1992) and Steinhoff and Underhill (1994) . The model was initially developed to overcome the problems of numerical diffusion of vortices and to enable low cost simulation on coarse Eulerian grids without the use of high order spatial and temporal discretisation schemes.…”

Section: Vorticity Confinement Modelmentioning

confidence: 99%

A vorticity confinement model applied to URANS and LES simulations of a wing-tip vortex in the near-field

O’Regan

Griffin

Young

2016

International Journal of Heat and Fluid Flow

View full text Add to dashboard Cite

“…Over the past decades, the VC1 formulation became attractive in the simulation of vortexdominated flows due to its algorithmical simplicity and efficiency, especially for helicopter rotor flows. For instance, Steinhoff et al [17] first applied the VC1 to hovering HELIX I rotor flows and received a promising result. Biava and Vigevano [8] investigated the variation of confinement parameters on thrust coefficient for ONERA 7A four-bladed rotor flows in both hover and forward flight.…”

Section: Introductionmentioning

confidence: 99%

Assessment of the Vortex Feature-Based Vorticity Confinement Method Applied to Rotor Aerodynamics and Aeroacoustics

Vigevano

2023

Aerospace

View full text Add to dashboard Cite

The accurate prediction of helicopter rotor aerodynamics and aeroacoustics using Computational Fluid Dynamics (CFD) techniques still remains a challenge, as the over-dissipation of numerical schemes results in a higher diffusive rate of rotor wake and vortices than what can be expected from the fluid governing equations. To alleviate this issue, a vortex feature-based vorticity confinement (FVC2-L2) method that combines the locally normalized λ2 vortex detection method with the standard second vorticity confinement (VC2) scheme is presented to counterbalance the truncation error introduced by the numerical discretization of the convective term while avoiding the over-confinement inside the boundary layer. The FVC2-L2 scheme is adopted for helicopter rotor aerodynamic and aeroacoustic predictions through its implementation in the multi-block structured grid CFD solver ROSITA and coupling with the aeroacoustic code ROCAAP based on the permeable surface Ffowcs Williams–Hawkings (PS-FWH) equation. This approach is assessed in helicopter rotor flows via three databases. Firstly, the well-documented HART-II rotor in the baseline condition is used to evaluate the capability of the presented VC scheme in blade–vortex interaction (BVI) phenomena prediction. Subsequently, the UH-1H non-lifting hovering rotor and the AH-1/OLS low-speed descending flight rotor are adopted for assessment of such a method in aeroacoustics. The benefits of the FVC2-L2 scheme in terms of aerodynamics prediction, wake preservation, and noise signal prediction are well demonstrated by comparison with the experimental data and the results obtained without VC schemes. Particularly, the FVC2-L2 scheme mainly improves the highly unsteady airloads prediction, and results in an improvement of BVI noise prediction by more than 5 dB with respect to the case without VC schemes for AH-1/OLS rotor case. Additionally, some shortcomings of the approach are noticed in engineering applications. On the basis of a simplified convective vortex, some provisional guidelines on the required εo value in terms of number of cells per vortex diameter are provided: an εo value ranging from 0.01 to 0.04 for grids which may represent the vortex core diameter with 6 to 12 cells.

show abstract

Computational vorticity capturing - Application to helicopter rotor flows

Cited by 22 publications

References 6 publications

A computational model for rotor-fuselage interactional aerodynamics

A computational model for rotor-fuselage interactional aerodynamics

A vorticity confinement model applied to URANS and LES simulations of a wing-tip vortex in the near-field

Assessment of the Vortex Feature-Based Vorticity Confinement Method Applied to Rotor Aerodynamics and Aeroacoustics

Contact Info

Product

Resources

About