Numerical Simulations for Transport Aircraft High-Lift Configurations Using Adaptive Cartesian Grid Methods

In recent years, various strategies for the concurrent operation of fixed-and rotary-wing aircraft have been proposed as a means of increasing airport capacity. Some of these strategies will increase the likelihood of encounters with the wakes of aircraft operating nearby. Several studies now exist where numerical simulations have been used to assess the impact of encounters with the wakes of large transport aircraft on the safety of helicopter operations under such conditions. This paper contrasts the predictions of several commonly-used numerical simulation techniques when each is used to model the dynamics of a helicopter rotor during the same idealised wake encounter. In most previous studies the mutually-induced distortion of the wakes of the rotor and the interacting aircraft has been neglected, yielding the so-called ‘frozen vortex’ assumption. This assumption is shown to be valid only when the helicopter encounters the aircraft wake at high forward speed. At the low forward speeds most relevant to near-airfield operations, however, injudicious use of the frozen vortex assumption may lead to significant errors in predicting the severity of a helicopter’s response to a wake encounter.

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High-lift design methodology for subsonic civil transport aircraft

2000 IEEE Aerospace Conference. Proceedings (Cat. No.00TH8484) ◽

10.1109/aero.2000.878216 ◽

2002 ◽

Author(s):

C.P. van Dam ◽

J.K. Paris ◽

J.C. Vander Kam

Keyword(s):

Design Methodology ◽

High Lift ◽

Transport Aircraft

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Positivity-Preserving Runge-Kutta Discontinuous Galerkin Method on Adaptive Cartesian Grid for Strong Moving Shock

Numerical Mathematics Theory Methods and Applications ◽

10.4208/nmtma.2015.m1416 ◽

2016 ◽

Vol 9 (1) ◽

pp. 87-110 ◽

Cited By ~ 8

Author(s):

Jianming Liu ◽

Jianxian Qiu ◽

Mikhail Goman ◽

Xinkai Li ◽

Meilin Liu

Keyword(s):

Discontinuous Galerkin ◽

Compressible Flows ◽

Strong Shock ◽

Interpolation Formula ◽

Cartesian Grid ◽

Immersed Boundary ◽

Positivity Preserving ◽

Element Space ◽

Runge Kutta ◽

Adaptive Cartesian Grid

AbstractIn order to suppress the failure of preserving positivity of density or pressure, a positivity-preserving limiter technique coupled withh-adaptive Runge-Kutta discontinuous Galerkin (RKDG) method is developed in this paper. Such a method is implemented to simulate flows with the large Mach number, strong shock/obstacle interactions and shock diffractions. The Cartesian grid with ghost cell immersed boundary method for arbitrarily complex geometries is also presented. This approach directly uses the cell solution polynomial of DG finite element space as the interpolation formula. The method is validated by the well documented test examples involving unsteady compressible flows through complex bodies over a large Mach numbers. The numerical results demonstrate the robustness and the versatility of the proposed approach.

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