Numerical analysis of transport aircraft using different wing tip devices

An integrated design and manufacturing approach allows economic decisions to be made that reflect an entire system design as a whole. To achieve this objective, we have developed and utilized integrated cost and engineering models within a focused design perspective. A framework for the integrated design of an aircraft system with a combined performance and economic perspective is described in this article. This framework is based on the concept of Design Justification using a Design-for-Economics approach. We have developed a knowledge-based system that can be used to evaluate aircraft structural concept material and process selections. The framework consists of the knowledge-based system, integrated with numerical analysis tools including an aircraft performance/sizing code and a life-cycle cost analysis code. Production cost estimates are applied for evaluation of process trades at the subcomponent level of design. Life-cycle cost estimates are used for evaluation of process trades at the system level. Results of a case study are presented for several advanced wing structural concepts for a future supersonic commercial transport aircraft. Cost versus performance studies indicate that a high-speed civil transport aircraft with a hybrid wing structural concept, though more expensive to manufacture than some homogeneous concepts, can have lower direct operating costs due to a lower take-off gross weight and less mission fuel required.

Download Full-text

On wake vortex response for all combinations of five classes of aircraft

The Aeronautical Journal ◽

10.1017/s0001924000000154 ◽

2004 ◽

Vol 108 (1084) ◽

pp. 295-310 ◽

Cited By ~ 3

Author(s):

L. M. B. C. Campos ◽

J. M. G. Marques

Keyword(s):

Wake Vortex ◽

Dimensionless Form ◽

Bank Angle ◽

Rolling Moment ◽

Tip Vortices ◽

Transport Aircraft ◽

Roll Rate ◽

Wing Tip ◽

Special Case ◽

Light Medium

Abstract The present paper concerns the response of a following airplane to a pair of wing tip vortices left by a leading aircraft, represented by the Hallock-Burnham model, including the effect of vorticity decay between the two aircraft. The effect of vorticity is evaluated in terms of the induced rolling moment and also the lift loss; these specify the roll acceleration and the downward acceleration, respectively. The corresponding two response equations can be put into the same dimensionless form, and integrated using exponential integrals. This specifies the roll rate and sink rate as a function of time; besides the latter, the bank angle and altitude loss, are also plotted, all also as a function of time, for all combinations of leading and following aircraft in five classes. These are the three ICAO weight categories of light, medium and heavy, plus two other cases, viz the special case of the Boeing 757, which requires larger separations distances, and the case of a future very large transport aircraft (VLTA) exceeding significantly the size of a Boeing 747.

Download Full-text

Numerical Analysis of Wing-Tip Flows and Aerodynamic Sound Generated From the Flows

ASME-JSME-KSME 2011 Joint Fluids Engineering Conference: Volume 1, Symposia – Parts A, B, C, and D ◽

10.1115/ajk2011-08039 ◽

2011 ◽

Author(s):

Kazuaki Yamasari ◽

Yasumasa Suzuki ◽

Chisachi Kato ◽

Masaaki Ohnishi ◽

Kentaro Yatuduka ◽

...

Keyword(s):

Numerical Analysis ◽

Measured Data ◽

Sound Level ◽

Tip Vortex ◽

Far Field ◽

Aerodynamic Sound ◽

Eddy Simulation ◽

Surface Pressure Distribution ◽

Wing Tip ◽

Field Sound

We study the flow and the aerodynamic sound generated from the wing-tip using numerical analysis. The objective of this study is to clarify the contribution to level of sound generated from the wing-tip. We predicted the aerodynamic sound by the separation method based on Lighthill analogy. The model is a rectangular wing having NACA0012 profiles. The shape of wing-tip is blunt, which has sharp edges. The Reynolds number based on the chord length and uniform velocity is 2×105. The angle of attack is 9 degree which is the lifting condition. The flow around the airfoil is predicted by Large-eddy simulation of turbulent incompressible flow. Current results indicated that the simulated surface pressure distribution and pressure power spectrum agreed quantitatively with measured data. In this result, we calculated the Lighthill tensor from velocity and density of air. In addition we discussed the wing-tip vortex structure and its origin. The far field sound predicted by Lighthill tensor shows a similar tendency to the measured data. To investigate the contribution of the overall level around the airfoil with wing-tip, the far field sound was predicted by Lighthill tensor only around wing-tip. The aerodynamic sound level generated from wing-tip is small compared to the overall level of the sound all around airfoil, however it remains possible that contribute to particular frequency band.

Download Full-text