Effects of wing twist on lift and drag characteristics of blended wing body aircraft

Abstract Blended Wing Body is a revolutionary concept offering phenomenal performance advantages over conventional aircraft. There are various aerodynamic features that are added to the wing in order to adjust the lift distribution and wing twist is one of them. This paper presents a progressive study to examine the effects of twist angles on the aerodynamic characteristics of a Blended Wing Body (BWB) aircraft. CFD analysis is carried out on seven BWB models having wing twists ranging from +3° to -3°. Each model is analyzed at four different Mach numbers. The coefficient of drag (Cd) and coefficient of lift (Cl) is determined and plotted against the twist angle to obtain a trend. The Cl/Cd ratio is also calculated to observe the overall aerodynamic performance of the BWB.

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AERODYNAMIC OF UITM'S BLENDED-WING-BODY UNMANNED AERIAL VEHICLE BASELINE-II EQUIPPED WITH ONE CENTRAL VERTICAL RUDDER

Jurnal Teknologi ◽

10.11113/jt.v75.5221 ◽

2015 ◽

Vol 75 (8) ◽

Cited By ~ 1

Author(s):

Wirachman Wisnoe ◽

Rizal E.M. Nasir ◽

Ramzyzan Ramly ◽

Wahyu Kuntjoro ◽

Firdaus Muhammad

Keyword(s):

Unmanned Aerial Vehicle ◽

Cfd Simulation ◽

Aerodynamic Characteristics ◽

Control Surface ◽

Wind Tunnel Experiments ◽

Aerodynamic Parameter ◽

Aerial Vehicle ◽

Computational Fluid Dynamics Cfd ◽

Blended Wing Body ◽

Lift And Drag

In this paper, a study of aerodynamic characteristics of UiTM's Blended-Wing-Body Unmanned Aerial Vehicle (BWB-UAV) Baseline-II in terms of side force, drag force and yawing moment coefficients are presented through Computational Fluid Dynamics (CFD) simulation. A vertical rudder is added to the aircraft at the rear centre part of the fuselage as yawing control surface. The study consists of varying the side slip angles for various rudder deflection angles and to plot the results for each aerodynamic parameter. The comparison with other yawing control surface for the same aircraft obtained previously are also presented. For validation purpose, the lift and drag coefficients are compared with the results obtained from wind tunnel experiments.

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Aerodynamic analysis and design of Busemann biplane: towards efficient supersonic flight

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410011404656 ◽

2011 ◽

Vol 226 (2) ◽

pp. 217-238 ◽

Cited By ~ 1

Author(s):

D Maruyama ◽

K Kusunose ◽

K Matsushima ◽

K Nakahashi

Keyword(s):

Mach Number ◽

Design Method ◽

Three Dimensional ◽

Aerodynamic Characteristics ◽

Aerodynamic Performance ◽

The Body ◽

Analysis And Design ◽

Expansion Waves ◽

Mach Numbers ◽

Inverse Design Method

Aiming to realize a low-drag supersonic transport, Busemann biplane concept was adopted in this study. Two- and three-dimensional (2D and 3D) biplanes were analysed and designed to improve their aerodynamic performance using computational fluid dynamics. It was confirmed that 3D biplane wings have better aerodynamic-performance areas than 2D biplane airfoils. A winglet is also useful for improvement of their aerodynamic performance. Aerodynamic characteristics of these biplanes at their off-design conditions were also analysed. In 3D wings, a flow choking and its attendant hysteresis as starting problems, which arise when the biplanes accelerate from low Mach numbers, disappear at lower Mach numbers than those in 2D airfoils. It was confirmed that hinged slats and flaps are effective to settle these issues. Finally, interference effects of a body with the biplanes were investigated. When the biplane wings are affected by the expansion waves from the body, their aerodynamic performance at the design Mach number and the starting Mach number are better and lower than those of their isolated wings, respectively. A 3D biplane wing obtained by an inverse-design method was applied to the body. The wing of this wing–body configuration achieves higher aerodynamic performance than the 2D flat-plate airfoil at sufficient lift conditions, which is the almost identical performance of 2D biplane airfoils.

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The Effect of Spoiler Shape and Setting Angle on Racing Cars Aerodynamic Performance

Indonesian Journal of Science and Technology ◽

10.17509/ijost.v5i1.22701 ◽

2020 ◽

Vol 5 (1) ◽

pp. 11-20

Author(s):

Hesam Eftekhari ◽

Abdulkareem Sh. Mahdi Al-Obaidi ◽

Shahrooz Eftekhari

Keyword(s):

Drag Coefficient ◽

Aerodynamic Characteristics ◽

Aerodynamic Performance ◽

Ansys Fluent ◽

Aerodynamic Efficiency ◽

Race Car ◽

Setting Angle ◽

Being There ◽

Lift And Drag ◽

Lift And Drag Coefficient

Automotive racing is one of the favorite sports of human being. There have been many developments in past decades by car engineers to improve the performance of the engine and increase the aerodynamic efficiency of the race cars to achieve a better lap time and get a better placement safely. One of the ways to improve the aerodynamic performance of a race car is to use rear spoilers. This study by using ANSYS FLUENT numerically investigated the effect of the spoiler shape and setting angle on the aerodynamic characteristics of a race car and then it was validated by conducting wind tunnel experiment. Lift and drag coefficient of NACA0012, NACA4412, and S1223 are determined in Reynold’s number of 2×105 as an airfoil and as spoiler on ERC model which is a conceptual car model inspired by Porsche 911. It was found that ERC model with spoiler would have better aerodynamic efficiency compared to ERC model without spoiler. Also, S1223 at -6 degrees was identified as the optimized configuration as it generates the highest downforce. Even though the drag coefficient at this setting angle is slightly higher, but in terms of stability and handling IT is at its best. Overall, this study would help car manufacturers, for racing and commercial purposes, to have a better insight into the effect of spoiler configuration on the aerodynamic performance of cars. Hence, the stability, handling, and efficiency of the cars can be further improved by selecting the suitable spoiler configuration.

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CFD analysis of the aerodynamic characteristics of biconvex airfoil at compressible and high Mach numbers flow

SN Applied Sciences ◽

10.1007/s42452-019-1334-2 ◽

2019 ◽

Vol 1 (10) ◽

Author(s):

Ebrahim Hosseini

Keyword(s):

Aerodynamic Characteristics ◽

Cfd Analysis ◽

Mach Numbers ◽

High Mach

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Aerodynamic performance improvement of WIG aircraft

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-05-2015-0139 ◽

2017 ◽

Vol 89 (1) ◽

pp. 120-132 ◽

Cited By ~ 3

Author(s):

Mojtaba Tahani ◽

Mehran Masdari ◽

Ali Bargestan

Keyword(s):

Dihedral Angle ◽

Twist Angle ◽

Lift Coefficient ◽

Ground Effect ◽

Aerodynamic Characteristics ◽

Aerodynamic Performance ◽

Sweep Angle ◽

Content Type ◽

Ground Clearance ◽

Geometrical Characteristics

Purpose This paper aims to investigate the aerodynamic characteristics as well as static stability of wing-in-ground effect aircraft. The effect of geometrical characteristics, namely, twist angle, dihedral angle, sweep angle and taper ratio are examined. Design/methodology/approach A three-dimensional computational fluid dynamic code is developed to investigate the aerodynamic characteristics of the effect. The turbulent model is utilized for characterization of flow over wing surface. Findings The numerical results show that the maximum change of the drag coefficient depends on the angle of attack, twist angle and ground clearance, in a decreasing order. Also, it is found that the lift coefficient increases as the ground clearance, twist angle and dihedral angle decrease. On the other hand, the sweep angle does not have a significant effect on the lift coefficient for the considered wing section and Reynolds number. Also, as the aerodynamic characteristics increase, the taper ratio befits in trailing state. Practical implications To design an aircraft, the effect of each design parameter needs to be estimated. For this purpose, the sensitivity analysis is used. In this paper, the influence of all parameter against each other including ground clearance, angle of attack, twist angle, dihedral angle and sweep angle for the NACA 6409 are investigated. Originality/value As a summary, the contribution of this paper is to predict the aerodynamic performance for the cruise condition. In this study, the sensitivity of the design parameter on aerodynamic performance can be estimated and the effect of geometrical characteristics has been investigated in detail. Also, the best lift to drag coefficient for the NACA 6409 wing section specifies and two types of taper ratios in ground effect are compared.

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Surface suction on aerofoil aerodynamic characteristics at transonic speeds

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1243/0954410981532324 ◽

1998 ◽

Vol 212 (5) ◽

pp. 339-351 ◽

Cited By ~ 5

Author(s):

N Qin ◽

Y Zhu ◽

D I A Poll

Keyword(s):

Flow Control ◽

Numerical Study ◽

Active Flow Control ◽

Effective Means ◽

Active Surface ◽

Aerodynamic Characteristics ◽

Aerodynamic Performance ◽

Surface Suction ◽

Lift And Drag ◽

Active Flow

This paper presents a numerical study of the effects of an active flow control through surface suction on shock boundary layer interactions over transonic aerofoils. Two different aerofoils were studied. Firstly, for the purpose of validation, an NACA64A010 aerofoil with a trailing edge flap was investigated and the numerical results were compared with experimental data with and without suction for surface pressure distributions and lift and drag coefficients. Grid sensitivity has also been studied regarding the numerical accuracy. The second geometry was an RAE9647 aerofoil, which was designed for superior aerodynamic performance when applied to a helicopter rotor blade. An active surface was used to prevent or alleviate shock-induced separation. The suction strength and location were varied to determine the effect on aerodynamic performance and to provide an effective means of suppressing undesirable flow features. In both cases, increases in both lift and drag were observed when surface suction was applied. However, the benefit of suction appeared in the form of a substantial increase in the lift-drag ratio. It was also found that the shock location and strength are very sensitive to the suction location and strength. Two different mechanisms for active flow control over transonic aerofoils are discussed.

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Computational Study Of Curved Underbody Diffusers

E3S Web of Conferences ◽

10.1051/e3sconf/201912810002 ◽

2019 ◽

Vol 128 ◽

pp. 10002

Author(s):

Angel Huminic ◽

Gabriela Huminic

Keyword(s):

Computational Study ◽

Aerodynamic Characteristics ◽

Passenger Car ◽

Lift And Drag ◽

Underbody Diffuser ◽

Ahmed Body

This paper presents new results concerning the aerodynamics of the Ahmed body fitted with a non-flat underbody diffuser. As in previous investigations performed, the angle and the length of the diffuser are the parameters systematically varied within ranges relevant for a hatchback passenger car. Coefficients of lift and drag are compared with the values obtained for the flat underbody diffuser, and the results reveal significant improvements concerning aerodynamic characteristics of body.

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Numerical study of geometric morphing wings of the 1303 UCAV

The Aeronautical Journal ◽

10.1017/aer.2021.15 ◽

2021 ◽

pp. 1-17

Author(s):

B. Nugroho ◽

J. Brett ◽

B.T. Bleckly ◽

R.C. Chin

Keyword(s):

Flight Control ◽

Numerical Study ◽

Aerodynamic Characteristics ◽

Morphing Wing ◽

Rolling Moment ◽

Wide Range ◽

Morphing Wings ◽

Wing Geometry ◽

Lift And Drag ◽

Wing Morphing

ABSTRACT Unmanned Combat Aerial Vehicles (UCAVs) are believed by many to be the future of aerial strike/reconnaissance capability. This belief led to the design of the UCAV 1303 by Boeing Phantom Works and the US Airforce Lab in the late 1990s. Because UCAV 1303 is expected to take on a wide range of mission roles that are risky for human pilots, it needs to be highly adaptable. Geometric morphing can provide such adaptability and allow the UCAV 1303 to optimise its physical feature mid-flight to increase the lift-to-drag ratio, manoeuvrability, cruise distance, flight control, etc. This capability is extremely beneficial since it will enable the UCAV to reconcile conflicting mission requirements (e.g. loiter and dash within the same mission). In this study, we conduct several modifications to the wing geometry of UCAV 1303 via Computational Fluid Dynamics (CFD) to analyse its aerodynamic characteristics produced by a range of different wing geometric morphs. Here we look into two specific geometric morphing wings: linear twists on one of the wings and linear twists at both wings (wash-in and washout). A baseline CFD of the UCAV 1303 without any wing morphing is validated against published wind tunnel data, before proceeding to simulate morphing wing configurations. The results show that geometric morphing wing influences the UCAV-1303 aerodynamic characteristics significantly, improving the coefficient of lift and drag, pitching moment and rolling moment.

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