Cover of: A study of methods to increase the lift of supersonic airfoils at low speeds | Albert David Pollock

A study of methods to increase the lift of supersonic airfoils at low speeds

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by
California Institute of Technology
Aerona
Statementby A.D. Pollock and F.F. Reck
ContributionsReck, Floyd Francis
ID Numbers
Open LibraryOL24723238M

The companion book Airfoils at Low Speeds (by Selig, Donovan and Fraser), which was first published as SoarTech 8 in The book presents the results of wind-tunnel tests conducted at Princeton University on over 60 airfoils for model aircraft (mostly radio controlled sailplanes), and it also introduces the.

ASTUDYOFMETHODSTOIXHFJ THBLIFTOFSUPERSONICAIRFOILSAT Theais *y A.D.^ollock,Jr.,U.S.N. and ,U.S.a*. This thesis presents a study of the problem of improving the lift characteristics of a supersonic wing at low speeds.

Trailing edge split flaps, nose flaps, and boundary layer control were investigated singularly and together using the optimum configuration of each.

Results indicate that the nose flap has an appreciable effect on preventing separation and thus increasing the : Albert David Pollock, Floyd Francis Reck.

Description A study of methods to increase the lift of supersonic airfoils at low speeds FB2

A study of methods to increase the lift of supersonic. This thesis presents a study of the problem of improving the lift characteristics of a supersonic wing at low speeds. Trailing edge split flaps, nose flaps, and boundary layer control were investigated singularly and together using the optimum configuration of s indicate that the nose flap has an appreciable effect on preventing separation and thus increasing the : Albert David Pollock, Floyd Francis Reck.

Abstract. This thesis presents a study of the problem of improving the lift characteristics of a supersonic wing at low speeds. Trailing edge split flaps, nose flaps, and boundary layer control were investigated singularly and together using the optimum configuration of each.\ud \ud Results indicate that the nose flap has an appreciable effect on preventing separation and thus increasing the lift.

A study of methods to increase the lift of supersonic airfoils at low speeds. This thesis presents a study of the problem of improving the lift characteristics of a supersonic wing at low speeds.

Trailing edge split flaps, nose flaps, and boundary layer control were investigated singularly and together using the optimum configuration of. These methods are applied to the calculation of performance of several types of three-dimensional supersonic airfoils; in particular, the drag at zero lift.

problem of improving the lift characteristics of supersonic airfoil at low speeds. Pollok, et. al, [2] presented a study of methods to increase the lift of a double wedge supersonic airfoils at low speeds.

Their results indicate that the nose flap had an appreciable effect. A supersonic transport (SST) is a civilian supersonic aircraft designed to transport passengers at speeds greater than the speed of date, the only SSTs to see regular service have been Concorde and the Tupolev TuThe last passenger flight of the Tu was in June and it was last flown in by de's last commercial flight was in October.

upper surface pressure is taken equal to the vacuum value. We can see that at low speeds the lift is generated on the upper surface, while at high speed the lift is almost completely generated on the lower surface. This will be important when designing hypersonic vehicles.

C p M 25 deg. Advanced versions of the method exploited such modern computing techniques as fast Fourier transforms [18]. If aerodynamic design involved only two-dimensional flows at low speeds, a design method based on conformal transformation would be a good choice.

However, the technique cannot be extended to three-dimensional or high-speed flows. Aerodynamics, from Greek ἀήρ aero (air) + δυναμική (dynamics), is the study of motion of air, particularly as interaction with a solid object, such as an airplane wing.

It is a sub-field of fluid dynamics and gas dynamics, and many aspects of aerodynamics theory are common to these term aerodynamics is often used synonymously with gas dynamics, the difference.

Generally such transonic airfoils and also the supersonic airfoils have a low camber to reduce drag divergence. Modern aircraft wings may have different airfoil sections along the wing span, each one optimized for the conditions in each section of the wing.

Details A study of methods to increase the lift of supersonic airfoils at low speeds FB2

Movable high-lift devices, flaps and sometimes slats, are fitted to airfoils on almost. Summary. In this study exemplary results on the influence of two fundamental unsteady parameters, the reduced frequency k and the non-dimensional pitching rate α +, on the transition from a steady to an unsteady flow field around the reference airfoil BAC3–11/RES/30/21 are presented using experimental and numerical tools used are described and.

A number of references have been included to allow the reader to study both the older NACA literature and the new airfoil design ideas. Taken together, this literature provides a means of obtaining a rather complete understanding of the ways in which airfoils can be shaped to obtain desired performance characteristics.

So, to increase the performance of airfoil at low Reynolds number, there are some methods involved like airfoil shaping, boundary layer control and also by increasing the flow speeds.

Airfoils and Wings Introduction Transonic flow occurs when there is mixed sub- and supersonic local flow in the same flowfield (typically with freestream Mach numbers from M = or to ).

Usually the supersonic region of the flow is terminated by a shock wave, allowing the flow to slow down to subsonic speeds.

Download A study of methods to increase the lift of supersonic airfoils at low speeds FB2

the momentum deflcit method To account for spanwise drag variations at low Reynolds numbers,18 the drag was obtained from an average of eight equidistant wake surveys over the center of the model so that a in.

wide span was covered. The overall uncertainty in both the lift and drag measurements was estimated at %,17 All lift and drag measurements. An overall increase in the lift-to-drag ratio of 9% is achieved at Mach and 6° angle of attack. In another study [Borovoy et al.,], the flow and heat transfer on the fins attached to the.

Start studying Science of Flight: Chapter 1, Lessons 1,2, Learn vocabulary, terms, and more with flashcards, games, and other study tools. Among the above aerodynamic configurations, the Busemann biplane may be promising due to the characteristics of low drag and low boom [12,13].It is a classic aerodynamic concept that is introduced by Adolf Busemann in [].It contains two same isosceles-triangle airfoils, as shown in Fig.

the design condition, the pressure acting on the front and the latter halves of. The supersonic aerodynamics at play here is too in depth for this discussion; suffice to say that this thin airfoil is built for speed and not to produce large amounts of lift at low speed.

Let’s look at all three airfoils next to one another before diving into the airfoil engineering principles used to select each one for the aircraft. To understand how camber affects performance factors such as lift and lift to drag ratio, XFOIL is used to study thin (3% thickness to chord ratio) airfoils at a low Reynolds number ofThe performance of the optimized designs shows several positive characteristics as compared to single element airfoils, such as a high stall angle, high lift below stall, low roughness sensitivity.

Configuration Aerodynamics 7/31/16 Figure The SR The XB The XB is shown in Figures and The airplane was intended to be a Mach 3 intercontinental bomber. However, the successful development of ICBMs meant there was no.

Thin swept wings of low aspect ratio are part of the aerodynamic ingredients of a low-drag supersonic aircraft but, at the same time, yield an aircaft with a relatively low maximum lift-drag ratio at subsonic speeds, as well as certain undesirable handling characteristics in the low-speed, high-angle-of-attack regime.

Aerodynamics is a branch of dynamics concerned with the study of the motion of is a sub-field of fluid and gas dynamics, and the term "aerodynamics" is often used when referring to fluid dynamics. Early records of fundamental aerodynamics concepts date back to the work of Aristotle and Archimedes in the 2nd and 3rd centuries BC, but efforts to develop a quantitative theory of.

increase range, payload, and altitude capabilities as well as lower fuel requirements, skin tempera-ture, and therefore the overall cost. A parametric study to predict the extent of laminar flow for finite wings at supersonic speeds was conducted using a computational fluid dynamics (CFD) code cou-pled with a boundary layer stability code.

Summary of Low-Speed Airfoil Data, Volume 2 is the second book in the se­ ries that documents the ongoing work of the University of Illinois at Urbana­ Champaign Low-Speed Airfoil Tests (UIUC LSATs) program.

As described in the first volume, most of the airfoils. The F call sign 'Raptor'. Notice the shape of the wings crafted for better maneuverability at supersonic speeds. The wings of the carrier A have been designed for subsonic high lift characteristics.

Two different scenarios using same theory for their working! Body Governing The Nomenclature for Airfoils.the lift, which is that at low Mach numbers, an increase in swept angle would degrade the performance of the wing; however at higher Mach numbers, the increase in swept angle has a positive effect.

The reason for such behavior still requires further investigation. The relative thickness and airfoil shape were also found to have.Generally, adding camber will increase the maximum lift coefficient. Since the lift curve slope is essentially fixed, this means stall will occur at a higher angle of attack.

Botag4 April (UTC) Defining the Lift Coefficient. I propose more effort be applied into defining what the lift coefficient is, why it is used, and how it is used.