Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Issues Relating to Laminar Flow Control on the Leading-edge of Swept Wings
Author: Boundary Layer and Flow Control
Author: G. V. LachmannPublisher: Elsevier
ISBN: 1483226662
Category : Technology & Engineering
Languages : en
Pages : 768
Book Description
Boundary Layer and Flow Control: Its Principles and Application, Volume 2 focuses on the layer of fluid in the immediate area of a bounding surface where the effects of viscosity are substantial. This book is organized into two main topics—boundary layer control for low drag, and shock-induced separation and its prevention by design and boundary layer control. It specifically discusses the nature of transition, effect of two-dimensional and isolated roughness on laminar flow, and progress in the design of low drag aerofoils. The onset of separation effects for aerofoils and wings, shock-induced separation for laminar boundary layers, and shock-induced separation for laminar boundary layers are also deliberated. This volume is recommended to physicists and specialists interested in boundary layer and flow control.
Computations of Laminar Flow Control on Swept Wings as a Companion to Flight Test Research
Author: Richard G. RhodesPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The high cost of energy has resulted in a renewed interest in the study of reducing skin-friction drag in aeronautical applications. Laminar Flow Control (LFC) refers to any technique which alters the basic-state flow-field to delay transition from laminar to turbulent flow. Achieving fully laminar flow over a civilian transport wing will significantly reduce drag and fuel costs while increasing range and performance. Boundary-layer suction has proven to be an effective means of achieving laminar flow over an aircraft wing as demonstrated with the Northrop X-21 program; however, even with the savings in fuel, the high manufacturing and maintenance costs have discouraged the use of this technology. Recent work using threedimensional (3-D) spanwise-periodic distributed roughness elements (DREs) has shown great promise as a means of controlling the crossflow instability responsible for transition over a swept wing without the need for a complex suction system. The Texas A.
An Experimental Investigation of Boundary-layer Control for Drag Reduction of a Swept-wing Section at Low Speed and High Reynolds Numbers
Author: Donald E. GaultPublisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 22
Book Description
Separation Ahead of Controls on Swept Wings
Author: Kaufman Louis G. (II)Publisher:
ISBN:
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 60
Book Description
Shock-induced flow-separation ahead of trailing edge controls on swept wings is investigated with emphasis on the effects of boundary layer transition on the location and shape of the separation line. Experimental results were obtained by using forward facing steps mounted on swept-leading-edge flat-plate wing models in the ARL Mach 6 Tunnel for model running length Reynolds numbers varying from 0.9 to 33 million. The data support qualitatively a proposed, strip-type method for estimating, the extent and shape of the three dimensional region of separated flow ahead of controls on swept wings. (Author).
Feasibility and Benefits of Laminar Flow Control on Supersonic Cruise Airplanes
Author: Effects of Sweep Angle on the Boundary-layer Stability Characteristics of an Untapered Wing at Low Speeds
Author: Frederick W. BoltzPublisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 86
Book Description
Flow Control Over Sharp-edged Wings
Author: Jose RullanPublisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 136
Book Description
Wings swept by 30 to 40 degrees with sharp leading edges are today very common on flghter aircraft. There is very little work devoted to the understanding of the aerodynamics of such wings. The problem is that such wings may be able to sustain attached flow, even if their tip vortices are broken down, or stall like two-dimensional wings. The aerodynamics of such wings were studied and investigated experimentally. Pressure distributions and velocity fields were obtained in a wind tunnel and a water tunnel. The effectiveness of leading-edge control of the flow over such wings was explored. Oscillating mini-flaps and pulsed jets along the leading edge were employed. The results indicate that two-D-like vortices are periodically generated and shed. It was also discovered that an underline feature of the flow, a streamwise vortex is periodically activated, penetrating the separated flow, eventually emerging downstream of the trailing edge of the wing. The results indicate that significant increases in tilt can be achieved in the average, by managing the development of streamwise and spanwise vortices. The technique is effective in the range of angles of attack of 10 to 20 degrees, for which the uncontrolled flow is stalled.
Summary of Laminar Flow Control Techniques for Aircraft
Author: Philip P. AntonatosPublisher:
ISBN:
Category : Laminar flow
Languages : en
Pages : 44
Book Description
Author: