Author: Benferd L. SchillingPublisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 66
Book Description
Calculated Wind-tunnel-boundary Lift-interference Factors for Rectangular Perforated Test Sections
Author: Benferd L. SchillingPublisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 66
Book Description
Calculated Wind-tunnel-boundary Lift-interference Factors for Rectangular Perforated Test Sections
Author: Benferd L. SchillingA Numerical Method of Calculating the Boundary-induced Interference in Slotted of Perforated Wind Tunnels of Rectangular Cross Section
Author: James D. KellerPublisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 26
Book Description
A numerical method is presented for calculating the boundary-induced interference at subsonic speeds in wind tunnels of rectangular cross section with slotted or perforated walls. The slot width or wall porosity can vary throughout the test section. The interference can be computed at any point in the test section. The model can be any configuration and can be located anywhere in the test section. Several examples are given, and comparison is made with other methods were available.
Approximation of the Spanwise Distribution of Wind-tunnel-boundary Interference on Lift of Wings in Rectangular Perforated-wall Test Sections
Author: Ray H. WrightPublisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 42
Book Description
An approximation method has been developed for calculating the spanwise distribution of wind-tunnel-boundary upwash interference on lift of wings in rectangular perforated-wall test sections. This method is applied to square test sections with an assumed effective permeability constant of 0.6. A problem of considerable difficulty in practical application of the method presented is the estimation of an effective permeability constant. Because of the variation of the upwash interference with Mach number and of the influence of boundary layer on the effective permeability factor, the boundary interference in a perforated-wall wind-tunnel test section at high subsonic Mach numbers is likely to be of the nature of that in an open-throat tunnel.
Numerical Calculation of Boundary-induced Interference in Slotted Or Perforated Wind Tunnels Including Viscous Effects in Slots
Author: James D. KellerPublisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 26
Book Description
A numerical method is presented for calculating the incompressible boundary-induced interference in wind tunnels of rectangular cross section with slotted or perforated walls. The method includes a wall representation which is capable of satisfying a generalized homogeneous boundary condition including the effects of viscosity within the slots. The effects of viscosity in the slots are found to be very significant. The method allows for a variation in the boundary conditions along the tunnel walls. The model can be any configuration and can be located anywhere in the test section. The interference can be computed at any point in the test section.
Analytical Study of Ventilated Wind Tunnel Boundary Interference on V/STOL Models Including Wake Curvature and Decay Effects
Author: E. M. KraftPublisher:
ISBN:
Category : Short take-off and landing aircraft
Languages : en
Pages : 74
Book Description
The wind tunnel boundary interference on a V/STOL model is calculated in a rectangular test section with solid vertical walls and ventilated (perforated or slotted) horizontal walls. The interference is found by applying the small perturbation theory of an incompressible fluid to the boundary value problem. The theory uses an image method in addition to Fourier transforms with an equivalent homogeneous boundary condition on the ventilated wall. The mathematical representation of the V/STOL model accounts for the curvature and decay of the wake. The assumption of a constant wake strength produces a paradox in that the maximum value of the interference factors increases as the initial jet velocity decreases. The most significant aspect of the analysis shows that nonlinear cross-flow effects at the tunnel boundary are important in the V/STOL case, and a quasi-linear approximation to these effects is introduced into the solution providing good agreement with experimental data.
NASA Technical Note
Author: NASA Technical Report
Author: United States. National Aeronautics and Space AdministrationPublisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 946
Book Description
Monthly Catalogue, United States Public Documents
Author: Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1250
Book Description
Author: