Contrails
The goal of the Contrails project is to help preserve and disseminate the technical record of 20th century aerospace research, highlighting in particular the research endeavors of the Illinois Tech community.

Analytical Study of Ventilated Wind Tunnel Boundary Interference on V/STOL Models Including Wake Curvature and Decay Effects

Report Number: AEDC TR 74-51
Author(s): E. M. Kraft
Corporate Author: ARO, Inc.
Laboratory: Propulsion Wind Tunnel Facility
Date of Publication: 1974-11
Pages: 59
Contract: None Given
Contract: `
Project: None Given
AD Number: ADA000922

Abstract:
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. It is indicated that a realistic representation of the wake decay may be as significant as the wake curvature in assessing interference on pitching moment, tail forces, or blockage effects. 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.

Download this report

(PDF, 0.84 MB, 59 pages)

Other options for obtaining this report

Via the Defense Technical Information Center (DTIC):
A record for this report, and possibly a full-image download of the report, exists at DTIC

Via National Technical Information Service:
This report may have been digitized and made freely available for public download, or made publicly available for purchase by the National Technical Information Service through their online database, the National Technical Reports Library

Indications of Public Availability
No digitial image of an index entry indicating public availability is currently available
There has been no verification of an indication of public availability from an inside cover statement