Accession Number:

AD0429469

Title:

TUNNEL WALL INTERFERENCE EFFECTS ON THE DRAG AND PITCHING MOMENT OF AN AXISYMMETRIC BODY,

Descriptive Note:

Corporate Author:

PENNSYLVANIA STATE UNIV UNIVERSITY PARK ORDNANCE RESEARCH LAB

Personal Author(s):

Report Date:

1964-01-14

Pagination or Media Count:

211.0

Abstract:

A method is developed for the prediction of the interference effects of a wind or water tunnel wall on the drag and pitching moment of a three dimensional model. The investigation is divided into two parts. The first part develops a theory for the prediction of the effect of tunnel wall deviations on the drag of the model, while the second part develops a theory for the effect of the tunnel wall on the pitching moment of the model. In determining the effects of tunnel wall deviations on model drag, the investigation is limited to a non-viscous fluid, potential flow, and an axisymmetric deviation. A small deviation is first considered and the magnitude of interference effect is found to be proportional to the thickness of the deviation and the cube of the distance from the deviation. A method is also developed which can be used to determine the interference effect of any size deviation. This second method is used to determine the effect the tunnel nozzle has on the measured drag of a model. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE