Ground Wash Flow over Deflecting Walls. Report 1. Feasibility Study,
Abstract
The report describes an investigation conducted to determine by visual means the flow pattern of air as it moves over deflectors of various sizes and shapes. Knowledge of these flow patterns could be applied to the control of the ground wash blast from various tactical missiles and air vehicles to provide safe operational areas with the minimum of ground surface protection that will alleviate dust cloud formation. Vertical walls have been used to reduce extended ground wash effects and, in turn, to decrease the size of the area requiring protection during several missile launches at the White Sands Missile Range, New Mexico. Tests were conducted utilizing a spherical mirror and photographic equipment to obtain schlieren photographs of airflow paths over the various deflectors in order to choose for further study those that would direct the high-velocity ground wash up above the ground surface and out of the aircraft operational area. The investigation had no specific vehicle problem as its primary study. Because it was a small-scale study, only qualitative data were obtained. The schlieren study indicated that the properly shaped deflector will substantially reduce the size of the area of protection required for dust alleviation at a vertical takeoff air vehicle operational site, with a vertical or nearly vertical wall being the optimum shape. The study will be extended to larger scales to determine the boundary layer velocities and changes in location of the flow pattern as flow passes over objects such as sandbags, vertically placed landing mat panels, timber fences, windrowed soils, etc. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1969
- Accession Number
- AD0731199
Entities
People
- Grady W. Leese