Turbulence Instrumentation for Stratospheric Airships
Abstract
Both commercial and high altitude aircraft such as the U-2 may encounter turbulence in flight. The turbulence seems to be associated with buoyancy waves generated by flow over mountains that can break into turbulence. The exact nature of the wave breaking is not fully understood, and forecast models need to be examined to determine their ability to forecast turbulence. The High Altitude Airship is designed to investigate these phenomena. In order to sense atmospheric turbulence at altitudes of the expected flight of the High Altitude Airship of around 65,000ft, a prototype ionic anemometer was constructed. The instrument was checked out in flow at one atmosphere using an available flow channel. It was then checked in a Bell Jar at the density conditions expected at high altitude. For the remaining flow test at high altitudes, it was decided to construct an inexpensive wind tunnel which could operate under vacuum at near target altitudes. This report documents the design and checkout of the tunnel, and contains recommendations for further work.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2007
- Accession Number
- ADA488982
Entities
People
- Brent E. Barbeau
- George Y. Jumper
- Kris D. Robinson
- Lawrence M. Saupe
- Mark L. Duell
Organizations
- Air Force Research Laboratory