Accession Number:

ADA202028

Title:

Flow Visualization of the Airwake Around a Model of a DD-963 Class Destroyer in a Simulated Atmospheric Boundary Layer

Descriptive Note:

Master's thesis

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s):

Report Date:

1988-09-01

Pagination or Media Count:

57.0

Abstract:

This study is part of a longer-term project to map the airwakes of model ships for scaling to full size and use in helicopter simulators to provide an alternative to at-sea dynamic interface testing utilizing the Naval Postgraduate School flow visualization tunnel modified to simulate the open ocean atmospheric boundary layer. A detailed analysis has been made of the airflow near the flight deck of the DD-963 in a stationary mode, using helium bubble, smoke, photographic and video equipment. The results show that the primary variable in the airwake is the yaw angle of the ship pitch and roll having a lesser influence. Some highly complex flow patterns have been observed above the flight deck. For example, at zero degrees yaw, the airflow along the center line of the ship flows over the hangar and splits the higher level of th4 flow continues aft and the lower level proceeds downwards towards the deck and turns back towards the hangar this flow further splits, heading towards port and starboard, curls upward almost to the hangar roof level and finally flows downwind in two streams along paths close to both sides of the ship. This pattern becomes displaced to one side of the ship or other, depending on the yaw angle. Keywords Flow visualization, Simulated atmospheric boundary layer, Helium bubble flow visualization, Smoke flow visualization, Spruance class destroyer, Military theses. kt

Subject Categories:

  • Military Aircraft Operations
  • Helicopters
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE