Accession Number:

AD0700062

Title:

HYPERSONIC WIND TUNNEL MEASUREMENTS OF ROLL DAMPING DERIVATIVES FOR CONES

Descriptive Note:

Corporate Author:

AEROSPACE RESEARCH LABS WRIGHT-PATTERSON AFB OH

Personal Author(s):

• Walchner, Otto
• Sawyer, Frank M.
• Durham, Thomas A.

Report Date:

1969-10-01

Pagination or Media Count:

45.0

Abstract:

The roll damping derivatives for a 10 deg cone with various nose bluntness ratios were measured at Mach 12.7 and 14.2 Re 250,000, in axial flow and at angles of attack up to plus or minus 8 degrees. An air bearing, supporting the model with freedom in roll, was designed specifically for these tests. The bearing performance is described in detail. The measured derivatives compare very favorably with Quinns laminar roll damping theory for blunted cones in axial flow. A moderate decrease of the magnitude of the derivatives results from blunting the nose. At angles of attack, this blunt nose effect diminishes and the blunt cone derivatives approach the sharp cone values with increasing angle of attack. Experimental difficulties at angles of attack were traced to possible free stream deficiencies and were overcome by increasing the model roll rate.

Descriptors:

• *CONICAL BODIES
• *ROLL
• MODEL TESTS
• NOSE CONES
• BLUNT BODIES
• WIND TUNNEL MODELS
• ANGLE OF ATTACK
• DAMPING
• HYPERSONIC CHARACTERISTICS

Subject Categories:

• Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE