Accession Number:

ADA027497

Title:

Pitot Pressure Profile Measurement at the Exit of Very Small Nozzles

Descriptive Note:

Interim rept.

Corporate Author:

AEROSPACE CORP EL SEGUNDO CA AEROPHYSICS LAB

Personal Author(s):

• Varwig, Robert L.
• Durran, Donald A.
• Liu, Shaowen W.

Report Date:

1976-06-04

Pagination or Media Count:

22.0

Abstract:

Pitot pressure profile measurements at the exit plane of a nozzle are used to characterize the flow properties of nozzles. For very small nozzles, where the boundary layer is a singificant part of the nozzle, the pitot pressure profile obtained when the probe is traversed across the nozzle exit displays peculiar properties. Close to the nozzle exist, at the edge of the nozzle, there are sharp peaks in the profile, and there is a lower pressure on the centerline than closer to the wall. The former effect is attributed to flow separation caused by the traversing probe, which is large relative to the scale of the flow nonuniformities, as in the case of a forward facing step. The latter effect is caused by the boundary layer, which changes the effective contour of the nozzle wall. In the 0.060-in.-diam conical nozzle of this study, the boundary layer changed the shape from conical to that approximating the first third of a Mach 6 contoured nozzle.

Descriptors:

• *BOUNDARY LAYER
• *PRESSURE
• *BOUNDARY LAYER FLOW
• *WIND TUNNEL NOZZLES
• AERODYNAMIC CONFIGURATIONS
• MEASUREMENT
• PROBES
• INTERACTIONS
• PROFILES
• CONICAL BODIES
• PITOT TUBES
• CONTOURS

Subject Categories:

• Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE