AN EXPERIMENTAL STUDY OF THE EFFECTS OF BOUNDARY LAYER THICKNESS AND VELOCITY PROFILE ON THE PRESSURE DISTRIBUTIONS OF OBJECTS IMMERSED IN THE BOUNDARY LAYER
Abstract
Pressure distributions were measured on six models in three different boundary layer conditions. Two hemispheres, two semicylinders, and two half bodies of revolution were used in the tests. The range of Reynolds numbers for the hemispheres and semicylinders was form 0.6 x 60,000 to 1.6 x 160,000 (based on diameter and free stream velocity). The boundary layer thicknesses ranged from about one-half to twice the characteristic model dimension. The effect of increasing boundary layer thickness (or momentum thickness) was a reduction in the positive and negative ordinates of the pressure distributions. The pressures on three-dimensional models were approximately the same at a given longitudinal station, although there may have been a small reduction in pressures close to the wall on which the object was mounted. No simple relationship could be found for relating the changes in pressure distribution to changes in velocity profile or boundary layer thickness, however a data correlation was obtained relating the minimum pressure coefficient for a particular boundary layer condition to the minimum pressure coefficient measured in a uniform flow.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1965
- Accession Number
- AD0463575
Entities
People
- Clifford L. Sayre Jr.
Organizations
- University of Maryland