A STUDY OF THE WALL BOUNDARY CONDITION AND MICROSCOPIC FLUCTUATIONS IN LAMINAR PIPE FLOW BY TRACER PHOTOGRAPHY,
Abstract
A high precision, high resolution tracer technique was used to study low noise, steady laminar air flow in a 1-1/2 inch by 1/2 inch rectangular pipe. The tracers were sub-micron size cigarette smoke particles which were injected into the flow and illuminated by chopping light from a carbon arc lamp which allowed their trajectories to be photographed. Photography on moving film in the image plane of the microscope camera permitted extension of the flow regions which could be examined and increased both the accuracy and duration of the observations. The flows investigated had velocities at the middle of the tube of 0.023, 0.43, 1.2 and 6.2 meters per second which correspond to pipe Reynolds numbers of 16, 300, 840 and 4300. A velocity profile for the lowest flow speed, plotted from the floor to the midstream (7100 microns from floor) was parabolic in shape within the 2.5% constancy of the flow over times the order of hours. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1963
- Accession Number
- AD0423690
Entities
People
- Richard M. Elrick Ii.
Organizations
- Lehigh University