Record Details
Turbulent heat transfer in annuli at large diameter ratios
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Turbulent heat transfer in annuli at large diameter ratios |
| Names |
Unzicker, William Frank
(creator) Knudsen J. G. (advisor) |
| Date Issued | 1966-07-25 (iso8601) |
| Note | Graduation date: 1967 |
| Abstract | Heat transfer from the inner wall of an annulus to subcooled water in turbulent parallel flow was studied. The inner core of the annulus consisted of wires varying from 0.0019 to 0.0197 inch in diameter. The outer tube consisted of a 1.01 inch diameter glass tube 24 inches long. Diameter ratios therefore varied from 530:1 to 51:1. The water velocity varied from 1.8 to 13.5 feet per second. Rectified alternating current was supplied to the wires. The current, wire surface area, wire resistance, and bulk water temperature were measured and from this data the average convective heat transfer coefficient calculated. The heat transfer coefficient varied from 1840 to 4990 BTU /hr. ft²[superscript .]F for the 0.0197 inch diameter wire to 7210 to 13000 BTU /hr. ft. ²[superscript .]F for the 0.0019 inch diameter wire. The data agreed well with that of Mueller who had worked with air in annuli of large diameter ratios. The data correlated when plotted as N[subscript Nu]/N[subscript Prf]¹[superscript /]³ versus N[subscript Re] when the equivalent diameter was based on experimentally determined radii of maximum velocity in turbulent annular flow. Over the range of operating conditions studied the heat transfer coefficients were considerably lower than predicted by the usual empirical equations. |
| Genre | Thesis/Dissertation |
| Topic | Heat -- Transmission |
| Identifier | http://hdl.handle.net/1957/47335 |
