Pressure Drop and Heat Transfer in a Duct With Triangular Cross Section
| Autor: | E. R. G. Eckert, Thomas F. Irvine |
|---|---|
| Rok vydání: | 1960 |
| Předmět: |
Pressure drop
Materials science Turbulence Mechanical Engineering Reynolds number Thermodynamics Laminar flow Mechanics Condensed Matter Physics Physics::Fluid Dynamics symbols.namesake Mechanics of Materials Heat generation Heat transfer symbols General Materials Science Hydraulic diameter Duct (flow) |
| Zdroj: | Journal of Heat Transfer. 82:125-136 |
| ISSN: | 1528-8943 0022-1481 |
| Popis: | Friction factors have been measured for a duct whose cross section has the shape of an isosceles triangle with a side ratio 5 to 1 in the fully developed flow region for laminar, transitional, and turbulent conditions. In addition, local and average heat-transfer coefficients and the temperature field in the duct wall have been determined for the condition of constant heat generation per unit volume of the duct walls. Friction factors in laminar flow agreed well with analytical predictions. In the turbulent flow range they were by 20 per cent lower than values calculated from relations for a round tube with the use of the “hydraulic diameter.” Heat-transfer coefficients averaged over the circumference of the duct were only half as large as values calculated from round tube relations in the Reynolds number range from 4300 to 24,000. The measurements also revealed that thermal starting lengths were in excess of 100 diameters. In round tubes a length of 10 to 20 diameters has been found sufficient to develop the temperature field. |
| Databáze: | OpenAIRE |
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