Combined Forced and Free Convection for Co-Axial Horizontal Cylinders.
Abstract
Experimental results and their correlation are presented for the combined forced and free convection in the annular region of horizontal co-axial cylinder. Results demonstrate that the heat transferred from the inner cylinder can be correlated on the basis of diameter ratio, Grashoff, Reynolds, and Prandtl numbers. Nusselt numbers for carbon dioxide do not correlate with air and argon according to the Prandtl number but, are ordered inversely with their viscosities. Free convection Nusselt numbers increase with the diameter ratio whereas those for forced convection decrease. Thermal radiation produces an apparent increase in the Nusselt number for all Grashoff and Reynolds number. A critical Reynolds number exists for which the heat transfer becomes independent of the influence of free convection. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1972
- Accession Number
- AD0754017
Entities
People
- Frank C. Jarvis
- Kenneth R. Cramer
Organizations
- Air Force Research Laboratory