Turbulent Free Convection Heat Transfer to Drag-Reducing Fluids From Arbitrary Geometric Configurations

1992 ◽  
Vol 114 (1) ◽  
pp. 127-134 ◽  
Author(s):  
A. Nakayama ◽  
A. V. Shenoy
Keyword(s):  
Heat Transfer ◽  
Free Convection ◽  
Convection Heat Transfer ◽  
Convection Heat ◽  
Streamwise Direction ◽  
Geometric Configurations ◽  
Free Convection Heat ◽  
Solution Methodology ◽  
Horizontal Circular Cylinder ◽  
Arbitrary Fashion

The problem of turbulent free convection heat transfer from curved surfaces to drag-reducing fluids has been investigated using the Nakayama-Koyama solution methodology. The surface wall temperature is allowed to vary in the streamwise direction in an arbitrary fashion and calculations are carried out for the turbulent free convection about the horizontal circular cylinder and the sphere for the sake of illustration.

scholarly journals Free Convection Heat Transfer from Horizontal Cylinders

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 559
Author(s):  
Janusz T. Cieśliński ◽  
Slawomir Smolen ◽  
Dorota Sawicka
Keyword(s):  
Heat Transfer ◽  
Rayleigh Number ◽  
Free Convection ◽  
Convection Heat Transfer ◽  
Horizontal Tube ◽  
Correlation Equations ◽  
Convection Heat ◽  
Number Range ◽  
Heated Cylinder ◽  
Free Convection Heat

The results of experimental investigation of free convection heat transfer in a rectangular container are presented. The ability of the commonly accepted correlation equations to reproduce present experimental data was tested as well. It was assumed that the examined geometry fulfils the requirement of no-interaction between heated cylinder and bounded surfaces. In order to check this assumption recently published correlation equations that jointly describe the dependence of the average Nusselt number on Rayleigh number and confinement ratios were examined. As a heat source served electrically heated horizontal tube immersed in an ambient fluid. Experiments were performed with pure ethylene glycol (EG), distilled water (W), and a mixture of EG and water at 50%/50% by volume. A set of empirical correlation equations for the prediction of Nu numbers for Rayleigh number range 3.6 × 104 < Ra < 9.2 × 105 or 3.6 × 105 < Raq < 14.8 × 106 and Pr number range 4.5 ≤ Pr ≤ 160 has been developed. The proposed correlation equations are based on two characteristic lengths, i.e., cylinder diameter and boundary layer length.

Sign in / Sign up

Export Citation Format

Share Document