Heat transfer experiments and correlations for low-Reynolds-number flows of water in vertical annuli

Journal Article · Sun Jan 01 00:00:00 EST 1989 · Heat Transfer Eng.; (United States)

DOI:https://doi.org/10.1080/01457638908939698· OSTI ID:6084287

El-Genk, M S; Rao, D V

This paper presents heat transfer data and correlations for hydrodynamically developed but thermally developing buoyancy-assisted and -opposed flows of water in vertical annuli at low Reynolds numbers (Re < 10/sup 4/). Data are for forced and mixed laminar flows, forced transitional and turbulent flows, and natural laminar and turbulent flows. A general correlation of the forced upflow data (Re < 10/sup 4/) is obtained by superimposing the correlations developed for forced laminar and transitional flows: Nu/sub F/ = (Nu/sub F,L//sup 9/ + Nu/sub F,Tr//sup 9/)/sup 1/9/. Similarly, the data for both the laminar and the mixed laminar flows as well as those for natural laminar flow are correlated by superimposing the correlations developed for forced laminar and natural laminar flows: Nu/sub L/ = (Nu/sub F,L//sup 3/ + Nu/sub N,L//sup 3/)/sup 1/3/. This correlation is in good agreement with the laminar and mixed downflow data, but with a negative sign for Nu/sub N,L/. Although Nu values for natural laminar flow increased proportionally to Ra/sub q//sup 0.2/ and those for natural turbulent flow increased proportionally to Ra/sub q//sup 0.285/, all the natural flow data are correlated by superimposing the correlations developed for natural laminar and natural turbulent flows as Nu/sub N/ = (Nu/sub N,Tu//sup 3/)/sup 1/3/.

• Research Organization: The Univ. of New Mexico, Albuquerque, NM (US)
• OSTI ID: 6084287
• Journal Information: Heat Transfer Eng.; (United States), Vol. 10:2
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
HEAT TRANSFER
CALCULATION METHODS
LAMINAR FLOW
HYDRODYNAMICS
TURBULENT FLOW
CORRELATIONS
DATA ANALYSIS
EXPERIMENTAL DATA
FLUID FLOW
REYNOLDS NUMBER
WATER
DATA
ENERGY TRANSFER
FLUID MECHANICS
HYDROGEN COMPOUNDS
INFORMATION
MECHANICS
NUMERICAL DATA
OXYGEN COMPOUNDS
420400* - Engineering- Heat Transfer &amp; Fluid Flow