On the Nusselt Number for H2 Heat Transfer in Rectangular Ducts of Large Aspect Ratios

2014 ◽  
Vol 136 (7) ◽  
Author(s):  
C. Y. Wang
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Aspect Ratio ◽  
Forced Convection ◽  
Parallel Plate ◽  
Convection Heat Transfer ◽  
Analytic Method ◽  
Convection Heat ◽  
Forced Convection Heat Transfer ◽  
Aspect Ratios

The H1 and H2 forced convection heat transfer in rectangular ducts are studied using an accurate, analytic method. It is confirmed that, as the aspect ratio tends to infinity, the Nusselt number for the H2 case approaches 2.9162, much lower than the parallel plate value of 8.2353 attained by the H1 case. The controversy about the H2 limit is thus settled. An explanation of the behavior is suggested.

AN EXPERIMENTAL STUDY OF ENHANCEMENT OF FORCED CONVECTION HEAT TRANSFER FROM PARALLEL PLATE FINS WITH CUTS

Equipment ◽  
2006 ◽  
Author(s):  
E. N. Pis'mennyi ◽  
V. A. Rogachev ◽  
A. M. Terekh ◽  
Georgiy Polupan ◽  
I. Carvajal-Mariscal ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Forced Convection ◽  
Parallel Plate ◽  
Convection Heat Transfer ◽  
Convection Heat ◽  
Forced Convection Heat Transfer

Simplified Analytical Models for Forced Convection Heat Transfer From Cuboids of Arbitrary Shape

2000 ◽  
Vol 123 (3) ◽  
pp. 182-188 ◽  
Author(s):  
J. R. Culham ◽  
M. M. Yovanovich ◽  
P. Teertstra ◽  
C.-S. Wang ◽  
G. Refai-Ahmed ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Flat Plate ◽  
Forced Convection ◽  
Convection Heat Transfer ◽  
Analytical Models ◽  
Convection Heat ◽  
Forced Convection Heat Transfer ◽  
Aspect Ratios ◽  
Diffusive Limit

Three analytical models are presented for determining laminar, forced convection heat transfer from isothermal cuboids. The models can be used over a range of Reynolds number, including at the diffusive limit where the Reynolds number goes to zero, and for a range of cuboid aspect ratios from a cube to a flat plate. The models provide a simple, convenient method for calculating an average Nusselt number based on cuboid dimensions, thermophysical properties and the approach velocity. Both the cuboid and the equivalent flat plate models are strongly dependent upon the flow path length which is bounded between two easily calculated limits. In comparisons with numerical simulations, the models are shown to be within ±6 percent over the range of 0⩽ReA⩽5000 and aspect ratios between 0 and 1.

scholarly journals Investigation Of Forced Convection Heat Transfer From A Heater Mounted Ina Cavity Wall Using Various Nanofluids

2019 ◽  
Vol 128 ◽  
pp. 07002
Author(s):  
R. Kanna ◽  
Sayed Sayeed Ahmad ◽  
P. Venkata Reddy ◽  
Chithirai Pon Selvan ◽  
Tale ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Nusselt Number ◽  
Forced Convection ◽  
Volume Fraction ◽  
Convection Heat Transfer ◽  
Cavity Wall ◽  
Main Stream ◽  
Convection Heat ◽  
Forced Convection Heat Transfer

Forced convection heat transfer from heater mounted in a cavity wall is investigated to reveal the relation among nanofluid properties. The base fluid is considered as water. The present study is focused on forced convection heat transfer from square heater subject to inflow and outflow inside a squarecavity. The interesting physics will be reported in connection with volume fraction, Reynolds number and nanomaterial properties. It is found that for a particular Reynolds number when nanomaterial is introduced the local heat transfer is increased. The wall attached vortex attributes a constant Nusselt number. It is also noticed that when the heater wall is subject to combination of vortex and main stream fluid results high Nusselt number than heat transfer due to wall attached vortices. Nanofluid results high Nusselt number for the same Reynolds number.

scholarly journals Numerical investigation of laminar forced convection heat transfer in rectangular channels with different block geometries using nano-fluids

2017 ◽  
Vol 21 (5) ◽  
pp. 2129-2138 ◽  
Author(s):  
Saeed Foroutani ◽  
Alireza Rahbari
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Nusselt Number ◽  
Forced Convection ◽  
Average Nusselt Number ◽  
Volume Fraction ◽  
Convection Heat Transfer ◽  
Convection Heat ◽  
Forced Convection Heat Transfer ◽  
Triangular Block

This research investigates the laminar steady-forced convection heat transfer of a Cu-water nanofluid in a 2-D horizontal channel with different block geometries attached to the bottom wall. The block geometries assumed in this research are triangular and curve blocks. The governing equations associated with the required boundary conditions are solved using finite volume method based on the SIMPLE technique and the effects of Reynolds number, nanofluid volume fraction, block geometry, and the numbers of blocks on the local and average Nusselt numbers are explored. The obtained results show that nanoparticles can effectively enhance the heat transfer in a channel. Furthermore, the local and average Nusselt number distribution is strongly dependent on the block geometry. As observed, the heat transfer augments with the increase in the Reynolds number and nanofluid volume fraction for both block geometries. It is also concluded that the average Nusselt number of the curve block is higher than that of the triangular block for different Reynolds numbers which declares the importance of the block geometry in the heat transfer enhancement.

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