Friction Loss and Heat Transfer of Fibre and Wood Pulp Suspensions: A Review

2018 ◽  
Author(s):  
Shirin Ghatrehsamani ◽  
Yiannis Ampatzidis ◽  
Sahar Ghatrehsamani
Keyword(s):  
Heat Transfer ◽  
Wood Pulp ◽  
Friction Loss ◽  
Pulp Suspensions

Characterization of heat transfer and friction loss of water turbulent flow in a narrow rectangular duct under 25–40 kHz ultrasonic waves

Ultrasonics ◽  
2021 ◽  
Vol 114 ◽  
pp. 106366
Author(s):  
Korpong Viriyananon ◽  
Jirachai Mingbunjerdsuk ◽  
Teerapat Thungthong ◽  
Weerachai Chaiworapuek
Keyword(s):  
Heat Transfer ◽  
Turbulent Flow ◽  
Ultrasonic Waves ◽  
Friction Loss ◽  
Rectangular Duct

scholarly journals Experimental Study of Heat Transfer Enhancement and Friction Loss Induced by Inserted Rotor-assembled Strand (I) Water

2008 ◽  
Vol 16 (6) ◽  
pp. 849-855 ◽  
Author(s):  
Pengcheng XIE ◽  
Fengxiang LI ◽  
Yumei DING ◽  
Hua YAN ◽  
Changfeng GUAN ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Heat Transfer Enhancement ◽  
Friction Loss ◽  
Transfer Enhancement

Heat Transfer Enhancement of Impingement Cooling by Different Crossflow Diverters

2021 ◽  
Author(s):  
Juan He ◽  
Qinghua Deng ◽  
Kun Xiao ◽  
Zhenping Feng
Keyword(s):  
Heat Transfer ◽  
Velocity Ratio ◽  
Three Dimensional ◽  
Local Heat ◽  
Friction Loss ◽  
Navier Stokes ◽  
Impingement Cooling ◽  
Streamwise Location ◽  
Overall Evaluation ◽  
The Cost

Abstract Impingement cooling can effectively disperse local heat load, but its downstream heat transfer is always reduced due to crossflow effect. In this study, the flow and heat transfer characteristics of impingement cooling with Semi-Circular (SC), Semi-Rectangular (SR), Semi-Diamond (SD) and Semi-Four-pointed Star (SFS) crossflow diverters are compared over the ReD ranging from 3,500 to 14,000 by solving three dimensional Reynolds-Averaged Navier-Stokes (RANS) equations with SST k-? turbulence model. It is found that crossflow diverters change the distribution of local jet Reynolds number (ReD,j/ReD) and reduce the mass velocity ratio of downstream crossflow to jet (Gcf/Gj), so they enhance the heat transfer significantly, but also come at the cost of friction loss. Overall evaluation reveals that various crossflow diverters can improve the comprehensive heat transfer performance parameter (F), and the maximum increases are 11.0%, 14.3%, 12.2% and 14.7% for SC, SR, SD and SFS cases respectively. It is noted that the Nusselt number of heated SFS-shaped diverter surface is also the highest. Besides, the influences of streamwise location (L) and thickness (t) of SFS-shaped diverter are also investigated. Results show that the heat transfer and friction loss change a little when the L increases from 2D to 3D, but the heat transfer decreases sharply and friction loss increases seriously when the L increases from 3D to 4D. With respect to the t, it has almost no effect on the flow field and heat transfer.

Experimental Investigation to Evaluate the Optimum Performance of Helical Coiled Tube with Insert and Nano-Fluid

2014 ◽  
Vol 1036 ◽  
pp. 89-94
Author(s):  
Saleh Mahdi Qasim ◽  
Sahar A. Fattah ◽  
Osama M. Jassim
Keyword(s):  
Heat Transfer ◽  
Experimental Investigation ◽  
Nusselt Number ◽  
Swirl Flow ◽  
Friction Loss ◽  
Test Fluid ◽  
Dean Number ◽  
Coiled Tube ◽  
Helical Tube ◽  
Wire Coil

In the present work an experimental investigation is carried out to evaluate the performance of helical coiled tube with the swirl flow device using Al2O3nanofluid.The effects of wire coil insert with different parameter on heat transfer and friction loss in the helical tube were examined with Dean number (De) ranging from 700 to 2000. The circular or square coil wire has different cross sections, insertedin the tube with different pitch. The wire coil with Al2O3 nanoparticles with a diameter of 80nm dispersed in distilled water with volume concentrations of (0.08,0.1, 0.2and 0.3 vol.% ) were used as the test fluid. The effects of Dean Number, volume concentration of suspended nanoparticles, and wire coil on heat characteristics were investigated. The results reveal that the use of tabulators leads to a considerable increase in heat transfer and friction loss over those of a smooth tube. The Nusselt number increases with increasing of Dean number and reduction in pitch of wire coil. The square type of wire coil provides slightly higher heat transfer than the circular under the same conditions. Results show that the optimum heat transfer is caused of P=15mm of wire coils. Adding nanoparticles to the base fluid causes a significant enhancement in heat transfer characteristics. The overall enhancement in heat transfer using two mechanisms simultaneously compared to using pure fluid within the smooth helical tube exceeds over 213.2% (180% spring enhancement +33.2%Al2O3). The optimum results were found to be P=15mm, φ=0. 3Al2O3 t=2mm square cross section and De=1889. Finally, empirical correlations are developed of predicting Nusselt number of the flow with and without nanofluid. Comparison between the present result in reference results show good agreement.

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