Effect of Oscillatory Motion in Enhancing the Natural Convection Heat Transfer from a Vertical Channel
Main Article Content
Abstract
This paper reports an experimental study regarding the influence of vertical oscillations on the natural convection heat transfer from a vertical channel. An experimental set-up was constructed and calibrated; the vertical channel was tested in atmosphere at 25o
C. The channel-to-ambient temperature difference was varied with the power supply to the electrical heater ranging between
15W to 70W divided into five levels. Data sets were measured under different operating condition from a test rig under six vibrating velocities (VVs) levels ranging from (5-30 m/s) in addition to the stationary state. The results show that the maximum heat transfer enhancement factor (E) occurs at Rayleigh number (Ra=2.328×103 ) and vibrational Reynolds number ( Rev=6.365×103 ); this
enhancement reached to (7.685%).The results also illustrated that the temperature gradient along the channel wall length was enhanced by inducing the oscillatory motion to the channel. Rayleigh and vibrational Reynolds numbers were ranging between (2.306×103 - 5.564×103) and (0.0 - 19.86×103) respectively. Finally, A correlation which summarized the effects of both Ra and Rev was
determined for the Nusselt numbers.
Article Details
How to Cite
Publication Dates
References
C.G. Rao, C. Balaji, S.P. Venkateshan," Effect of surface radiation on conjugate mixed convection in a vertical channel with a discrete heat source in each wall", Int. J. Heat Mass Transfer 45 (2002) 3331–3347.
Daloglu A, Ayhan T ,”Natural Convection in a Periodically Finned Vertical Channel”, International Communication Heat Mass Transfer 26 (1999) 1175–1182.
E. Kchoc, M. Davics, D. Newport, "Mixed convection cooling of horizontally mounted printed circuit board", IEEE Trans. Comp. Packag. Technol. 26 (2003) 126–133.
Fu WS, Shieh WJ ,” Transient ThermalConvection in an Enclosure Induced Simultaneously by Gravity and Vibration”, International Journal of Heat and Mass Transfer 36 (1993) 437–452.
Incropera FP ,”Liquid cooling of electronic devices”, Wiley, New York, (1999) 1–14.
Incropera FP, DeWitt DP ,”Introduction to heat transfer”, Wiley, New York (1996).
Khanafer K, Vafai K ,” Buoyancy-driven flow and heat transfer in an open-ended enclosures: elimination of the extended boundaries”,
International Journal of Heat and Mass Transfer 43 (2000) 4087–4100.
Kwak HS; Kuwahara K, Hyun JM,” Resonant Enhancement of Natural Convection Heat Transfer in a Square Enclosure”, International Journal of Heat and Mass Transfer 41 (1998) 2837–2846.
L. A. Florio ,A. Harnoy,” Analysis of dynamic enhancement of natural convection cooling by a discrete vibrating plate”, Heat Mass Transfer (2006) 43: 149–163.
L. Cheng , T. Luan, W. Du, M. Xu,” Heat transfer enhancement by flow-induced vibration in heat exchangers”, International Journal of Heat and Mass Transfer 52 (2009) 1053–1057.
M. Dogan , M. Sivrioglu, "Experimental investigation of mixed convection heat transfer from longitudinal fins in a horizontal rectangular
channel", International Journal of Heat and Mass Transfer 53 (2010) 2149–2158.
N. Bianco,T , S. Nardini ,” Numerical analysis of natural convection in air in a vertical convergent channel with uniformly heated conductive walls”, International Communications in Heat and Mass Transfer 32 (2005) 758–769.
N. Kasayapanand , T. Kiatsiriroat ,” Numerical modeling of the electrohydrodynamic effect to natural convection in vertical
channels”,International Communications in Heat and Mass Transfer 34 (2007) 162–175.
Oronzio Manca , Marilena Musto , Vincenzo Naso ,” Experimental analysis of asymmetrical isoflux channel-chimney systems”, International Journal of Thermal Sciences 42 (2003) 837–846.
P. Poskas , R. Poskas, A. Sirvydas, A. Smaizys,” Experimental investigation of opposing mixed convection hear transfer in the vertical flat channel in a laminar–turbulent transition region”, International Journal of Heat and Mass Transfer 54 (2011) 662–668.
Ramanathan S, Kumar R ,”Correlations for Natural Convection between Heated Vertical Plates”, Journal of Heat Transfer 113(1991) 97–
Sathe S ,”A review of recent developments in some practical aspects of air-cooled electronic packages”, J. Heat Transfer 120 (1998) 830–838.
Subhrajit Dey ,Debapriya Chakrborty,”Enhancement of convective cooling using oscillating fins”, International Journal of Heat and Mass Transfer 36 (2009) 508–512.
Tou SKW, Tso CP, Zhang X ,”3-D numerical analysis of natural convective liquid cooling of a 3×3 heater array in rectangular enclosures”, Int. J. Heat Mass Transfer 42 (1999) 3231–3244.
Vafai K, Ettefagh J ,”The Effects of Sharp Corners on Buoyancy-Driven Flows with Particular Emphasis on Outer Boundaries”, International Journal of Heat and Mass Transfer 33(1990a) 2311–2328.
Vafai K, Ettefagh J,” Thermal and Fluid Flow Instabilities in Buoyancy-Driven Flows in OpenEnded Cavities”, International Journal of Heat and Mass Transfer 33(1990b) 2329–2344.
Wu-Shung Fu , Chien-Ping Huang,” Effects of a vibrational heat surface on natural convection in a vertical channel flow”, International Journal of Heat and Mass Transfer 49 (2006) 1340–1349.
X.R. Zhang , S. Maruyama, S. Sakai,” Numerical investigation of laminar natural convection on a heated vertical plate subjected to a periodic oscillation”, International Journal of Heat and Mass Transfer 47 (2004) 4439–4448.Yeh LT ,”Review of heat transfer technologies in electronic equipment”, J. Electron Package Trans ASME 117 (1995) 333–337.