Abstract
The heat transfer enhancement and pressure drop of non-Newtonian power-law fluid flow due to the presence of a bluff body inside a channel are numerically investigated. Different cross-section geometries such as circular, elliptical, trapezoidal, and inclined square cylinders with the angles of 0°, 15°, 30°, and 45° are studied and compared with straight channel. The results are presented as streamlines, local and average Nusselt number, friction factor and thermo-hydraulic performance for the Reynolds number of 10, 20, and 30, Prandtl number of 100, and power-law index of 0.4, 0.6, 0.8, and 1. The blockage ratio is considered as 0.25 for all the cases. The results show that the thermo-hydraulic performance increases by decreasing the power-law index and the square cylinder with inclined angle of 45° has maximum thermo-hydraulic performance. The effect of the cylinder geometry on the heat transfer enhancement was more than that of the power-law index.
Similar content being viewed by others
Abbreviations
- \(c_{p}\) :
-
Specific heat of the fluid (\({\text{J kg}}^{ - 1} {\text{K}}^{ - 1}\))
- \(D\) :
-
Characteristic length (diameter or side of cylinder) (m)
- \(H\) :
-
Height of the channel (m)
- \(h\) :
-
Convective heat transfer coefficient (\({\text{Wm}}^{ - 2} {\text{K}}^{ - 1}\))
- \({\mathbf{I}}_{2}\) :
-
Second invariant of the rate of deformation tensor (\({\text{s}}^{ - 2}\))
- \(k\) :
-
Thermal conductivity of fluid (W/m K)
- \(L\) :
-
Channel length (m)
- \(m\) :
-
Power-law consistency index (Pa.sn)
- \(Nu\) :
-
Local Nusselt number
- \(Nu_{\text{avg}}\) :
-
Average Nusselt number
- \(n\) :
-
Power-law flow behavior index
- \(p\) :
-
Pressure (\({\text{Pa}}\))
- \(Pr\) :
-
Prandtl number
- \(Re\) :
-
Reynolds number
- \(T\) :
-
Temperature (K)
- \(T_{\text{b}}\) :
-
Bulk temperature (K)
- \(T_{\infty }\) :
-
Temperature of fluid at the inlet (K)
- \(T_{\text{w}}\) :
-
Constant wall temperature (K)
- \(U_{x} , U_{y}\) :
-
x- and y-components of velocity (\({\text{m s}}^{ - 1}\))
- \(U_{\infty }\) :
-
Velocity at the channel inlet (m s-1)
- \(x, y\) :
-
Streamwise and transverse coordinates (m)
- \(x_{\text{d}}\) :
-
Downstream length (m)
- \(x_{\text{u}}\) :
-
Upstream length (m)
- \(\alpha\) :
-
Angle of incidence, degree
- \(\beta\) :
-
Blockage ratio (\(D/H\))
- \(\theta\) :
-
Dimensionless temperature
- \({\varvec{\upvarepsilon}}\) :
-
Component of the rate of the strain tensor (\({\text{s}}^{ - 1}\))
- \(\eta\) :
-
Viscosity (\({\text{Pa}}\;{\text{s}}\))
- \(\rho\) :
-
Density of the fluid (\({\text{kg/m}}^{3}\))
- \({\varvec{\uptau}}\) :
-
Extra stress tensor (\({\text{Pa}}\))
- \(\delta\) :
-
Smallest grid size (m)
- avg:
-
Average
- ∞:
-
Inlet condition
- w:
-
Wall
References
Bergles AE (1998) Techniques to enhance heat transfer. In: Rohsenow WM, Hartnett JP, Cho YI (eds) Handbook of heat transfer, 3rd edn. McGraw-Hill, New York (chapter 11)
Léal L, Miscevic M, Lavieille P, Amokrane M, Pigache F, Topin F, Nogarède B, Tadrist L (2013) An overview of heat transfer enhancement methods and new perspectives: focus on active methods using electroactive materials. Int J Heat Mass Transf 61:505–524
Wright LM, Han JC (2013) Heat transfer enhancement for turbine blade internal cooling. In: Proceedings of the ASME 2013 heat transfer summer conference, Minneapolis, MN, July 2013, Paper No. HT2013-17813
Turki S, Abbassi H, Nasrallah SB (2003) Two-dimensional laminar fluid flow andheat transfer in a channel with a built-in heated square cylinder. Int J Therm Sci 42:1105–1113
Kumar A, Dhiman A (2015) Laminar flow and heat transfer phenomena across a confined semi-circular bluff body at low Reynolds numbers. Heat Transf Eng 36:1540–1551
Dhiman A, Verma S, Ghosh R (2015) Laminar momentum and heat transfer in a channel with a built-in tapered trapezoidal bluff body, heat transfer. Heat Transf Asian Res 44:324–346
Mettu S, Verma N, Chhabra RP (2006) Momentum and heat transfer from an asymmetrically confined circular cylinder in a plane channel. Heat Mass Transf 42:1037–1048
Srikanth S, Dhiman AK, Bijjam S (2010) Confined flow and heat transfer across a triangular cylinder in a channel. Int J Therm Sci 49:2191–2200
Huang Z, Xi G, Zhang W, Wen S (2013) Mixed convection heat transfer from confined tandem square cylinders in a horizontal channel. Int J Heat Mass Transf 66:625–631
Agarwal R, Dhiman A (2014) Flow and heat transfer phenomena across two confined tandem heated triangular bluff bodies. Numer Heat Transf Part A Appl 66:1020–1047
Chhabra RP, Richardson JF (2008) Non-Newtonian flow and applied rheology. Butterworth-Heinemann, Oxford
Kumar A, Dhiman AK, Bharti RP (2014) Power-law flow and heat transfer over an inclined square bluff body: effect of blockage ratio. Heat Transf Asian Res 43:167–196
Aboueian-Jahromi J, Hossein Nezhad A, Behzadmehr A (2011) Effects of inclination angle on the steady flow and heat transfer of power-law fluids around a heated inclined square cylinder in a plane channel. J Nonnewton Fluid Mech 166:1406–1414
Kumar A, Dhiman A, Baranyi L (2015) CFD analysis of power-law fluid flow and heat transfer around a confined semi-circular cylinder. Int J Heat Mass Transf 82:159–169
Bijjam S, Dhiman A, Gautam V (2015) Laminar momentum and heat transfer phenomena of power-law dilatant fluids around an asymmetrically confined cylinder. Int J Therm Sci 88:110–127
Agarwal R, Dhiman A (2015) Confined flow and heat transfer phenomena of non-Newtonian shear-thinning fluids across a pair of tandem triangular bluff bodies. Numer Heat Transf Part A Appl 68:174–204
Yoon DH, Yang KS, Choi CB (2009) Heat transfer enhancement in channel flow using an inclined square cylinder. J Heat Transf 131:074503–074504
Moussaoui MA, Jami M, Mezrhab A, Naji H (2010) MRT-lattice Boltzmann simulation of forced convection in a plane channel with an inclined square cylinder. Int J Therm Sci 49:131–142
Seyyedi SM, Bararnia H, Ganji DD, Gorji-Bandpy M, Soleimani S (2012) Numerical investigation of the effect of a splitter plate on forced convection in a two dimensional channel with an inclined square cylinder. Int J Therm Sci 61:1–14
Seyyedi S, Ganji D, Gorji M, Bararnia H, Soleimani S (2013) Forced convection heat transfer due to different inclination angles of splitter behind square cylinder. Appl Math Mech 34:541–558
Cheraghi M, Raisee M, Moghaddami M (2014) Effect of cylinder proximity to the wall on channel flow heat transfer enhancement. Comptes Rendus Mécanique 342:63–72
Rao PK, Sasmal C, Sahu AK, Chhabra R, Eswaran V (2011) Effect of power-law fluid behavior on momentum and heat transfer characteristics of an inclined square cylinder in steady flow regime. Int J Heat Mass Transf 54:2854–2867
Sharma SK, Kalamkar VR (2015) Thermo-hydraulic performance analysis of solar air heaters having artificial roughness—a review. Renew Sustain Energy Rev 41:413–435
Li P, Zhang D, Xie Y, Xie G (2016) Flow structure and heat transfer of non-Newtonian fluids in microchannel heat sinks with dimples and protrusions. Appl Therm Eng 94:50–58
Yadav AS, Bhagoria JL (2014) A CFD based thermo-hydraulic performance analysis of an artificially roughened solar air heater having equilateral triangular sectioned rib roughness on the absorber plate. Int J Heat Mass Transf 70:1016–1039
Author information
Authors and Affiliations
Corresponding author
Additional information
Technical Editor: Cezar Negrao.
Rights and permissions
About this article
Cite this article
Sadeghi, H., Izadpanah, E., Babaie Rabiee, M. et al. Effect of cylinder geometry on the heat transfer enhancement of power-law fluid flow inside a channel. J Braz. Soc. Mech. Sci. Eng. 39, 1695–1707 (2017). https://doi.org/10.1007/s40430-016-0695-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s40430-016-0695-3