vol18no4pa7

References

  1. Choudhury D. and Patankar S.V. “Combined Forced and Free Laminar Convection in the Entrance Region of an Inclined Isothermal Tube” J Heat Transfer, Vol.110, PP.901-909, November (1988).
  2. Grassi W. and Testi D. “Transitional Mixed Convection in the Entrance Region of a Horizontal Pipe” European Thermal Sciences Conference, the Netherlands, (2008).
  3. Kotake S. and Hattori N” Combined Forced and Free Convection Heat Transfer for Fully Developed Laminar Flow in Horizontal Annuli” Int. J. heat mass transfer. Vol.28, No.11, PP.2113-2120, (1985).
  4. Kaviany, M. “Laminar Combined Convection in a Horizontal Annulus Subject to Constant Heat Flux Inner Wall and Adiabatic Outer Wall” Transactions of the ASME, Vol.108, May (1986).
  5. Hanzawa T., Sako A., Endo H., Kagwa M. and Koto K., “Combined Free and Forced Laminar Convective Heat Transfer From Isothermally Heated Inner Tube in Vertical Concentric Annulus” J. Chemical Engineering of Japan, Vol.19,No.1,PP.78-81,(1986).

Tikrit Journal of Engineering Sciences (2011) 18(4) 60- 70

Heat Transfer by Mixed Convection in the Opposing Thermally Developing Flow in a Vertical and Inclined Annulus

Ameer A. Jadoaa, Electromechanical Eng. Dep.-University of Technology, Iraq

Abstract

Combined convection heat transfer in an inclined (ψ=60o) and vertical (ψ=90o) annulus has been experimentally studied for opposing thermally developing and thermally fully developed laminar air flows with adiabatic inner tube and uniformly heated outer tube (r1/r2=0.41) for Reynolds number range from 450 to 1000 and heat flux is varied from 150 W/m2 to 780 W/m2. The hydrodynamically developed condition has been achieved by using entrance section annular pipe (calming section) having the same dimensions as test section (L/Dh≈40). The mixed convection regime has been bounded by the convenient selection of Re and heat flux ranges, so that the obtained Richardson number varied approximately from 0.05 to 0.97. The average heat transfer results have been correlated with an empirical correlation by dimensionless groups as logNum against logRa/Re and compared with available literature showed that the heat transfer process in the hydrodynamically fully developed region of duct is better than that in the developing region of this duct.

Download Full-text PDF

Keywords: Mixed convection, fully developed, annulus.

 

How to cite

TJES: Jadoaa AA. Heat Transfer by Mixed Convection in the Opposing Thermally Developing Flow in a Vertical and Inclined Annulus. Tikrit Journal of Engineering Sciences 2011; 18(4): 60-70
APA: Jadoaa A. A., (2011). Heat Transfer by Mixed Convection in the Opposing Thermally Developing Flow in a Vertical and Inclined Annulus. Tikrit Journal of Engineering Sciences, 18(4), 60-70.