2015 1(16)

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Terekhov V.I., Bogatko T.V.

Institute of Thermophysics SB RAS, Novosibirsk, Russia


Terekhov, V.I. and Bogatko, T.V., (2015) Heat transfer in an axisymmetric diffuser with sudden expansion, Modern Science: Researches, Ideas, Results, Technologies, Iss. #1(16), PP. 95 - 100.


separated flow; turbulent heat transfer; diffuser; pressure gradient


Results of a numerical study of the influence of a positive pressure gradient in an axisymmetric diffuser with sudden expansion of a circular tube on aerodynamics and turbulent heat transfer in regions of flow separation, reattachment, and relaxation are reported. The air flow prior to separation is assumed to be fully turbulent and to have a constant Reynolds number ReD1 =2 .75·104. The tube expansion degree is ER = (D2/D1)2 = 1.78, and the apex half-angle of the diffuser is varied from 0 to 5. It is found that an increase in the pressure gradient leads to a decrease in the heat transfer intensity in the separation region, and the maximum heat release point moves away from the flow separation point. The calculated results are compared with experimental data. It is shown that the behavior of the separated flow behind the step becomes significantly different as the streamwise pressure gradient changes.


  1. Terekhov V.I., Yarygina N.I., Zhdanov R.F. Heat transfer in turbulent separated flows in the presence of high free-stream turbulence// Intern.J. Heat Mass Transfer. 2003. V. 46. P. 4535-4551.

  2. Терехов В.И., Ярыгина Н.И. Вихреобразование и теплообмен в отрывных потоках за различными преградами // Тепловые процессы в технике. 2009. Т.1. №4. с.122-130.

  3. Kuehn D.M. Effects of adverse pressure gradient on the incompressible reattaching flow over a rearward-facing step// AIAA Journal, Vol. 18, No. 3, March 1980, pp. 343-344.

  4. Driver D.M., Seegmiller H.L. Features of a reattaching turbulent shear layer in divergent channel flow// AIAA J. 1985. v. 23, N. 2. P. 163-171.

  5. Ra S.H., Chang P.K. Effects of pressure gradient on reattaching flow downstream of a reward-facing step// J. Aircraft. 1990. v. 27, N 1. P. 93-95.

  6. Shah M.K., Tachie M.F. Flow relaxation past a transverse square rib in pressure gradients// AIAA J. 2008. v. 46, N 7. P. 1849-1863.

  7. Biswas G., Breuer M., Durst F. Backward-facing step flows for various expansion ratios at low and moderate Reynolds numbers // J. Fluid Eng-ng. 2004. V. 126. P. 362-374.

  8. Menter F.R. Two-equation eddy-viscocity turbulence models for engineering applications / F.R. Menter // AIAA Journal. - 1994. - V.32, N 8. - P. 1598-1605.

  9. Быстров Ю.А. Численное моделирование вихревой интенсификации теплообмена в пакетах труб / Ю.А. Быстров, С.А. Исаев, Н.А. Кудрявцев, А.И. Леонтьев. - Санкт-Петербург: Судостроение, 2005. - 389 с.

  10. Kays W.M., Convective Heat and Mass Transfer (McGraw-Hill, New York, 1966).



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