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Pulsatile entrance flow in curved pipes: effect of various parameters

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Abstract

This paper presents the results of an experimental study on the developing pulsatile flow in curved pipes with a long, straight pipe upstream. In order to examine the dependence of flow-field development on the governing parameters, LDV measurements were conducted systematically for six cases of flow, where the Womersley number α was varied from 5.5 to 18, the mean Dean number D m was 200 and 300, the flow rate ratio η was 0.5 and 1, and the curvature radius ratio Rc was 10 and 30. Peculiar flow phenomena, such as flow reversal for all values of α and a depression in the axial velocity profile for α = 10, were analyzed by decomposing the axial velocity into a time-mean and a varying component, as well as by obtaining the bias of their profiles. The velocity distributions abruptly change with the phase at turn angles Ω of 15–30°, corresponding to the nondimensional axial length z′ ≅ 1–2 from the bend entrance, and their development along the pipe axis is the most complicated for the flow at a moderate α of 10 and large η of 1. The entrance length in the case of pulsatile flow is shorter than that for steady flow with the same flow rate as the maximum pulsatile flow rate.

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Abbreviations

a :

radius of pipe, a = d/2

C p :

pressure coefficient, C p  = (P − P ref)/(ρW 2 m /2)

D :

Dean number, D = Re Rc −1/2

P :

static pressure at pipe wall

P ref :

reference value of P, i.e., P at z/d = −2

R :

curvature radius of pipe

R c :

curvature radius ratio, R c  = R/a

Re :

Reynolds number, Re = W m d/ν

u, w :

velocities in x and z directions, respectively

W :

axial velocity averaged over cross section

x, y, z :

coordinate system, see Fig. 2

z′:

nondimensional axial length, z′ = z/(aR)1/2

α :

Womersley number, α = a(ω/ν)1/2

β :

deflection of axial flow, see Eqs. (3) and (4)

ϕ :

phase difference, see Eq. (2)

η :

flow rate ratio, η = W o /W m

Θ :

phase angle, Θ = ωt (t: time, ω: angular frequency)

ν :

kinematic viscosity of fluid

ρ :

density of fluid

Ω :

turn angle, see Fig. 2

m, o :

time-mean and amplitude values, respectively

References

  • Austin LR, Seader JD (1974) Entry region for steady viscous flow in coiled circular pipes. AIChE J 20(4):820–822

    Article  Google Scholar 

  • Berger SA, Talbot L, Yao L-S (1983) Flow in curved pipes. Ann Rev Fluid Mech 15:461–512

    Article  Google Scholar 

  • Bovendeerd PHM, Steenhoven AA, Vosse FN, Vossers G (1987) Steady entry flow in a curved pipe. J Fluid Mech 177:233–246

    Article  Google Scholar 

  • Chandran KB, Yearwood TL (1981) Experimental study of physiological pulsatile flow in a curved tube. J Fluid Mech 111:59–85

    Article  Google Scholar 

  • Dwyer HA, Cheer A-Y, Rutaganira T, Shacheraghi N (2001) Calculations of unsteady flows in curved pipes. ASME J Fluids Eng 123:869–877

    Article  Google Scholar 

  • Hamakiotes CC, Berger SA (1988) Fully developed pulsatile flow in a curved pipe. J Fluid Mech 195:23–55

    Article  Google Scholar 

  • Naruse T, Nishina Y, Ishihara K, Tanishita K (1991) Developing pulsatory flow in the internal carotid artery (in Japanese). Trans Jpn Soc Mech Eng B 57(541):3018–3025

    Google Scholar 

  • Pedley TJ (1980) The fluid mechanics of large blood vessels. Cambridge University Press, Cambridge

  • Rindt CCM, Steenhoven AA, Janssen JD, Vossers G (1991) Unsteady entrance flow in a 90° curved tube. J Fluid Mech 226:445–474

    Article  Google Scholar 

  • Simon HA, Chang MH, Chow JCF (1977) Heat transfer in curved tubes with pulsatile, fully developed, laminar flows. ASME J Heat Transf 99:590–595

    Google Scholar 

  • Smith FT (1975) Pulsatile flow in curved pipes. J Fluid Mech 71(1):15–42

    Article  MATH  Google Scholar 

  • Sudo K, Sumida M, Yamane R (1992) Secondary motion of fully-developed oscillatory flow in a curved pipe. J Fluid Mech 237:189–208

    Article  Google Scholar 

  • Sumida M, Sudo K, Takami T (1984) Pulsating flow in curved pipes: 2nd report. Bull JSME 27(234):2714–2721

    Google Scholar 

  • Sumida M, Sudo K (1986) Pulsating flow in curved pipes: 3rd report. Bull JSME 29(256):3334–3340

    Google Scholar 

  • Sumida M, Sudo K, Wada H (1989) Pulsating flow in a curved pipe: secondary flow. JSME Int J Ser II 32(4):523–531

    Google Scholar 

  • Swanson CJ, Stalp SR, Donnelly RJ (1993) Experimental investigation of periodic flow in curved pipes. J Fluid Mech 256:69–83

    Article  Google Scholar 

  • Talbot L, Gong KO (1983) Pulsatile entrance flow in a curved pipe. J Fluid Mech 127:1–25

    Article  Google Scholar 

  • Thiriet M, Graham JMR, Issa RI (1992) A pulsatile developing flow in a bend. J Phys III 2:995–1013

    Article  Google Scholar 

  • Uchida S (1956) The pulsating viscous flow superposed on the steady laminar motion of incompressible fluid in a circular pipe. Z Angew Math Phys 7:403–422

    Article  MATH  MathSciNet  Google Scholar 

  • Yao L-S, Berger SA (1975) Entry flow in a curved pipe. J Fluid Mech 67:177–196

    Article  MATH  Google Scholar 

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Acknowledgment

The author would like to thank Professor Emeritus K. Sudo of Hiroshima University for his useful and helpful suggestions.

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Correspondence to Masaru Sumida.

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Sumida, M. Pulsatile entrance flow in curved pipes: effect of various parameters. Exp Fluids 43, 949–958 (2007). https://doi.org/10.1007/s00348-007-0365-4

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