### Abstract

Pulsatile flows of a Bingham plastic through a circular pipe have been investigated numerically. The unsteadiness in the studied flow phenomenon is due to a sinusoidal varying pressure gradient component superimposed on a non-zero mean value. These time periodic flows are typical of many pumping operations and manufacturing processes of highly viscous Newtonian and non-Newtonian fluids. Pulsating the flow of a non-Newtonian Bingham plastic leads to time-averaged flow rates that are higher than the ones obtained under steady state conditions. The influence of the governing non-dimensional parameters, i.e. the yield, Reynolds and Strouhal numbers, on both the flow rate enhancement as well as the extra power required to maintain the flow pulsations is investigated. The presented results identify two asymptotic flow regimes. The first is a quasi-steady state one encountered at low frequencies. The other limiting regime, found at the high end of the studied frequency spectrum, leads to time-averaged characteristics identical to those of the steady state case.

Original language | English (US) |
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Title of host publication | American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED |

Pages | 685-690 |

Number of pages | 6 |

Volume | 237 |

State | Published - 1996 |

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### ASJC Scopus subject areas

- Engineering(all)

### Cite this

*American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED*(Vol. 237, pp. 685-690)

**Pulsatile flows of a bingham plastic in circular pipes.** / Hammad, Khaled J.; Vradis, George.

Research output: Chapter in Book/Report/Conference proceeding › Chapter

*American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED.*vol. 237, pp. 685-690.

}

TY - CHAP

T1 - Pulsatile flows of a bingham plastic in circular pipes

AU - Hammad, Khaled J.

AU - Vradis, George

PY - 1996

Y1 - 1996

N2 - Pulsatile flows of a Bingham plastic through a circular pipe have been investigated numerically. The unsteadiness in the studied flow phenomenon is due to a sinusoidal varying pressure gradient component superimposed on a non-zero mean value. These time periodic flows are typical of many pumping operations and manufacturing processes of highly viscous Newtonian and non-Newtonian fluids. Pulsating the flow of a non-Newtonian Bingham plastic leads to time-averaged flow rates that are higher than the ones obtained under steady state conditions. The influence of the governing non-dimensional parameters, i.e. the yield, Reynolds and Strouhal numbers, on both the flow rate enhancement as well as the extra power required to maintain the flow pulsations is investigated. The presented results identify two asymptotic flow regimes. The first is a quasi-steady state one encountered at low frequencies. The other limiting regime, found at the high end of the studied frequency spectrum, leads to time-averaged characteristics identical to those of the steady state case.

AB - Pulsatile flows of a Bingham plastic through a circular pipe have been investigated numerically. The unsteadiness in the studied flow phenomenon is due to a sinusoidal varying pressure gradient component superimposed on a non-zero mean value. These time periodic flows are typical of many pumping operations and manufacturing processes of highly viscous Newtonian and non-Newtonian fluids. Pulsating the flow of a non-Newtonian Bingham plastic leads to time-averaged flow rates that are higher than the ones obtained under steady state conditions. The influence of the governing non-dimensional parameters, i.e. the yield, Reynolds and Strouhal numbers, on both the flow rate enhancement as well as the extra power required to maintain the flow pulsations is investigated. The presented results identify two asymptotic flow regimes. The first is a quasi-steady state one encountered at low frequencies. The other limiting regime, found at the high end of the studied frequency spectrum, leads to time-averaged characteristics identical to those of the steady state case.

UR - http://www.scopus.com/inward/record.url?scp=0030348748&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030348748&partnerID=8YFLogxK

M3 - Chapter

AN - SCOPUS:0030348748

VL - 237

SP - 685

EP - 690

BT - American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED

ER -