Magnetorheological Flow in Pipes: An Exploration of the Time-Variation of Herschel-Bulkley Parameters

Volume 8: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A and B ◽

10.1115/imece2007-43915 ◽

2007 ◽

Author(s):

Mario F. Letelier ◽

Juan S. Stockle ◽

Dennis A. Siginer

Keyword(s):

Magnetic Field ◽

Velocity Field ◽

Unsteady Flow ◽

Yield Stress ◽

Magnetic Fluid ◽

Time Variation ◽

Power Index ◽

Time Structure ◽

Time Dependent ◽

Constitutive Parameters

In this paper it is analyzed the effects on the flow of the time-variation of Herschel-Bulkley model of fluid constitutive parameters. In this way, the influence of a varying magnetic field on the unsteady flow of a magnetic fluid is explored. Yield stress, viscosity and power index are assumed time-dependent. In particular, linear variations in time of these parameters are considered. The characteristics of the velocity field is analyzed for different values of the constants that determine the time structure of the constitutive parameters.

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1102 Dependence of Time Variation in Thermal Diffusivity of Magnetic Fluid on Magnetic Field Intensity

The Proceedings of the Fluids engineering conference ◽

10.1299/jsmefed.2015._1102-1_ ◽

2015 ◽

Vol 2015 (0) ◽

pp. _1102-1_-_1102-2_

Author(s):

Takashi MURAOKA ◽

Masaaki MOTOZAWA ◽

Masahiro MOTOSUKE ◽

Mitsuhiro FUKUTA

Keyword(s):

Magnetic Field ◽

Thermal Diffusivity ◽

Field Intensity ◽

Magnetic Fluid ◽

Time Variation ◽

Magnetic Field Intensity

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Unsteady flow of a generalized Oldroyd-B fluid due to an infinite plate subject to a time-dependent shear stress

Canadian Journal of Physics ◽

10.1139/p10-055 ◽

2010 ◽

Vol 88 (9) ◽

pp. 675-687 ◽

Cited By ~ 7

Author(s):

D. Vieru ◽

Corina Fetecau ◽

C. Fetecau

Keyword(s):

Shear Stress ◽

Velocity Field ◽

Boundary Conditions ◽

Unsteady Flow ◽

Infinite Plate ◽

Time Dependent ◽

Fourier Cosine ◽

Series Form ◽

Maxwell Fluids ◽

An Inverse Approach to Magnetorheological Damper Design: Hershel-Bulkley Model

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2008-55058 ◽

2008 ◽

Author(s):

Mario F. Letelier ◽

Juan S. Stockle ◽

Dennis A. Siginer

Keyword(s):

Magnetic Field ◽

Yield Stress ◽

A Priori ◽

Variable Magnetic Field ◽

Magnetorheological Damper ◽

Heavy Vehicles ◽

Aircraft Landing ◽

Self Powered ◽

Damper Design ◽

Constitutive Parameters

Magnetorheological fluids (MRF) are increasingly used for the design of dampers in many cases when a given response is critical for desired performance. Some recent examples are self-powered magnetorheological dampers, cable vibration control and wheeled vehicle dampers. Loads of this type can be very big, especially in the case of seismic-dampers as well as in heavy vehicles and aircraft landing gear. This problem can be more efficiently dealt with by using an inverse-problem strategy, where the required performance is specified a priori, and the fluid parameters are changed accordingly by means of a variable magnetic field. The effect on the flow of the time-variation of the parameters of the Herschel-Bulkley constitutive model is analyzed in this paper. In this way, the influence of a varying magnetic field on the unsteady flow of a magnetic fluid is explored. Yield stress, viscosity and power index are assumed time-dependent. In particular, linear variations in time of these parameters are considered, and the case where the yield stress and viscosity oscillate in time is explored in detail. The characteristics of the velocity field are analyzed for different values of the constants that determine the time structure of the constitutive parameters.

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Unsteady MHD Flow Due to Non-Coaxial Rotations of a Porous Disk and a Fluid at Infinity Subjected to a Periodic Suction

International Journal of Applied Mechanics and Engineering ◽

10.2478/ijame-2018-0034 ◽

2018 ◽

Vol 23 (3) ◽

pp. 623-633

Author(s):

M. Guria

Keyword(s):

Magnetic Field ◽

Fixed Point ◽

Velocity Field ◽

Unsteady Flow ◽

Mhd Flow ◽

Transverse Magnetic ◽

Shear Stresses ◽

Porous Disk ◽

Electrically Conducting ◽

Electrically Conducting Fluid

Abstract The unsteady flow of a viscous incompressible electrically conducting fluid due to non-coaxial rotations of a porous disk subjected to a periodic suction and the fluid at infinity in the presence of applied transverse magnetic field has been studied. The fluid at infinity passes through a fixed point. The velocity field, shear stresses are obtained in a closed form.

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AXIAL COUETTE FLOW OF AN ELECTRICALLY CONDUCTING FLUID IN AN ANNULUS

International Journal of Modern Physics B ◽

10.1142/s0217979208039587 ◽

2008 ◽

Vol 22 (15) ◽

pp. 2489-2500 ◽

Cited By ~ 6

Author(s):

T. HAYAT ◽

E. MOMONIAT ◽

F. M. MAHOMED

Keyword(s):

Magnetic Field ◽

Velocity Profile ◽

Unsteady Flow ◽

Couette Flow ◽

Applied Magnetic Field ◽

Nonlinear Effects ◽

Time Dependent ◽

Electrically Conducting ◽

Electrically Conducting Fluid ◽

Numerical Approaches

The unsteady flow in an annulus due to a velocity applied to one of the boundaries is addressed. The fluid considered is non-Newtonian, incompressible and electrically conducting. The strength of the applied magnetic field is time-dependent. Both analytical and numerical approaches are presented and compared. The nonlinear effects on the velocity profile are shown.

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An Inverse Method for Material Characterization of Magnetorheological Dampers

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2007-37305 ◽

2007 ◽

Author(s):

Mario F. Letelier ◽

Dennis A. Siginer ◽

Jean-Paul Rouliez ◽

Omar F. Corral

Keyword(s):

Magnetic Field ◽

Yield Stress ◽

Time History ◽

Field Variation ◽

Mr Fluid ◽

Bingham Plastic ◽

Damper Design ◽

Analytical Tools ◽

Constitutive Parameters

Flow of magnetorheological (MR) fluids in dampers is investigated. The MR fluid flows through narrow passages in the damper subject to a magnetic field applied across the passages. The inverse problem of the determination of the required constitutive properties of the MR fluid together with the corresponding flow pattern for the efficient damping of a given load is solved. The fluid is modeled as a Bingham plastic with time-varying yield-stress. Flow is governed by the continuously adjustable constitutive parameters of the MR fluid which are determined to generate variable resistance to flow to dampen the selected load efficiently. The method developed leads to the determination of the magnetic field variation necessary to achieve a specific displacement of the piston in the damper. The governing equations are solved for any time history of the dimensionless yield stress of the fluid. Relationships that correlate damping load and magnetic field time variations are obtained. The analytical tools developed are helpful in damper design.

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Oscillatory Flow of Magnetorheological Fluids in Pipes

Fluids Engineering ◽

10.1115/imece2006-13088 ◽

2006 ◽

Author(s):

Mario F. Letelier ◽

Dennis A. Siginer

Keyword(s):

Magnetic Field ◽

Pressure Gradient ◽

Flow Velocity ◽

Yield Stress ◽

Oscillatory Flow ◽

Bingham Fluid ◽

Time Dependent ◽

Magnetic Flow ◽

The Magnetic Field ◽

Oscillatory Pressure

In this paper it is analysed the case of an oscillatory flow in a round pipe in which a magnetic flow is applied. In magnetorheological flows (MRF) the fluid develops yield stress, the strength of which depends on the intensity of the magnetic field. The analysis considers an oscillatory pressure gradient and an oscillatory magnetic field of different frequencies. It is investigated the effect of a cyclical yield stress on the frequency and amplitude of the flow velocity, including the phenomenon of resonance. In this study, the MFR is modelled as a Bingham fluid with time- dependent yield stress.

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