Surface-tension effects in oscillatory squeeze flow rheometry

A numerical algorithm for fully dynamical lubrication problems based on the Elrod–Adams formulation of the Reynolds equation with mass-conserving boundary conditions is described. A simple but effective relaxation scheme is used to update the solution maintaining the complementarity conditions on the variables that represent the pressure and fluid fraction. The equations of motion are discretized in time using Newmark’s scheme, and the dynamical variables are updated within the same relaxation process just mentioned. The good behavior of the proposed algorithm is illustrated in two examples: an oscillatory squeeze flow (for which the exact solution is available) and a dynamically loaded journal bearing. This article is accompanied by the ready-to-compile source code with the implementation of the proposed algorithm.

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Oscillatory squeeze flow of suspensions of magnetic polymerized chains

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/20/20/204132 ◽

2008 ◽

Vol 20 (20) ◽

pp. 204132 ◽

Cited By ~ 2

Author(s):

P Kuzhir ◽

M T López-López ◽

G Vertelov ◽

Ch Pradille ◽

G Bossis

Keyword(s):

Squeeze Flow ◽

Oscillatory Squeeze Flow

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Electrorheological Fluids in Squeeze under AC and DC Excitation

International Journal of Modern Physics B ◽

10.1142/s0217979299001892 ◽

1999 ◽

Vol 13 (14n16) ◽

pp. 1861-1869 ◽

Cited By ~ 6

Author(s):

J. L. Sproston ◽

A. K. El Wahed ◽

R. Stanway

Keyword(s):

Excitation Frequency ◽

Rheological Behaviour ◽

Electrorheological Fluids ◽

Squeeze Flow ◽

Dc Excitation ◽

Rate Characteristic ◽

Input Waveform ◽

Comparison Of The Results ◽

Er Fluid ◽

Oscillatory Squeeze Flow

This paper is concerned with an experimental investigation of the performance of an ER fluid in oscillatory squeeze-flow and a comparison of the results with those predicted by a quasi-steady theoretical model in which the rheological behaviour of the fluid is assumed to follow a bi-viscous shears stress/shear rate characteristic. The fluid is sandwiched between two parallel plane electrodes, the upper one stationary and the lower one oscillating normal to its plane. Of particular interest is the temporal variation in the force transmitted through the fluid in response to changes in the oscillation frequency and amplitude and the level of applied AC and DC voltages. The magnitude of the transmitted forces in the AC case is seen to be not only a function of the applied voltage but also of the shape of the input waveform and the electrical excitation frequency. In all cases these forces are found to be smaller than those seen in the corresponding DC case.

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