Electrokinetic energy conversion of fluids with pressure-dependent viscosity in nanofluidic channels

Lamellar membranes with two-dimensional nanofluidic channels hold great promise in harvesting osmotic energy from salinity gradients. However, the power density is often limited by the high transmembrane resistance primarily caused...

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Stochastic Reynolds equation for the combined effects of piezo-viscous dependency and squeeze-film lubrication of micropolar fluids on rough porous circular stepped plates

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/13506501211022452 ◽

2021 ◽

pp. 135065012110224

Author(s):

Hanumagowda Bannihalli Naganagowda ◽

Sreekala Cherkkarathandayan Karappan

Keyword(s):

Carrying Capacity ◽

Stochastic Approach ◽

Squeeze Film ◽

Closed Form Expression ◽

Load Carrying Capacity ◽

Micropolar Fluids ◽

Pressure Dependent Viscosity ◽

Load Carrying ◽

Dependent Viscosity ◽

Film Characteristics

The aim of this paper is to presents a theoretical analysis on squeeze-film characteristics of a rough porous circular stepped plate in the vicinity of pressure-dependent viscosity and lubrication by micropolar fluids. A closed-form expression for non-dimensional pressure, load, and squeezing time is derived based on Eringen’s theory, Darcy’s equation, and Christensen’s stochastic approach. Results indicate that the effects of pressure-dependent viscosity, surface roughness, and micropolar fluids play an important role in increasing the load-carrying capacity and squeezing time, whereas the presence of porous media decreases the load-carrying capacity and squeezing time of the rough porous circular stepped plates.

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Analytical Solutions of Upper Convected Maxwell Fluid with Exponential Dependence of Viscosity under the Influence of Pressure

Mathematics ◽

10.3390/math9040334 ◽

2021 ◽

Vol 9 (4) ◽

pp. 334

Author(s):

Constantin Fetecau ◽

Dumitru Vieru ◽

Tehseen Abbas ◽

Rahmat Ellahi

Keyword(s):

Fluid Motion ◽

Maxwell Fluid ◽

Newtonian Fluids ◽

Exponential Dependence ◽

Physical Parameters ◽

Shear Stresses ◽

Parallel Plates ◽

Pressure Dependent Viscosity ◽

Laplace Transform Technique ◽

Dependent Viscosity

Some unsteady motions of incompressible upper-convected Maxwell (UCM) fluids with exponential dependence of viscosity on the pressure are analytically studied. The fluid motion between two infinite horizontal parallel plates is generated by the lower plate, which applies time-dependent shear stresses to the fluid. Exact expressions, in terms of standard Bessel functions, are established both for the dimensionless velocity fields and the corresponding non-trivial shear stresses using the Laplace transform technique and suitable changes of the unknown function and the spatial variable in the transform domain. They represent the first exact solutions for unsteady motions of non-Newtonian fluids with pressure-dependent viscosity. The similar solutions corresponding to the flow of the same fluids due to an exponential shear stress on the boundary as well as the solutions of ordinary UCM fluids performing the same motions are obtained as limiting cases of present results. Furthermore, known solutions for unsteady motions of the incompressible Newtonian fluids with/without pressure-dependent viscosity induced by oscillatory or constant shear stresses on the boundary are also obtained as limiting cases. Finally, the influence of physical parameters on the fluid motion is graphically illustrated and discussed. It is found that fluids with pressure-dependent viscosity flow are slower when compared to ordinary fluids.

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Pressure-dependent viscosity and free volume of atactic and syndiotactic polystyrene

Rheologica Acta ◽

10.1007/s00397-009-0348-x ◽

2009 ◽

Vol 48 (4) ◽

pp. 467-478 ◽

Cited By ~ 30

Author(s):

Andrea Sorrentino ◽

Roberto Pantani

Keyword(s):

Free Volume ◽

Syndiotactic Polystyrene ◽

Pressure Dependent Viscosity ◽

Dependent Viscosity

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Ion-size effect on electrokinetic energy conversion in nanofluidic channels

International Journal of Green Energy ◽

10.1080/15435075.2016.1206002 ◽

2016 ◽

Vol 13 (10) ◽

pp. 1050-1058 ◽

Cited By ~ 2

Author(s):

Hung-Chun Yeh ◽

Chih-Chang Chang ◽

Ruey-Jen Yang

Keyword(s):

Size Effect ◽

Energy Conversion ◽

Nanofluidic Channels ◽

Ion Size

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Two Dimensional Modified Reynolds Equation Including Pressure Dependent Viscosity Effect

ASME/STLE 2012 International Joint Tribology Conference ◽

10.1115/ijtc2012-61174 ◽

2012 ◽

Author(s):

Jung Gu Lee ◽

Alan Palazzolo

Keyword(s):

Reynolds Equation ◽

Elastohydrodynamic Lubrication ◽

Fluid Film ◽

Maximum Pressure ◽

Elastic Solids ◽

Pressure Distributions ◽

Pressure Dependent Viscosity ◽

Modified Reynolds Equation ◽

Dependent Viscosity ◽

Modified Equation

The Reynolds equation plays an important role for predicting pressure distributions for fluid film bearing analysis, One of the assumptions on the Reynolds equation is that the viscosity is independent of pressure. This assumption is still valid for most fluid film bearing applications, in which the maximum pressure is less than 1 GPa. However, in elastohydrodynamic lubrication (EHL) where the lubricant is subjected to extremely high pressure, this assumption should be reconsidered. The 2D modified Reynolds equation is derived in this study including pressure-dependent viscosity, The solutions of 2D modified Reynolds equation is compared with that of the classical Reynolds equation for the ball bearing case (elastic solids). The pressure distribution obtained from modified equation is slightly higher pressures than the classical Reynolds equations.

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