Numerical simulation of an oil droplet passing through an EHL contact

We present numerical computations of the deformation of an oil-droplet under the influence of a surface tension gradient generated by the surfactant released at the poles (the Greenspan experiment). We find this deformation to be very small under the pure surface tension gradient. To explain the large deformation of oil droplets observed in Greenspan’s experiments, we propose the existence of a phoretic force generated by the concentration gradient of the surfactant. We show that this hypothesis successfully explains the available experimental data and we propose some further tests.

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Numerical Simulation of a Helical Pipe Coalescence Device

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.516-517.1062 ◽

2012 ◽

Vol 516-517 ◽

pp. 1062-1065

Author(s):

Zhen Wang ◽

Ming Hu Jiang ◽

Ping Tao Hou ◽

Qing Jiao Sheng ◽

Li Xin Zhao

Keyword(s):

Numerical Simulation ◽

Structural Parameters ◽

Water Phase ◽

Pipe Diameter ◽

Gyration Radius ◽

Oil Droplet ◽

Inlet Velocity ◽

Helical Pipe ◽

Fluent Software ◽

Operation Parameters

A model of coalescing helical pipe is established through the analysis to the oil phase in continuous water phase inside a helical pipe, by using Fluent software. The influence of structural parameters and operation parameters of helical pipes on oil droplet coalescing effect is verified. Results show that the oil drop coalescing effect increases with the rise of gyration radius and number of turns of helical pipe, and decreases with the rise of the helical pipe diameter and inlet velocity.

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Numerical Simulation of Waviness in A Circular Ehl Contact, Under Rolling/Sliding

Tribology Series - Lubricants and Lubrication - Proceedings of the 21th leeds-Lyon Symposium on Tribology ◽

10.1016/s0167-8922(08)70635-7 ◽

1995 ◽

pp. 259-272 ◽

Cited By ~ 10

Author(s):

C.H. Venner ◽

A.A. Lubrecht

Keyword(s):

Numerical Simulation ◽

Ehl Contact

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Behaviors of a micro oil droplet in an EHL contact

Friction ◽

10.1007/s40544-016-0132-8 ◽

2016 ◽

Vol 4 (4) ◽

pp. 359-368 ◽

Cited By ~ 6

Author(s):

Xinming Li ◽

Feng Guo ◽

Shaopeng Wang ◽

Chenglong Liu ◽

Wenzhong Wang

Keyword(s):

Oil Droplet ◽

Ehl Contact

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Numerical Simulation of a Transverse Ridge in a Circular EHL Contact Under Rolling/Sliding

Journal of Tribology ◽

10.1115/1.2927329 ◽

1994 ◽

Vol 116 (4) ◽

pp. 751-761 ◽

Cited By ~ 106

Author(s):

C. H. Venner ◽

A. A. Lubrecht

Keyword(s):

Numerical Simulation ◽

Film Thickness ◽

Thermal Behavior ◽

Pressure Distribution ◽

Central Axis ◽

Transverse Ridge ◽

Thickness Profile ◽

Smooth Contact ◽

Ehl Contact

This paper investigates the influence of a transverse ridge on the film thickness in a circular EHL contact under rolling/sliding conditions. It is a numerical simulation of the optical EHL work of Kaneta et al. (1992). One of the purposes of this investigation is to check the validity of the algorithm and the Newtonian, isothermal lubricant assumption for film thickness predictions under these conditions (ph = 0.54 GPa). It will be shown that, both quantitatively, the film thickness on the central axis Y = 0, and qualitatively, the film thickness profile through “pseudo interference graphs”, the agreement between experiment and Newtonian isothermal theory is good. This supports the argument that the rheological and the thermal behavior of the fluid only slightly influence the film thickness and pressure distribution of the lightly loaded non-smooth contact case.

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Numerical Simulation for Air/Oil Separator of Aero-Engine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.510.197 ◽

2014 ◽

Vol 510 ◽

pp. 197-201

Author(s):

Ya Guo Lu ◽

Jian Ping Hu

Keyword(s):

Numerical Simulation ◽

Computational Models ◽

Separation Efficiency ◽

Impact Behavior ◽

Small Particles ◽

Minimum Diameter ◽

Oil Droplet ◽

Aero Engine ◽

Semi Empirical ◽

The Impact

Presently numerical simulation of separator is based on the assumption that all the droplets can be separated once they impinge the wall. However, large oil droplets may splash into small particles, which result in lower separation efficiency. A modified simulation model is presented in this paper to model the impact behavior of oil droplet. Some semi-empirical computational models are introduced to calculate the number and diameters of the secondary droplets. Then, the performance of a typical air/oil separator is predicted, including the separation efficiency and the minimum diameter. Results show that about the efficiency may reduce 1~2% due to the splash phenomena. While, no obvious difference is observed.

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