Leakage Characteristics of Scroll Compressor by Two Phase Flow Model in Consideration of Wall Oil Film Thickness.

The lubrication and heat transfer designs of bearing chamber depend on an understanding of oil/air two-phase flow. As initial and boundary conditions, the characteristics of ligament and droplet generation by oil film on rotating parts have significant influence on the feasibility of oil/air two-phase flow analysis. An integrated model to predict the oil film flow, ligament number, and droplet Sauter mean diameter (SMD) of a rotating disk, which is an abstraction of the droplet generation sources in a bearing chamber, is developed based on the oil film force balance analysis and wave theory. The oil film thickness and velocity, ligaments number, and droplet SMD are calculated as functions of the rotating disk radius, rotational speed and oil volume flow rate and oil properties. The theoretical results show that the oil film thickness and SMD are decreased with an increasing rotational speed, while the radial, transverse velocities, and ligament number are increased. The oil film thickness, radial velocity, and SMD are increased with an increasing oil flow rate, but the transverse velocity and ligament number are decreased. A test facility is built for the investigation into the ligament number of a rotating disk, and the measurement of ligament number is carried out by means of a high speed photography.

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Comprehensive Comparisons of a Two-Phase Flow Model with a Wide Range of Conditions

Coastal Dynamics 2005 ◽

10.1061/40855(214)91 ◽

2006 ◽

Author(s):

Haijiang Liu ◽

Shinji Sato

Keyword(s):

Flow Model ◽

Two Phase Flow ◽

Phase Flow ◽

Two Phase ◽

Wide Range

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A ONE-DIMENSIONAL TWO-PHASE FLOW MODEL AND EXPERIMENTAL VALIDATION FOR A FLASHING VISCOUS LIQUID IN A SPLASH PLATE NOZZLE

Atomization and Sprays ◽

10.1615/atomizspr.2015011460 ◽

2015 ◽

Vol 25 (9) ◽

pp. 795-817 ◽

Cited By ~ 1

Author(s):

Mika P. Jarvinen ◽

A. E. P. Kankkunen ◽

R. Virtanen ◽

P. H. Miikkulainen ◽

V. P. Heikkila

Keyword(s):

Viscous Liquid ◽

Experimental Validation ◽

Flow Model ◽

Two Phase Flow ◽

Phase Flow ◽

Two Phase ◽

One Dimensional

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Status of Advanced Two-Phase Flow Model Development for SRM Chamber Flow Field and Combustion Modeling

10.21236/ada427829 ◽

2004 ◽

Author(s):

Gary Luke ◽

Mark Eagar ◽

Michael Sears ◽

Scott Felt ◽

Bob Prozan

Keyword(s):

Flow Field ◽

Flow Model ◽

Two Phase Flow ◽

Model Development ◽

Phase Flow ◽

Two Phase ◽

Combustion Modeling

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Experimental Investigation and Prediction on Pressure Drop during Flow Boiling in Horizontal Microchannels

Micromachines ◽

10.3390/mi12050510 ◽

2021 ◽

Vol 12 (5) ◽

pp. 510

Author(s):

Yan Huang ◽

Bifen Shu ◽

Shengnan Zhou ◽

Qi Shi

Keyword(s):

Pressure Drop ◽

Flow Model ◽

Two Phase Flow ◽

Flow Boiling ◽

Separated Flow ◽

Heat Fluxes ◽

Phase Flow ◽

Vapor Quality ◽

Two Phase ◽

Gas Flux

In this paper, two-phase pressure drop data were obtained for boiling in horizontal rectangular microchannels with a hydraulic diameter of 0.55 mm for R-134a over mass velocities from 790 to 1122, heat fluxes from 0 to 31.08 kW/m2 and vapor qualities from 0 to 0.25. The experimental results show that the Chisholm parameter in the separated flow model relies heavily on the vapor quality, especially in the low vapor quality region (from 0 to 0.1), where the two-phase flow pattern is mainly bubbly and slug flow. Then, the measured pressure drop data are compared with those from six separated flow models. Based on the comparison result, the superficial gas flux is introduced in this paper to consider the comprehensive influence of mass velocity and vapor quality on two-phase flow pressure drop, and a new equation for the Chisholm parameter in the separated flow model is proposed as a function of the superficial gas flux . The mean absolute error (MAE ) of the new flow correlation is 16.82%, which is significantly lower than the other correlations. Moreover, the applicability of the new expression has been verified by the experimental data in other literatures.

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A prospective study of anti-vibration mechanism of microfluidic fuel cell via novel two-phase flow model

Energy ◽

10.1016/j.energy.2020.119543 ◽

2021 ◽

Vol 218 ◽

pp. 119543

Author(s):

Jingxian Chen ◽

Peihang Xu ◽

Jie Lu ◽

Tiancheng Ouyang ◽

Chunlan Mo

Keyword(s):

Fuel Cell ◽

Prospective Study ◽

Flow Model ◽

Two Phase Flow ◽

Phase Flow ◽

Two Phase ◽

Vibration Mechanism ◽

Microfluidic Fuel Cell ◽

A Prospective Study

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A relaxation scheme for a hyperbolic multiphase flow model

ESAIM Mathematical Modelling and Numerical Analysis ◽

10.1051/m2an/2019034 ◽

2019 ◽

Vol 53 (5) ◽

pp. 1763-1795 ◽

Cited By ~ 1

Author(s):

Khaled Saleh

Keyword(s):

Multiphase Flow ◽

Flow Model ◽

Two Phase Flow ◽

Equations Of State ◽

Energy Inequality ◽

Approximation Error ◽

Finite Volume Scheme ◽

Phase Flow ◽

Two Phase ◽

Relaxation Scheme

This article is the first of two in which we develop a relaxation finite volume scheme for the convective part of the multiphase flow models introduced in the series of papers (Hérard, C.R. Math. 354 (2016) 954–959; Hérard, Math. Comput. Modell. 45 (2007) 732–755; Boukili and Hérard, ESAIM: M2AN 53 (2019) 1031–1059). In the present article we focus on barotropic flows where in each phase the pressure is a given function of the density. The case of general equations of state will be the purpose of the second article. We show how it is possible to extend the relaxation scheme designed in Coquel et al. (ESAIM: M2AN 48 (2013) 165–206) for the barotropic Baer–Nunziato two phase flow model to the multiphase flow model with N – where N is arbitrarily large – phases. The obtained scheme inherits the main properties of the relaxation scheme designed for the Baer–Nunziato two phase flow model. It applies to general barotropic equations of state. It is able to cope with arbitrarily small values of the statistical phase fractions. The approximated phase fractions and phase densities are proven to remain positive and a fully discrete energy inequality is also proven under a classical CFL condition. For N = 3, the relaxation scheme is compared with Rusanov’s scheme, which is the only numerical scheme presently available for the three phase flow model (see Boukili and Hérard, ESAIM: M2AN 53 (2019) 1031–1059). For the same level of refinement, the relaxation scheme is shown to be much more accurate than Rusanov’s scheme, and for a given level of approximation error, the relaxation scheme is shown to perform much better in terms of computational cost than Rusanov’s scheme. Moreover, contrary to Rusanov’s scheme which develops strong oscillations when approximating vanishing phase solutions, the numerical results show that the relaxation scheme remains stable in such regimes.

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