scholarly journals The Results of Numerical Simulation of Two-Phase Liquid-Gas Flow with Constant and Real Thermodynamics Properties of the Liquid in a Shock-Jet Nozzle

2019 ◽  
pp. 51-60
Author(s):  
A.D. Khlopov ◽  
M.S. Frantsuzov
Keyword(s):  
Liquid Phase ◽  
Thermophysical Properties ◽  
Gas Flow ◽  
Volume Fraction ◽  
Temperature Dependent ◽  
Two Phase ◽  
Dispersion Process ◽  
Commercial Software Package ◽  
Phase Liquid ◽  
Jet Nozzle

In this paper, the outflow of liquid in the coflowing airstream from a shock-jet nozzle is examined using a commercial software package with varying initial and boundary conditions. Gas-dynamic characteristics and distribution fields for pressure, velocity, temperature and volume fraction of the two-phase flow are obtained. The influence of thermophysical properties of the liquid on the process of jet dispersion is determined. The results of simulation of the liquid outflow from the shock-jet nozzle at constant and real (temperature dependent) thermophysical properties of the liquid phase are compared. The qualitative and quantitative influence of the input pressure in the nozzle on the jet dispersion process is determined. As a result of a series of calculations, the minimum required characteristics of temporal and spatial resolution for the correct solution of the problem are identified. It is established that the volume content of the liquid phase is higher with real thermophysical properties compared to the constant ones.

scholarly journals Axial dispersion of the liquid phase on a three-phase Karr reciprocating plate column

2004 ◽  
Vol 69 (7) ◽  
pp. 581-599 ◽  
Author(s):  
Ljubisa Nikolic ◽  
Vesna Nikolic ◽  
Vlada Veljkovic ◽  
Miodrag Lazic ◽  
Dejan Skala
Keyword(s):  
Liquid Phase ◽  
Gas Flow ◽  
Dispersion Coefficient ◽  
Solid Phase ◽  
Axial Dispersion ◽  
Two Phase ◽  
Three Phase ◽  
Phase Liquid ◽  
Similar Equation ◽  
Plate Column

The influence of the gas flow rate and vibration intensity in the presence of the solid phase (polypropylene spheres) on axial mixing of the liquid phase in a three phase (gas-liquid-solid) Karr reciprocating plate column (RPC) was investigated. Assuming that the dispersionmodel of liquid flow could be used for the real situation inside the column, the dispersion coefficient of the liquid phase was determined as a function of different operating parameters. For a two-phase liquid-solid RPC the following correlation was derived: DL = 1.26(Af)1.42 UL 0.51 ?S 0.23 and a similar equation could be applied with ? 30 % confidence for the calculation of axial dispersion in the case of a three-phase RPC: DL = 1.39(Af)0.47 UL0.42UG0.03 ?S -0.26.

scholarly journals Thermodynamics and Machine Learning Based Approaches for Vapor–Liquid–Liquid Phase Equilibria in n-Octane/Water, as a Naphtha–Water Surrogate in Water Blends

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 413
Author(s):  
Sandra Lopez-Zamora ◽  
Jeonghoon Kong ◽  
Salvador Escobedo ◽  
Hugo de Lasa
Keyword(s):  
Machine Learning ◽  
Liquid Phase ◽  
Phase Equilibria ◽  
Aspen Plus ◽  
Phase Region ◽  
Two Phase ◽  
Technical Literature ◽  
Phase Liquid ◽  
Liquid Vapor ◽  
Vapor Liquid

The prediction of phase equilibria for hydrocarbon/water blends in separators, is a subject of considerable importance for chemical processes. Despite its relevance, there are still pending questions. Among them, is the prediction of the correct number of phases. While a stability analysis using the Gibbs Free Energy of mixing and the NRTL model, provide a good understanding with calculation issues, when using HYSYS V9 and Aspen Plus V9 software, this shows that significant phase equilibrium uncertainties still exist. To clarify these matters, n-octane and water blends, are good surrogates of naphtha/water mixtures. Runs were developed in a CREC vapor–liquid (VL_ Cell operated with octane–water mixtures under dynamic conditions and used to establish the two-phase (liquid–vapor) and three phase (liquid–liquid–vapor) domains. Results obtained demonstrate that the two phase region (full solubility in the liquid phase) of n-octane in water at 100 °C is in the 10-4 mol fraction range, and it is larger than the 10-5 mol fraction predicted by Aspen Plus and the 10-7 mol fraction reported in the technical literature. Furthermore, and to provide an effective and accurate method for predicting the number of phases, a machine learning (ML) technique was implemented and successfully demonstrated, in the present study.

scholarly journals Collisions of Two-Phase Liquid Droplets in a Heated Gas Medium

Entropy ◽  
2021 ◽  
Vol 23 (11) ◽  
pp. 1476
Author(s):  
Pavel Tkachenko ◽  
Nikita Shlegel ◽  
Pavel Strizhak
Keyword(s):  
Volume Fraction ◽  
Industrial Applications ◽  
Droplet Breakup ◽  
Liquid Volume ◽  
Liquid Droplets ◽  
Vapor Bubbles ◽  
Two Phase ◽  
Relative Volume Fraction ◽  
Phase Liquid ◽  
Gas Medium

The paper presents the experimental research findings for the integral characteristics of processes developing when two-phase liquid droplets collide in a heated gas medium. The experiments were conducted in a closed heat exchange chamber space filled with air. The gas medium was heated to 400–500 °C by an induction system. In the experiments, the size of initial droplets, their velocities and impact angles were varied in the ranges typical of industrial applications. The main varied parameter was the percentage of vapor (volume of bubbles) in the droplet (up to 90% of the liquid volume). The droplet collision regimes (coalescence, bounce, breakup, disruption), size and number of secondary fragments, as well as the relative volume fraction of vapor bubbles in them were recorded. Differences in the collision regimes and in the distribution of secondary fragments by size were identified. The areas of liquid surface before and after the initial droplet breakup were determined. Conditions were outlined in which vapor bubbles had a significant and, on the contrary, fairly weak effect on the interaction regimes of two-phase droplets.

The 3-D Finite Element Analysis on Elastic-Plastic Micromechanical Response of the Particle Volume Fraction

2019 ◽  
Vol 962 ◽  
pp. 210-217
Author(s):  
Yong Ming Guo ◽  
Nozomi Fukae
Keyword(s):  
Volume Fraction ◽  
Particle Volume Fraction ◽  
Three Dimensional ◽  
Particle Volume ◽  
Two Phase ◽  
Element Analysis ◽  
Elastic Plastic ◽  
Microstructural Parameters ◽  
Commercial Software Package ◽  
Properties Of Materials

It is well known that the properties of materials are a function of their microstructural parameters. The FEM is a good selection for studies of three-dimensional microstructure-property relationships. In this research, the elastic-plastic micromechanical response of the particle volume fraction of two-phase materials have been calculated using a commercial software package of the FEM, some new knowledges on the microstructure-property relationships have obtained.

EQUILIBRIUM VELOCITY DISTRIBUTION FUNCTIONS FOR A KINETIC MODEL OF TWO-PHASE FLOWS

1995 ◽  
Vol 05 (02) ◽  
pp. 191-211 ◽  
Author(s):  
LIONEL SAINSAULIEU
Keyword(s):  
Velocity Distribution ◽  
Gas Flow ◽  
Stokes Equations ◽  
Volume Fraction ◽  
Velocity Distribution Function ◽  
Distribution Functions ◽  
Solid Particles ◽  
Navier Stokes ◽  
Two Phase ◽  
Entropy Balance

We consider a cloud of solid particles in a gas flow. The cloud is described by a probability density function which satisfies a kinetic equation. The gas flow is modeled by Navier-Stokes equations. The two phases exchange momentum and energy. We obtain the entropy balance of the gas flow and deduce some bounds for the volume fraction of the gas phase. Writing the entropy balance for the dispersed phase enables one to determine the particles equilibrium velocity distribution function when the gas flow is known.

scholarly journals Steady and unsteady fluidised granular flows down slopes

2017 ◽  
Vol 827 ◽  
pp. 67-120 ◽  
Author(s):  
D. E. Jessop ◽  
A. J. Hogg ◽  
M. A. Gilbertson ◽  
C. Schoof
Keyword(s):  
Gas Flow ◽  
Numerical Solutions ◽  
Volume Fraction ◽  
Granular Flows ◽  
Similarity Solutions ◽  
Two Phase ◽  
Basal Resistance ◽  
Front Position ◽  
Theoretical Predictions ◽  
Asymptotic Reduction

Fluidisation is the process by which the weight of a bed of particles is supported by a gas flow passing through it from below. When fluidised materials flow down an incline, the dynamics of the motion differs from their non-fluidised counterparts because the granular agitation is no longer required to support the weight of the flowing layer. Instead, the weight is borne by the imposed gas flow and this leads to a greatly increased flow mobility. In this paper, a framework is developed to model this two-phase motion by incorporating a kinetic theory description for the particulate stresses generated by the flow. In addition to calculating numerical solutions for fully developed flows, it is shown that for sufficiently thick flows there is often a local balance between the production and dissipation of the granular temperature. This phenomenon permits an asymptotic reduction of the full governing equations and the identification of a simple state in which the volume fraction of the flow is uniform. The results of the model are compared with new experimental measurements of the internal velocity profiles of steady granular flows down slopes. The distance covered with time by unsteady granular flows down slopes and along horizontal surfaces and their shapes are also measured and compared with theoretical predictions developed for flows that are thin relative to their streamwise extent. For the horizontal flows, it was found that resistance from the sidewalls was required in addition to basal resistance to capture accurately the unsteady evolution of the front position and the depth of the current and for situations in which sidewall drag dominates, similarity solutions are found for the experimentally measured motion.

Sign in / Sign up

Export Citation Format

Share Document