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Heat and Mass Transfer

, Volume 49, Issue 11, pp 1525–1533 | Cite as

Numerical and experimental study on parameters distribution inside a two-phase ejector

  • Bo ZhangEmail author
  • Jinsheng Lv
  • Yuanchao Wang
Original
  • 557 Downloads

Abstract

The two-phase flow process in an ejector was numerically and experimentally studied using R141b as a working fluid. A modified one-dimensional gas–liquid ejector model was proposed to remedy the defect in the traditional one. Gas–liquid boundary layer regions were discussed and used to close the model. Mac Cormack method is used to discrete controlling equations of gas–liquid two-phase flow in the ejector. The radial distribution of velocity and temperature, the variation of void fraction, the axial velocity variation and the influence of primary steam pressure on the mixing process were predicted with the numerical model. An experimental rig was set up to validate the model by comparing the experimental pressure distribution in the ejector with the calculating one.

Keywords

Void Fraction Annular Flow Boundary Layer Region Entrainment Ratio Boundary Layer Analysis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of symbols

a

Local sonic velocity (m/s)

A

Area (m2)

D

Diameter (m)

e

Specific intrinsic energy (kJ/kg)

F

Force (N)

h

Specific enthalpy (kJ/kg)

L

Total length of mixing chamber and diffuser (kJ/kg)

m

Mass flow rate (kg/s)

M

Mach number

P

Pressure (MPa)

R

Ejector entrainment ratio

R0

Entrance radius of mixing chamber (m)

T

Temperature (°C)

u

Axial velocity (m/s)

v

Radial velocity (m/s)

V

Specific volume (m3/kg)

X

Martinelli number

x

Axial distance (m)

y

Radial distance (m)

Re

Reynolds number

COP

Coefficient of performance

Greeks

μ

Dynamic viscosity (N·s/m2)

υ

Kinematic viscosity (m2/s)

α

Void fraction

ρ

Density (kg/m3)

γ

Adiabatic coefficient

Γ

Mass transfer rate (kg/m2·s)

Subscripts

c

Condenser

d

Discharge stream

e

Liquid nozzle entrance

g

Gas

l

Liquid

n

Primary nozzle exit

p

Primary steam

s

Secondary stream

0

Initial state of gas or liquid

Notes

Acknowledgments

This work is supported by projects of the National Natural Science Foundation of China (No. 51276025).

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.School of Energy and PowerDalian University of TechnologyDalianChina

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