Vol.:(0123456789) 1 3
Journal of Thermal Analysis and Calorimetry
https://doi.org/10.1007/s10973-020-09825-2
CFD modeling and analysis of a two‑phase vapor separator
V. Vijayan
1
· M. Vivekanandan
2
· R. Venkatesh
3
· K. Rajaguru
1
· A. Godwin Antony
1
Received: 26 November 2019 / Accepted: 11 May 2020
© Akadémiai Kiadó, Budapest, Hungary 2020
Abstract
Vapor separator is a vital component in liquid-dominated steam feld equipment. While various designs exist, the currently
employed separator design was not so efective on separation and there is limitation in understanding the fuid behavior
within the separator. Challenges arise from the difculties in predicting the pressure distribution, fow regime and separation
efciency inside the separator vessel. Owing to this complexity, computational fuid dynamics (CFD) simulation of two-phase
fuid movement inside a vapor separator was carried out using Cosmos Express software package. The modifcations made
to the existing vapor separator were done considering the major mechanisms such as gravity separation, inertial separation,
centrifugal separation and surface tension force. This paper describes the CFD analysis of a modifed vapor separator model.
The design modifcation made in this vapor separator was to increase the efciency of the system by reducing its drawbacks.
The efect of turbulence and pressure drop on the existing vapor separator design was studied while improving their ef-
ciency to 100% and 99.5% in two diferent designs. The separator efciency was calculated by injecting water droplets after
a converged solution was achieved. Though, pressure drop inside the vapor chamber is higher (1344.91 N m
−2
) for the frst
design compared to later having a lower value of 817.68 N m
−2
. CFD simulation results demonstrated a promising method
to optimize the separator design.
Keywords Vapor separator · CFD · Cosmos Express · Turbulence
Introduction
A two-phase vapor separator is a device that separates vapor
from vapor–liquid mixture by means of density gradient.
Separation is enhanced by either centrifugal force or gravi-
tational force. Chemical processes are carried out by sepa-
ration and purifcation. Such separations mainly depend on
physical property diferences in the fuid stream. There are
two or more phases with diferent compositions in hetero-
geneous mixtures. The components of these mixtures do not
react chemically, and the boundaries of separation between
the diferent phases are clearly visible. These separations
are carried out with the aid of density diferences between
the phases. The position of separation units can be either
horizontal or vertical. Removal of liquids and solids from
a gas stream is vital in refning and gas processing applica-
tions. The contaminants should be removed from the vapor
to prevent the colliding of particles over the downstream
equipment such as compressor, turbine and burner, thus
reducing the cost of damage. Moreover, HCs and solid con-
taminants can consequently induce foaming in an amine
* V. Vijayan
vijayan.me@gmail.com
M. Vivekanandan
vivekbanu@gmail.com
R. Venkatesh
venkidsec@gmail.com
K. Rajaguru
rajaguruk.cad@gmail.com
A. Godwin Antony
eternal.tony@gmail.com
1
Mechanical Engineering Department, K. Ramakrishnan
College of Technology, Tiruchirappalli, Tamil Nadu, India
2
Department of Energy and Environment, National Institute
of Technology, Tiruchirappalli, Tamil Nadu, India
3
Mechanical Engineering Department, Kongunadu College
of Engineering and Technology, Tiruchirappalli, Tamil Nadu,
India