International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 08 | Aug -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 961
ANALYSIS OF DOUBLE PIPE HEAT EXCHANGER WITH HELICAL FINS
Bandu A.Mule
1
, Prof.D.N.Hatkar
2
,Prof.M.S.Bembde
3
1
ME student, Department of Mechanical Engineering, MGM’s COE, Nanded, Maharashtra, India.
2
Professor, Department of Mechanical Engineering, MGM’s COE, Nanded, Maharashtra, India.
3
Professor, Department of Mechanical Engineering, TCOE, Nerul, Mumbai, Maharashtra, India.
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Abstract – In this present day double pipe heat exchanger
is the most common type of heat exchanger widely use in
oil refinery and other large chemical processes because it
suits high pressure application. To determine the
performance of double pipe heat exchanger, the hot fluid
has made to flow through inner tubes and cold fluid is flow
through the outer tubes. The main objective is to design
the DPHE with different angles of fins. & to study the flow
and temperature field inside the tubes. Also, attempts
were made to investigate the effects and heat transfer
characteristics of a DPHE for six different inclination of
fins namely 0 , 5 , 10 T
of DPHE has made by using CATIA V5 and meshing is
generated by using hyper mesh. The flow and temperature
field inside the tube have studied using ANSYS FLUENT
R18.0. The work determines with better enhancements in
heat transfer rate and overall heat transfer coefficient
using helical fins.
Key Words: Helical fins, overall heat transfer coefficient,
heat transfer rate, mass flow rate, CFD.
1. INTRODUCTION
The heat exchanger is a device used to transfer the heat
from the hot fluid to cold fluid with maximum rate and
minimum investment. The heat exchanger is an important
device in various thermal systems for e.g. condenser and
evaporator in refrigeration systems, boiler & condenser in
steam power plants etc. The heat exchanger has wide
variety of industrial applications such as process
industries, chemical industries, food industries etc. Now
there is need of the compact heat exchangers to give
required heat transfer rate with minimum space
requirement. The helical fins on the inner tube increase
the area available for the heat transfer and the helical fins
on inner tube increases the turbulence. With helical fins at
larger pitch, the efficiency of the heat transfer
enhancement however is rather low when the total length
of heat exchanger is fixed. At high Reynolds number,
pressure drop will increase sharply if the helical pitch
decreases. Due to this reason the heat transfer
enhancement with helical fins is more suitable at low
Reynolds number. The worldwide researchers are making
hard efforts to find out suitable alternatives for heat
exchangers with different geometry and varying
parameters which effects on performance of heat
exchanger. Now days helix fins has became blessings for
researchers. Balarama Kundu et al. [1] had
experimentation on beneficial design of shell and tube
heat exchangers for attachment of longitudinal fins with
trapezoidal profile. In this experimentation, the
rectangular and trapezoidal fin shapes longitudinally
attached to the fin tubes. The results show that the heat
transfer rate was lesser than the rectangular cross section
keeping the outer shell diameter is a constant along with
all other constraints of a heat exchanger. N. Sathiya
Narayanan et al. [2] had done modelling and simulation of
helical fluid flow through double start screw type heat
exchanger. In this experimentation efficient heat transfer
is achieved by increasing the area of heat transfer by
providing fin arrangement. The result shows that an
efficient heat transfer is achieved as heat transfer
coefficient is more. Shewale omkar M et.al. [3] have
performed experimental investigation of double pipe heat
exchanger with helical fins on the inner rotating tube. In
this analysis the Nusselt Number obtained from the
experimental results are higher than that of theoretical
values obtained from Dittus-Boelter equation. The helical
fins over the inner tube results into the increase in the
heat transfer area and reduction in the hydraulic diameter
of the flow channel. The result shows that the Nusselt
number for the inner tube with helical fins is 4 times
higher than that of the plain inner tube for stationary
condition. The Nusselt number at the speed 50 rpm and
100 rpm are 36 % and 64% more than that of stationary
inner tube. Vinous M Hameed et al. [4] have carried out an
experimental study of turbulent flow heat transfer and
pressure loss in a double pipe heat exchanger with
triangular fins. The working fluids were air flowing in the
annular pipe and water through the inner circular tube.
The results shows that the heat dissipation 3.815 to
5.405times than that of smooth tube. . In the lowest space
the average increment in nusselt number is about 98%
over the smooth tube heat exchanger. Yu et al. [5]
performed to compute the heat transfer and pressure drop
characteristics of tubes with internal wave-like
longitudinal fins. They conducted two cases for this work
were carefully examined, using air as a working fluid. For
the tube of type A, since the inner channel of the insertion
is not blocked, its flow cross-section area only differs
mildly from that without the insertion. While for the tube
of type B the cross-section of the inner tube is totally
blocked. The wave-like fins are within the annulus and
span its full width. There are total 20 waves. The outer
tube was electrically heated. Pressure taps were no