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Design and air flow analysis in intake manifold with different cross section
using CFD

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 International Journal of Innovative Technology and Exploring Engineering (IJITEE)
ISSN: 2278-3075, Volume-8 Issue-4, February 2019

Design and Air Flow Analysis in Intake

Manifold with Different Cross Section Using
CFD
K. Sathishkumar, R. Soundararajan, G. Dinesh, S. Surjith


Abstract: The air-fuel mixture is the important source in engine II. LITERATURE REVIEW
combustion, the transfer of air-fuel mixture is done by intake
manifold in the intake system of the automobile. So due to The intake manifold is designed with fillet on the corner in
improving the efficiency of the engine most of the automobile order to avoid the formation of turbulence, by using CFD the
manufacturing industry is mainly focused on the intake manifold existing model and the proposed model is tested to check the
design for better performance. This project investigates about flow flow of air inside the manifold, the author had concluded that
analysis taken in the different cross-section of an intake manifold. the proposed will distribute the pressure evenly and it may
The main goal of our work is to change the cross-section of the also neglect the formation of turbulence in the manifold the
intake manifold and analysis the model. In this paper, the velocity vector is compared in both the models[1].CFD
manifold is designed by considering two different cross-section
one is the circular outlet and the other is the convergent-divergent
analysis is done on Ford two valve production engine, and the
outlet and the created model is analyzed. The flow analysis is author had done the same test in experimentally by using
carried by using CFD and the values are compared and the best Ricardo MK-3 engine and he concludes the result by
cross-section is concluded. The manifold with a comparing both experimental and software results and
convergent-divergent outlet has high velocity when compared with summarize the manual method is a worthwhile goal [2,]. An
the circular outlet. The intake manifold can be used in automobile experimental test on intake manifold is conducted for taking
industries. the engine performance such as brake power, torque, specific
Keywords: Air intake manifold, Convergent-divergent outlet fuel consumption, thermal efficiency, brake indicated power
manifold, Airflow, Fluent, Circular manifold, CFD. and C02 Emission, as a result, the intake plenum volume
increased, intake manifold pressure is also increased, and the
I. INTRODUCTION mixture became Leaner and pollutant is decreased due to the
increase in relative air ratio [4]. In this paper, the author had
In a vehicle, the transfer of air-fuel is taken by intake
the design and manufacture of an intake system for the 600cc
manifold to the combustion chamber, so hence the manifold is
formula society of automotive engineer’s engine. Owing to
one of the critical parts in an automobile. The main function
the inherent geometric constraints imposed by the existing
of the intake manifold is to distribute the air equally to each
manufacturing process, the manufacturing of inlet manifold is
cylinder head at the stage of combustion. In most of the
done by FDM by consist of the plenum, plenum elbow, and
research papers to improve the engine performance, the
Engine. The main aim of the work is to enhance the charge
dimension of the plenum is varied and the analysed is done
distribution, for improving the torque in overall process by
using CFD. While modifying the design of the manifold the
using low-density materials such as hose clamps and silicon
formation of turbulence should be strictly avoided. In this
couples in the production of the aluminum counterpart [6].
project, the outlet of the manifold is designed in different
The author had done a flow test on the numerical created
cross section and the air flow is analysed and the velocities are
model of the intake manifold, the CFD analysis is carried by
compared with the circular cross-section. In order to avoid the
taking standard kee turbulence model, by solving the Navier
formation of turbulence the edges are filleted and the flow is
stroke equation in the CFD flow work. And the author has also
carried out to check the turbulence formation.
done experimental measurements to test the brake power,
The CFD test is carried in both the cross section manifold
brake torque, and brake thermal Efficiency. As a result of the
by considering three different cases one is by opening of all
proposed model, there is an increase in 16% in brake power,
outlet of the manifold, the second condition is by taking 1&3
13.9% improvement in brake torque and finally 12.5%
cylinders are open and 2&4 cylinders are in closed condition,
increase in their brake thermal efficiency. Due to the
and the final condition is by taking 1&3 cylinder is in closed
improvement in their parameters, there is a decrease in 28%
Condition and 2&4 cylinders are in open condition. Each
of brake specific fuel consumption (BSFC). So the author had
condition is tested and the values are discussed and the best
concluded that the proposed design will give better
cross-section is concluded.
performance [7]. Design and produce a spiral intake system
by additive manufacturing technique and to place the spiral
Revised Manuscript Received on 8 February 2019. intake manifold in the engine to do necessary experimental
K.Sathishkumar, PG Student, Department of Mechanical Engg, Sri techniques by installing the engine on the test rig and
Krishna College of Engineering and Technology, Coimbatore, TN, India. compared with the old manifold system, as a result of spiral
R.Soundararajan*, Associate Professor, Department of Mechanical
Engg, Sri Krishna College of Engineering and Technology, Coimbatore, TN, manufacturing product the volumetric efficiency was
India. increased this is because of the size and shape of the manifold,
G.Dinesh, UG Student, Department of Mechanical Engg, Sri Krishna
College of Engineering and Technology, Coimbatore, TN, India.
S.Surjith, UG Student, Department of Mechanical Engg, Sri Krishna
College of Engineering and Technology, Coimbatore, TN, India.

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& Sciences Publication
 Design and Air Flow Analysis in Intake Manifold with Different Cross Section Using CFD

This the spiral intake manifold plays a direct impact on the

volumetric efficiency [8]. Three different kinds of intake
manifold are designed and analysed and compare their results
and also done an experiment analysis and conclude the best
design series in this paper. The intake manifold with vertical
intake will give the better performance and the EGR
distribution is also increases by 14% when it is compared with
horizontal intake and the experimental results are more
nearest to the CFD analysis results [11]. In this paper, the
intake manifold is designed using solid works and the model
is analysed using Ansys CFD. In most of the cases, the
analysis is done only by changing the plenum length and area
Fig. 2 Manifold with Convergent-Divergent outlets
of the intake manifold, the current project is based on keeping
the manifold plenum length as constant and the outlet cross
IV. ANALYSIS USING CFD FLUENT
section is changed and the analysis is done by keeping the
boundary condition as same in all models. The air intake manifold is designed and the designed model
is imported into Ansys software for doing analysis, in this by
III. DESIGN OF AIR INTAKE MANIFOLD using fluent the air flow analysis is done on Ansys workbench
18.2. The three different cases of the condition are taken to do
The 3D model of the intake manifold is designed using fluent analysis they are,
Solid works2016 software. For create a model of the intake
manifold, the following things should be considered: 1.All outlets are open
2.Outlets 1,3 are open and Outlets 2,4 are close
1. Uniform distribution of air pressure to all the 3.Outlets 1,3 are close and Outlets 2,4 are open
engine cylinders in order to overcome the uncompleted
combustion. A computational fluid element (CFD) is the utilization of
2. Proper designs of intake manifold profile helps to mathematical equation, material science, and computational
reduce the sudden raise in pressure waves which improve programming to show how a gas or fluid streams in any area.
induction process and also eliminate the unnecessary Computational fluid elements based upon the Navier-Stokes
turbulence and eddies inside the intake manifold. conditions. These conditions depict how the speed, weight,
temperature, and thickness of a moving fluid are associated.
By solving the input parameters using Navier-strokes
equations the required outputs are taken. So all the analysis is
done and each analysis is explained and the values are
tabulated below. To check the flow of the fluid on the intake
manifold the following boundary conditions are considered
on the CFD fluent, the fluid used for the analysis is taken as
air, the density of the fluid is 1.225 kg/m3, the viscosity of the
fluid can be taken as 1.7894x10^-5 kg/m-s, the outlet pressure
is taken as 1 atmospheric pressure, and the temperature of the
fluid is given as 300k and the solver is selected as pressure
based solver , the residual value or the convergent limit is
given as 1e-6 and finally the K- ε standard wall function is
taken as the Mathematical models for analysis. The boundary
condition is given based on the application and the inlet
velocity is taken as 30m/s. After all the necessary conditions
Fig. 1 Manifold with Circular outlets
are given the total number of iteration is mentioned to start the
In this design the inlet valve is taken as 40mm diameter, the analysis.
outlet valve diameter is taken as 25mm and the plenum length
is taken as 100mm, this is for a circular manifold and for the V. CFD SIMULATION
convergent-divergent manifold the inlet and plenum length is
A. All Outlets are open
taken as same and the outlet valve is taken as a
convergent-divergent type. In this the convergent angle is Once the meshing is completed the mesh file is imported in
given as 12o and the divergent angle is taken as 6o and the the fluent database, in the fluent database the mesh size, mesh
throat diameter is given as 20mm, so by this input parameter, quality, and mesh aspect ratio are checked and the necessary
the two different types of the manifold are designed using input conditions are given. In this analysis, all the outlets are
solid works 2016. taken as an open condition so the air flows from the inlet to all
four-cylinder outlet equally.

Published By:
Blue Eyes Intelligence Engineering
Retrieval Number: D2850028419/19©BEIESP 707 & Sciences Publication
 International Journal of Innovative Technology and Exploring Engineering (IJITEE)
ISSN: 2278-3075, Volume-8 Issue-4, February 2019

The flow analysis is done and the results are taken using B. Outlets 1, 3 are open and Outlets 2,4 are close
CFD post-processing, the figure 3-4 gives the pressure
In this condition the CFD analysis is done based on the
contour of the manifold and the figure 5-6 gives the velocity
sequence, that the outlets 1 & 3 are taken as open condition
contour of the manifold in open outlet condition.
and the outlets 2 & 4 are taken as close condition in order to
close the flow the outlets 2 & 4 are given as wall and the
outlets 1& 3 are given as outlet in the named section. By
giving all necessary boundary conditions the inlet velocity is
given and the number of iteration is run using the fluent
database. The flow analysis is done and the results are taken
using CFD post-processing, the figure 7-8 gives the pressure
contour of the manifold and the figure 9-10 gives the velocity
contour of the manifold in the given condition.

Fig. 3 Pressure Contour of Circular manifold with all

open outlets

Fig. 7 Pressure Contour of Circular manifold with 1,3

open & 2,4 close

Fig. 4 Pressure Contour of Convergent-Divergent

manifold with all open outlets

Fig. 8 Pressure Contour of Convergent-Divergent

manifold with 1,3 open & 2,4 close

Fig. 5 Velocity Contour of Circular manifold with all

open outlets

Fig. 9 Velocity Contour of Circular manifold with 1,3

open & 2,4 close

Fig. 6 Velocity Contour of Convergent-Divergent

manifold with all open outlets

Published By:
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& Sciences Publication
 Design and Air Flow Analysis in Intake Manifold with Different Cross Section Using CFD

Fig. 10 Velocity Contour of Convergent-Divergent Fig. 13 Velocity Contour of Circular manifold with 1,3
manifold with 1, 3 open & 2, 4 close close & 2,4 open
C. Outlets 1,3 are close and Outlets 2,4 are open
In this condition the CFD analysis is done based on the
sequence, that the outlets 1 & 3 are taken as close condition
and the outlets 2 & 4 are taken as open condition in order to
stop the flow the outlets 1 & 3 are given as wall and the outlets
2 & 4 are given as outlet in the named section. By giving all
necessary boundary conditions the inlet velocity is given and
the number of iteration is run using the fluent database. The
flow analysis is done and the results are taken using CFD
post-processing, the figure 11-12 gives the pressure contour
of the manifold and the figure 13-14 gives the velocity
contour of the manifold in the given condition.

Fig. 14 Velocity Contour of Convergent-Divergent

manifold with 1,3 close & 2,4 open

VI. RESULT AND DISCUSSION

Using CFD analysis flow characteristics are studied at the
different cross-section of intake manifold the cylinder. The
various parameters such as velocity, pressure are analysed. By
using CFD post-processing the various results are taken at
each domain and the values are tabulated below. The
improvements in each manifold cross-section are compared
by the results in the CFD post-processing.
Fig. 11 Pressure Contour of Circular manifold with 1,3
close & 2,4 open
Pressure in Pa
Conditions
Existing Model Proposed Model
All open outlets
802.007 880.9
Outlets 1,3 Open
566.4 819.3
& 2,4 Close
Outlets 1,3 Close
575.2 648.6
& 2,4 Open

Table 1 Pressure Contour of the Manifold

Fig. 12 Pressure Contour of Convergent-Divergent
manifold with 1,3 close & 2,4 open

Published By:
Blue Eyes Intelligence Engineering
Retrieval Number: D2850028419/19©BEIESP 709 & Sciences Publication
 International Journal of Innovative Technology and Exploring Engineering (IJITEE)
ISSN: 2278-3075, Volume-8 Issue-4, February 2019

convergent-divergent model. In the existing model, there is a

constant pressure is maintained but in the proposed model the
pressure of the manifold is changed at each section, due to the
changes the flow of air may be varied in the proposed model.
So the proposed model gives more performance when
compared to the existing model.

VII. CONCLUSION
Subsequent from reviewing work of various research
authors as above it can be effectively presumed that intake
manifold had an extensive effect on automobile engines. On
Fig. 15 Pressure Changes at Different Conditions seeing the results the CFD analysis is done in three different
From the above figure, we can easily conclude that the conditions in the second condition based on the firing order,
pressure is changed at each condition based on the the velocity of the air improves by 8.11% of the flow speed
geometrical structure of the manifold. On seeing the table 1, when compared with the existing design. In the third
we came to conclude that there is a rise in pressure on the condition, the total velocity is improved by 8.48% from the
proposed model when it compared with the existing model. existing value. We can clearly understand that intake
This pressure difference will be taken due to the change in the manifold with convergent-divergent outlet has maximum
area of the outlet in the manifold, in the convergent-divergent velocity when it compared with the circular outlet. Our
proposed design has achieved a better performance compared
manifold the area is reduced in the convergent section and
with the existing model. The small changes in velocity will
there is a constant area maintained in the throat section and
give better combustion in the engine and it also improves the
the area is increased in the divergent section. So due to the
engine performance so we concluded that the
increase in area on the divergent section when compared to convergent-divergent manifold outlet gives the best result.
the convergent section the pressure is increased in the
divergent section of the outlet. On seeing the existing model REFERENCES
of the manifold there is a constant area maintained on the
1. Anilkumar. D.B, Dr. Anoop Kumar Elia , Computational analysis of
outlet so there is no increase in pressure. By comparing both Intake manifold design of a four cylinder diesel engine in Technical
model the proposed model has a change in pressure research organization,5(4), 2018.
difference. 2. Wolf Bauer and John B. Heywood, Oshin Avanessian and Derlon Chu
, Flow Characteristics in Intake Port of Spark Ignition Engine
Velocity in m/s Investigated by CFD and Transient Gas Temperature Measurement in
Conditions SAE technical paper series 961997.
3. V. Bellenger , A. Tcharkhtchi , Ph. Castaing , Thermal and mechanical
Existing Model Proposed Model fatigue of a PA66/glass fibers composite material in ELSEVIER
International Journal of Fatigue 28 (2006) pp.1348–1352.
All open outlets 4. M.A. Ceviz , Intake plenum volume and its influence on the engine
33.86 33.80
performance, cyclic variability and emissions in ELSEVIER Energy
Outlets 1,3 Open Conversion and Management 48 (2007) pp.961–966 .
50.83 54.95 5. M.A. Ceviz , M. Akin , Design of a new SI engine intake manifold with
& 2,4 Close
variable length plenum in ELSEVIER Energy Conversion and
Management 51 (2010) pp.2239–2244 .
Outlets 1,3 Close
50.96 55.28 6. Ryan Ilardo , Christopher B. Williams, Design and manufacture of a
& 2,4 Open Formula SAE intake system using fused deposition modeling and
fiber-reinforced composite materials in Rapid Prototyping Journal,
16(3), pp. 174 – 179.
Table 2 Velocity Contour of the Manifold
7. Mohamed Ali Jemni, Gueorgui Kantchev, Mohamed Salah Abid ,
Influence of intake manifold design on in-cylinder flow and engine
performances in a bus diesel engine converted to LPG gas fuelled,
using CFD analyses and experimental investigations in ELSEVIER
Energy 36 (2011) pp.2701-2715.
8. A.Manmadhachary, M.Santosh kumar , Y.Ravi kumar ,
Design&manufacturing of spiral intake manifold to improve Volument
efficiency of injection diesel engine byAM process in 5th International
Conference of Materials Processing and Characterization (ICMPC
2016) pp. 1084–1090.
9. M. Safari , M. Ghamari and A. Nasiritosi , Intake Manifold
Optimization by Using 3-D CFD Analysis in SAE technical paper
series 2003-32-0073.
10. Robert M. Siewert, Roger B. Krieger, Mark S. Huebler, Prafulla C.
Baruah and Bahram Khalighi and Markus Wesslau , Modifying an
Intake Manifold to Improve Cylinder-to-Cylinder EGR Distribution in
Fig. 16 Velocity Changes at Different Conditions a DI Diesel Engine Using Combined CFD and Engine Experiments in
SAE technical paper series 2001-01-3685.
On seeing the velocity, table 2 will clearly explain the
velocity of the manifold in each condition. In this, the velocity
of the air is increased due to the increases in pressure, by
comparing the result of both models there is an increase in
velocity at the outlet of the manifold in the

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 Design and Air Flow Analysis in Intake Manifold with Different Cross Section Using CFD

11. Jianmin Xu , Flow analysis of engine intake manifold based on

computational fluid dynamics in IOP Conf. Series: Journal of Physics:
Conf. Series 916 (2017) 012043.
12. Jordan Lee, Lisa Roessler , Vibration Welded Composite Intake
Manifolds Design Considerations and Material Selection Criteria in
SAE technical paper series 970076.
13. Case Study On Plastic intake manifold in MATERIALS & DESIGN
13(6), 1992.
14. Ch. Indira Priyadarsini Flow analysis of intake manifold using CFD in
International Journal of Engineering and Advanced Research
Technology 2(1), 2016.
15. RepairPal Homepage http://repairpal.com/intake-manifold last
accessed on 2017/09/18.
16. Yu, J., Vuorinen, V., Kaario, O., Sarjovaara, T., & Larmi, M.:
Visualization and analysis of the characteristics of transitional under
expanded jets. International Journal of Heat and Fluid Flow 44,
140-154 (2013).

AUTHORS PROFILE

K. Sathishkumar is currently doing his Master of

Engineering in Engineering Design. His area of
research includes design, analysis, and manufacturing
methods. To his credit, he has published various
research papers in reputed journals and he is a
member in various professional bodies.

Dr. R. Soundararajan is currently working as an

Associate Professor in Department of Mechanical
Engineering. His area of research includes Design,
Manufacturing technology and Optimization. To his
credit, he has published various research papers in
reputed journals and filed various patent. He is a
member in various professional bodies.

G. Dinesh is currently doing his under graduation

in Department of Mechanical Engineering. His
research area includes Design and Manufacturing.

S. Surjith is currently doing his under graduation

in Department of Mechanical Engineering. His
research area includes Design and Analysis.

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