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Mukt Shabd Journal ISSN NO : 2347-3150

CFD Analysis of Four Engine Inlet Valve and Exhaust Valve Manifold System

Gopi Satyasai Kumar1 1 Research Scholar, Department of Mechanical Engineering, Godavari Institute of Engineering & Technology, Andhra Pradesh, India. M Bala Krishna2 2 Sr. Assistant Professor, Department of Mechanical Engineering, Godavari Institute of Engineering & Technology, Andhra Pradesh, India.

ABSTRACT: The design and manufacture of Internal Combustion (IC) Engines is under significant pressure for improvement. The next generation of engines needs to be compact, light, powerful, and flexible, yet produce less pollution and use less fuel. Innovative engine designs will be needed to meet these competing requirements. The time scales of the air flow, , liquid vaporization, turbulent mixing, species transport, chemistry, and pollutant formation all overlap, and need to be considered simultaneously. Computational (CFD) has emerged as a useful tool in understanding the fluid dynamics of IC Engines for design purposes.Fluid flow dynamics inside an engine combustion plays an important role for air-fuel mixture preparation. IC Engine model is developed using CATIAV5R20 tool. The model is then imported to Finite Element solver tool. ANSYS I.C Engine is used for post processing the results. Insight provided by CFD analysis helps guide the geometry design of parts, such as ports, valves, and ; as well as engine parameters like valve timing and fuel injection. Using CFD results, the flow phenomena can be visualized on 3D geometry and analysed numerically, providing tremendous insight into the complex interactions that occur inside the engine. This allows you to compare different designs and quantify the trade-offs such as soot v/s NOx, swirl v/s tumble and impact on turbulence production, combustion efficiency v/s pollutant formation, which helps determine optimal designs. In this paper the In cylinder cold flow CFD simulation of four stroke using hybrid approach of ANSYS fluent. The simulation is carried out using parameter and journal files which is symmetry geometry.The flow dynamics inside the cylinder for different minimum valve lift is studied using FEA. Dynamic motion is visualized and velocity magnitude is plotted for different angle from 0° to 720°. Finally velocities and crank angles for various valve lifts are compared.

KEYWORDS: Engine, inlet valve, Exhaust valve, Exhaust manifold, ANSYS fluent. condition needed for the fuel injection during the INTRODUCTION compression stroke. An internal combustion engine (ICE) is a heat CFD can be very well applied for analyzing any engine where the combustion of a fuel occurs with particular process. It can also be used for the an oxidizer (usually air) in a combustion modification of the existing engine design or can chamber that is an integral part of the working fluid also be employed for a new design of an engine. It is flow circuit. In an internal combustion engine the hoped that it may be benefitted in understanding the expansion of the high temperature and high-pressure application of CFD for fluid flow analysis of engine gases produced by combustion apply direct force to inlet and exhaust manifolds. some component of the engine. The force is applied The exception to this is the flows in the typically to , cylinder and valves. corners and small crevices of the combustion This force moves the component over a chamber where the close distance of the walls distance, transforming chemical energy into useful diminished out turbulence. Heat transfer, mechanical energy. In of these four evaporation, mixing and combustion rates all processes, the intake and compression stroke is one increase as engine speed increases. This increases of the most important processes which influences the time rate of fuel evaporation, the mixing of the the pattern of air flow structure coming inside fuel vapor and air as well as combustion process. As cylinder during intake stroke and generates the a result of the high velocity inside the internal combustion engine (ICE) , in cylinder flows are Volume IX, Issue VII, JULY/2020 Page No : 1269 Mukttypically Shabd turbulent Journal. In today’s world, major with maximum speed of 1500 ISSN rpm is NO taken : 2347-3150 for the objectives of engine designers are to achieve the analysis. The load and performance test is twin goals of best performance and lowest possible conducted. From the experiment back pressure and emission levels. To maximize the mass of air exhaust temperatures are measured. The mass flow inducted into the cylinder during the suction stroke, rate and velocities are calculated. Flow through the the intake manifold design, which plays an exhaust manifold is analyzed using commercially important role, has to be optimized. The design available software with mass flow rate and pressure becomes more complex in case of a multi cylinder as boundary conditions. engine as air has to be distributed equally in all the cylinders. Hence, configuration of manifold Vivekananda Navadagi and geometry becomes an important criterion for the SiddaveerSangamad [4] they analyzed the flow of engine design. from two different modified exhaust manifold with the help of Computational fluid LITERATURE REVIEW dynamics. To achieve the optimal geometry for the low back pressure they have analyzed two different PL. S. Muthaiah [1], He has analyzed the exhaust manifold, base geometry exhaust manifold exhaust manifold in order to reduce the backpressure and the modified geometry exhaust manifold. In the and also to increase the particulate matter filtration. base model of the exhaust manifold the outlet is at He has modified the different exhaust manifold by side of the first inlet where as in the modified model varying the size of the conical area of the exhaust of the exhaust manifold the outlet is at the centre of manifold and varying the size of the grid wire mesh the exhaust manifold. Analysis has been done for the packed throughout the exhaust manifold. When size two different exhaust manifolds. The results were of the grid mesh packed decreased the backpressure compared for the two models and it is found that the increases which leads to lower the performance of modified model gives low back pressure in the engine due to more fuel consumption and hence comparison with other base model which ensures the low volumetric efficiency. When size of the grid improvement in the efficiency of the engine. mesh packed increased the backpressure decreases The flow distribution in the exhaust the filtration of the particulate matter also reduces manifold channels would be highly dependent on the which will not satisfy the standards of the pollution header shape and the flow rate. Jafar M Hassan [5] control. Computational fluid dynamics is used for had analyzed the performance of the manifolds with the study of the exhaust manifold and best possible a tapered longitudinal section. The length of the design of the exhaust manifold with minimum manifold for this study was 127 cm while the backpressure and maximum particulate matter manifold diameter was 10.16 cm. Authors had used filtration efficiency is suggested. the numerical simulations (CFD) for this research work. The flow conditions corresponding to Re = K.S. Umesh, V.K. Pravin and K. 10x104, 15x104 and 20x104 were considered. The Rajagopal [2] In this work eight different models of results were analyzed in terms of uniformity exhaust manifold were designed and analyzed to coefficient. Based on their CFD simulation results, improve the fuel efficiency by lowering the they had concluded that the tapered header backpressure and also by changing the position of configuration provides better flow distribution as the outlet of the exhaust manifold and varying the compared to the header with circular cross-section. bend length. The eight different modified models are M.Usan[6] had applied a multi-disciplinary short bend centre exit (SBCE), short bend side exit optimization approach for the , (SBSE), long bend center exit (LBCE), long bend exhaust manifold and , in highly side exit (LBSE), short bend center exit with reducer integrated concurrent engineering software ( SBCER), short bend side exit with reducer framework. They had considered four-cylinder 1.4 (SBSER), long bend centre exit with reducer litre engine as a baseline model. The optimization (LBCER), long bend side exit with contained four major modules – Geometry, reducer(LBSER).After analysis they included that Structural, Cost and Fluid Dynamics – and the the exhaust manifold with long bend centre exit with relevant software for each module was applied. 1- reducer (LBCER), gives the highest overall dimensional transient CFD simulations were carried performance. out using AVL BOOST with the engine torque and catalytic converter inlet temperature over the engine Kulalet al.(2013) [3]work comprehensively rpm were being estimated. analyzes eight different models of exhaust manifold HessamedinNaemi[7] had employed and concluded the best possible design for least fuel numerical simulations (CFD methods) for estimating consumption. CFD is the current trend on the flow loss coefficient in manifolds. The flow inlet automotive field in reducing the cost effect for and exit was model using ‘mass-flow-inlet’ and analysis of various models on the basis of fluid flow. ‘pressure-outlet’ boundary conditions, with the A multi-cylinder Maruti - Suzuki Wagon-R engine Volume IX, Issue VII, JULY/2020 Page No : 1270 Muktconsideration Shabd Journal that the flow was compressible. The Internal combustion enginesISSN areNO quite : 2347-3150 different results from different turbulence models – standard from external combustion engines, such k-ε, standard k-ω, SpalartAllmaras model and RNG as steam or Stirling engines, in which the energy is k-ε model – were compared in terms of flow loss delivered to a working fluid not consisting of, mixed coefficient against the experimental data. Based on with, or contaminated by combustion products. their results, the authors had observed that the RNG Working fluids can be air, hot water, pressurized or k-ε turbulence model predictions were in close even liquid sodium, heated in a boiler. ICEs are usually agreement with the experimental data. powered by energy-dense fuels such as gasoline or The design of exhaust manifold for a 4- diesel, liquids derived from fossil fuels. While there are stroke high power medium –speed diesel engine was many stationary applications, most ICEs are used in carried out by Kyung-Sang Cho [8]. The typical mobile applications and are the dominant power supply operational range of the medium-speed diesel engine for vehicles such as , aircraft, and boats. was in the range of 700 – 1500 rpm and has power Typically an ICE is fed with fossil fuels outputs up to 6000 kW. The exhaust manifold will like natural gas or petroleum products such undergo thermal expansion due to high temperature as gasoline, diesel fuel or fuel oil. There's a growing of exhaust gas and also exposed to the vibration usage of renewable fuels like biodiesel for compression caused by the internal combustion engine. This was ignition engines and bi-ethanol for spark ignition studied using experimental methods by the authors. engines. Hydrogen is sometimes used, and can be made from either fossil fuels or renewable energy. Masahiro Kanazaki[9] had developed a multi-objective optimization method for the exhaust manifold by using STROKES IN DIESEL ENGINE: Air flows through Divided Range Multi-objective Genetic Algorithm. The the intake ports in the . On the intake stroke three-dimensional fluid dynamics inside the manifold the inlet valve opens just before the piston starts to travel was simulated using transient, Euler flow solver. The down the cylinder and air will then flow into the two objective functions for the optimization was i) cylinder. maximizing exhaust gas temperature at the end of exhaust pipe ii) maximize the charging efficiency. The authors were able to successfully optimize the manifold for both these objective functions and noted that the optimized model has high engine power than the baseline model.

I .A four stroke engine Fig 5. Suction Stroke An internal combustion engine (ICE) is a heat engine where the combustion of a fuel occurs with Compression Stroke an oxidizer (usually air) in a that is an integral part of the working fluid flow circuit. In On the compression stroke, the piston is travelling an internal combustion engine the expansion of the upwards and both intake and exhaust valves are closed. high-temperature and high-pressure gases produced by The air that is trapped in the cylinder is therefore combustion apply direct force to some component of compressed. Compressing the air raises its temperature the engine. The force is applied typically to a level where the fuel will ignite when it is injected to pistons, turbine blades, or a nozzle. This force moves into the cylinder. the component over a distance, transforming chemical energy into useful mechanical energy. The first commercially successful internal combustion engine was created by Etienne Lenoir around 1859 and the first modern internal combustion engine was created in 1864 by Siegfried Marcus. The term internal combustion engine usually refers to an engine in which combustion is intermittent, such as the more familiar stroke and two-stroke piston Fig 6. Compression Stroke engines, along with variants, such as the six- stroke piston engine and the Wankel . A Power Stroke second class of internal combustion engines use continuous combustion: gas turbines, jet engines and When the piston nears the top of its travel, fuel is most rocket engines, each of which are internal injected into the cylinder as a fine mist, as a result of the combustion engines on the same principle as previously very high pressure developed in the injector. The fuel described. Firearms are also a form of internal mixes with the hot air and ignites. This type of combustion engine. Volume IX, Issue VII, JULY/2020 Page No : 1271 Muktcombustion Shabd processJournal is the reason why the diesel engine upgrade your designing skillsISSN with NO the : 2347-3150 tremendous is also referred to as a “compression ignition engine”. improvement in this latest release.

The energy produced by combustion forces the piston CATIA V5, developed by Dassault Systems, down to produce the power. France is a completely re-engineered, Next-generation family of CAD//CAE software solutions for Product Lifecycle Management. Through its exceptionally easy-to-use and state-of-the-art user interface, CATIA V5 delivers innovative technologies for maximum productivity and creativity, from the inception concept to the final product. CATIA V5 reduces the learning curve, as it allows the flexibility of using feature-based and parametric designs.

CATIA offers a solution to shape design, styling, Fig 7. Power Stroke surfacing workflow and visualization to create, modify, and validate complex innovative shapes from industrial Exhaust Stroke design to Class-A surfacing with the ICEM surfacing Near the end of the power stroke, the exhaust valve technologies. CATIA supports multiple stages of product opens. The upward movement of the piston will force the sign whether started from scratch or from 2D sketches hot gas into the exhaust manifold. Near the top of the exhaust stroke, the exhaust valve closes and the inlet V. DESIGN AND ASSEMBLY valve opens in preparation for the cycle to be repeated. It takes two revolutions for the completion of the four stroke cycle, for each cylinder in the engine.

Fig. 5.1.VALVES OF ENGINE.

Fig 8. Exhaust Stroke

The purpose of the exhaust process is to remove the un- burnt and exhaust gases in the combustion chamber after the power stroke to the atmosphere through the exhaust manifold. Inlet process or suction process is the process of taking the fresh charge or air-fuel mixture or air into the combustion chamber. In this process inlet valve Fig.5.2. CYLINDER HEAD AND VALVE opens and the air from the atmosphere is sent into the ASSEMBLY combustion chamber. These two processes are very crucial in defining the performance of the engine.

IV.INTRODUCTION TO CATIA V5:

CATIA (Computer Aided Three Dimensional Interactive Application) as a new user of this software package, you will join hands with thousands of users of this high-end CAD/CAM/CAE tool worldwide. If you are already familiar with the previous releases, you can

Fig 5.3. CYLINDER HEAD ASSEMBLY Volume IX, Issue VII, JULY/2020 Page No : 1272 Mukt Shabd Journal ISSN NO : 2347-3150

Fig.5.7. Long Bend Side Exit with Reducer Fig.5.4. EXHAUST MANIFOLD WITH LONG BEND CENTRE EXIT

Fig 5.8.Short Bend Center Exit Fig.5.5. EXHAUST MANIFOLD WITH LONG BEND WITH REDUCER & CENTRE EXIT

Fig 5.9. Short Bend Center Exit with Reducer

Fig.5.6Long Bend Side Exit

Volume IX, Issue VII, JULY/2020 Page No : 1273 Mukt Shabd Journal ISSN NO : 2347-3150 Table 1. Boundary Conditions Of inlet valve and Exhaust valve

Boundary Mean Hydraulic Diameter

INLET 1 1 0.00877m

INLET 2 2 0.00877m

INLET 3 3 0.00877m

INLET 4 4 0.00877m Fig 5.10. Short Bend Side Exit Table 2. Boundary Conditions Of Exhaust Manifold

6.2. MESHING:

Fig 5.11.Short Bend Side Exit with Reducer

VI. BOUNDARY CONDITIONS AND MESHING In the finite element analysis the basic concept is to

analyze the structure, which is an assemblage of discrete pieces called elements, which are connected, Table 3. ICE Meshing report of an Engine together at a finite number of points called Nodes. Loading boundary conditions are then applied to these elements and nodes. A network of these elements is known as Mesh.

6.1.BOUNDARY CONDITIONS:

Type Zones Values Wall In valve1-stem, In valve 300 K (invalve1) 1-ob, Invalve 1-ch, Invalve 1-ib Wall Exvalve1-stem, 300 K (exvalve1) Exvalve 1-ob, Exvalve 1-ch, Fig.6.2.1. Meshing model of Inlet and Exhaust Valve Exvalve 1-ib Wall (in valve- Invalve 1- 300 K with Engine head port) port Wall Exvalve 1- 300 K (exvalve-port) port

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Fig.6.2.2.Meshing model of Exhaust Manifold with Fig 6.2.6.Meshing model of Exhaust Manifold with long bend Centre Exit long bend Side Exit

Fig 6.2.3. Meshing model of Exhaust Manifold with reducer with long bend Centre Exit Fig 6.2.7.Meshing model of Exhaust Manifold with long bend Side Exit With Reducer

Fig 6.2.4.Meshing model of Exhaust Manifold with short bend Centre Exit Fig 6.2.8.Meshing model of Exhaust Manifold with short bend Side Exit

Fig 6.2.5.Meshing model of Exhaust Manifold with Fig 6.2.9.Meshing model of Exhaust Manifold with short bend Centre Exit With Reducer Short bend Side Exit With Reducer Volume IX, Issue VII, JULY/2020 Page No : 1275 Mukt Shabd Journal ISSN NO : 2347-3150 VII. REAULTS AND GRAPHS 7.1. Inlet and Exhaust Valve with Cylinder Results:

Fig 7.1.4.Contours of velocity at Crank Angle 3680

Fig 7.1.1.Contours of velocity at Crank Angle 480

Fig 7.1.2.Contours of velocity at Crank Angle 1000 Fig 7.1.5.Contours of velocity at Crank Angle 6830

7.2.Exhaust Manifold results:

Fig 7.1.3.Contours of velocity at Crank Angle 1520 Fig 7.2.1: Pressure streamline of Exhaust Manifold

with long bend center exit

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Fig 7.2.2 : velocity streamline of Exhaust Manifold with long bend center exit Fig7.2.5: Pressure streamline of Exhaust Manifold with long bend side exit

Fig 7.2.3: Pressure streamline of Exhaust Manifold Fig7.2.6.: Velocity streamline of Exhaust Manifold with reducer long bend center exit with long bend side exit

Fig 7.2.4: Velocity streamline of Exhaust Manifold Fig7.2.7.: Pessure streamline of Exhaust Manifold with with reducer long bend centre exit reduer with long bend side exit

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Fig7.2.11: Pressure streamline of Exhaust Manifold Fig7.2.8:Velocity streamline of Exhaust Manifold with with reducer with short bend centre exit reducer with long bend side exit

Fig7.2.12: Velocity streamline of Exhaust Manifold

with reducer with short bend centre exit

Fig7.2.9: Pressure streamline of Exhaust Manifold with short bend centre exit

Fig7.2.13: Pressure streamline of Exhaust Manifold

with reducer with short bend centre exit

Fig7.2.10: Velocity streamline of Exhaust Manifold with short bend centre exit

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Fig7.2.14: Velocity streamline of Exhaust Manifold with reducer with short bend centre exit

Graph 1. Crank Angle V/S Swirl Ratio

Fig7.2.15: Pressure streamline of Exhaust Manifold with short bend centre exit

Graph 2. Crank angle V/S Tumble ratio

Fig7.2.16: Velocity streamline of Exhaust Manifold Graph 3. Crank angle V/S Mass-average Turbulent with short bend centre exit Kinetic Energy

Volume IX, Issue VII, JULY/2020 Page No : 1279 Mukt Shabd Journal ISSN NO : 2347-3150 VIII. CONCLUSION 1. Dynamic motion is visualized and velocity magnitude is plotted for different crank angle from 0° to 730°. 2. When the valve lifts increases velocity obtained decreases. 3. Exhaust stroke has the maximum influence on the air mixing and turbulence in the combustion chamber. 4. CFD/I.C Engine can be used as a useful tool to fix the parameters related to engine performance. 5. Forces exerted by gas particles in the manifold effect the values of back pressure and exit velocity, Graph 4. Crank angle V/S Volume-Average Cell due to which overall performance score on the Equivolume skew basis of these two parameters changes. 6. Short bend models show better performance, as 2KG 4KG 6KG 8KG 10KG 12KG compared with long bend models. 7. Due to increased length, differences in overall SBCE 940 976 1002 1036 1079 1111 performance score in long bend models are greater SBSE 1020 1071 1098 1113 1132 1172 than that of short bend models. And 8. Out of available set of alternatives, long bend LBCE 850 863 894 923 984 1012 centre exit (LBCE) model of manifold is the best one because it has scored rank first for overall LBSE 973 1005 1039 1076 1099 1125 performance score. SBCE 984 1012 1047 1077 1114 1154 R REFEERENCES [1]. PL. S. Muthaiah, “CFD Analysis of catalytic SBSER 1180 1214 1222 1222 1272 1303 converter to reduce particulate matter and SBSER 1037 1080 1112 1112 1187 1201 achieve limited back pressure in diesel engine”, Global induced during suction and compression LBSER 1138 1174 1219 1219 1276 1271 stroke l journal of researches in engineering A: Classification (FOR) 091304,091399, Vol.10 Table 3. Backpressure for Different Models in Issue 5 (Ver1.0) October 2010 Pascal at Exhaust Manifold [2]. K.S. Umesh, V.K. Pravin and K. Rajagopal

“CFD Analysis and Experimental Verification 2KG 4KG 6KG 8KG 10KG 12KG of Effect of Manifold Geometry on Volumetric SBCE 17.03 18.1 18.7 19.52 21.45 23.01 efficiency and Back Pressure for Multi-cylinder SI Engine” International Journal of Engineering SBSE 18.1 18.6 19.1 20.2 21.6 23.5 & Science Research IJESR/July 2013/ Vol- LBCE 20.2 21.33 22.07 23.52 23.98 24.77 3/Issue-7/342. [3]. Kulal et al.(2013) “Experimental Analysis of LBSE 18.71 18.92 19.23 20.12 22.21 23.65 Optimal Geometry for Exhaust Manifold of Multi-cylinder SI Engine for Optimum SBCER 17.7 17.79 18.23 19.86 21.1 23.89 Performance” Global journal of researches in SBSER 16.8 17.12 18.6 19.9 21.76 23.92 engineering A: Classification (FOR) 091304,091399, Vol.10 SBSER 17.3 18.67 19.54 21.96 23.65 24.71 Issue 5 (Ver1.0) October 2010. LBSER 17.9 18.01 19.1 20.65 21.86 23.98 [4]. Vivekananda Navadagi and SiddaveerSangamad Development of a Partial Filter Table 4. Exhaust Velocity for Different Models in Technology for Hdd Retrofit, Sae Technical Meter per Second (m/s) in Exhaust Manifold Paper 200601-0213.Jacobs, T., Chatterjee, S., Conway, R., Walker, Development of a Partial Filter Technology for Hdd Retrofit, Sae Technical Paper 2006-01-0213. Volume IX, Issue VII, JULY/2020 Page No : 1280 Mukt Shabd Journal ISSN NO : 2347-3150 [5]Jafar M Hasan, Wahid S Mohammad, Thamer A Considering Fatigue Strength due to Vibration”, Mohamed, Wissam H Alawee, “CFD Simulation Journal of the Korean Society of Marine for Manifold with Tapered Longitudinal Section” Engineering, vol-37, No.7, 2013; International Journal of Emerging Technology and Advanced Engineering, Volume 4, Issue 2, [9]Masahiro Kanazaki, Masashi Morikawa, Shigeru February 2014 Obayashi and Kazuhiro Nakahashi, “Exhaust Manifold Design for a Engine Based on Engine [6]M. Usan, O. de Weck, D. Whitney, “Exhaust System Cycle Simulation” International Conference Parallel Manifold Development Enhancement through Computational Fluid Dynamics, Japan, May 2002; Multi- [10]Hong Han-Chi, Huang Hong-Wu, Bai Yi-Jie, Attribute System Design Optimization”, American “Optimization of Intake and Exhaust System for Institute of Aeronautics and Astronautics; FSAE Car Based on Orthogonal Array Testing” [7]HessamedinNaeimi, DavoodDomiryGanji, International Journal of Engineering and MofidGorjivadirad and MojtabaKeshavarz, “A Technology, Volume 2, No. 3, March 2012; Parametric Design of Compact Exhaust Manifold [11]Xueyuan Zhang, Yu Luo, Jianhua Wang, “Coupled Junction in Heavy Duty Diesel Engine Using Thermo-Fluid-Solid Analysis of Engine Exhaust Computational Fluid Dynamics Codes” Thermal Manifold Considering Welding Residual Stresses” Science, Volume-15, No. 4, 2011; Transactions of JWRI, 2011L; [8]Kyuang-Sang Cho, Kyung-Bin Son, Ue-Kan Kim, “Design of Exhaust Manifold for Pulse Converters

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