International Journal of Advance Engineering and Research Development

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1 Scientific Journal of Impact Factor(SJIF): International Journal of Advance Engineering and Research Development Volume 2,Issue 5, May e-issn(o): p-issn(p): Design Analysis and Weight Reduction of Car Flywheel using Finite Element Analysis Palak J Patel 1, Arvind S. Sorathiya 2 1 PG Scholar, Mechanical Engg. Department, Govt. Engg. College, Bhuj , India 2 Associate Professor, Mechanical Engg. Department, Govt. Engg. College, Bhuj , India, Flywheel is a rotating mechanical device that is used to store rotational energy. Flywheels have a significant moment of inertia and thus resist change in rotational speed. Flywheel development has been dominated by mobile application where minimizing mass is critical. The main problem with flywheel is its higher weight which results in lower rotational speed. Flywheel is designed using 3 dimensional modelling software. Then the 3-D model was imported into ANSYS using the IGES format. Using finite element analysis, static structural analysis carried out by considered three different materials namely Gray cast iron, 5059 H321 aluminium alloy and Kevlar carbon fiber and their relative performance have been observed respectively. The finite element idealization of this model was then produced using the tetrahedron solid element. The analysis was performed in a static condition. We find out the total deformation, normal stress and equivalent stress by using FEA software. In this paper by observing the results of static analysis obtained carbon fiber is suggested as better material for designing of wheel as it has lower weight. KEYWORDS: - Flywheel, 3-dimensional model; Finite element analysis; Static structural analysis. I. INTRODUCTION Flywheels serve as a kinetic energy storage and retrieval device that stores twisting or spinning motion and then release it as rotational kinetic energy to provide motion when the requirement of the energy is more than supply. The amount of energy stored in a flywheel is proportional to square of its rotational speed. The main function of flywheel is to smoothen out variation in the speed of a shaft caused by torque fluctuation [7]. Flywheels are typically made of steel and rotate on conventional bearings having a higher weight. These are generally limited to a revolution rate of a few thousand RPM. As it is necessary to modify or design advanced flywheel having a lighter weight and less fracture possibilities with composite material. For that stress analysis are carried out to flywheel for different composite materials [8]. II. TYPES OF WHEEL The geometry of a flywheel may be as simple as a cylindrical disc of solid material, or may be of spoke construction like conventional wheels with a hub and rim connected by spokes or arms Small fly wheels are solid discs of hollow circular cross section. As the energy requirements and size of the flywheel increases the geometry changes to disc of c entral hub and peripheral rim connected by webs and to hollow wheels with multiple arms. [9] I. Fig 1 Types of flywheel [9] III. LITERATUTRE All rights Reserved 1550

2 Mofid Mahdi et al. (2011) [1] worked on three solid flywheel disk profiles that are constructed using functions of cubic splines. Using FEM, the cubic splines parameters are analysed systematically to seek a maximum stored kinetic energy per unite mass. All FEM computations were carried out using ANSYS. Three flywheels thickness profiles were analysed based on cubic splines functions. The study concluded that thinner flywheel disk has a higher capability of kinetic energy storing the corresponding maximum effective stresses are found near the centre of flywheels where thickness should be maximum. Mauleeswaran Senthil Kumar et al. (2012) [2] had put forward discussion of composite flywheel design. Based on analytical approach for calculating stresses in flywheel using genetic algorithm. The problem was solved for a sample flywheel with varying materials. Minimum mass required is found out for different value of energy storage and corresponding other parameters are found out for five different materials cast iron, aluminium alloy, marging steel, carbon fiber composite and E Glass fiber epoxy. Finally, from the analysis, it is clear that, among five materials carbon fibre composites have lowest mass kg and highest angular velocity 354 rad/sec for 500 j energy storage. It can be also used in high speed applications, as the values of angular velocities obtained are higher than that of other materials. Sushama G Bawane et al. (2012) [3] had proposed flywheel design, and analysis the material selection process. The Gray cast iron, ASTM 30.SAE 111 was selected for the flywheel of MARUTI SUZUKI OMNI. The FEA model is described by using CATIA software to achieve a better understanding of the mesh type, mesh size and boundary conditions applied to complete an effective FEA model. Gray cast iron model was compared with aluminium alloy. After analysis the total deformation of Gray cast iron including equivalent stress Mpa, Normal stress Mpa and shear stress Mpa was mm while in aluminium alloy the total deformation was mm. Hence Gray cast iron can be used to reduce stress and weight of flywheel. Akshay P. Punde, et al. (2013) [4] has presented the investigation of a flywheel, A flywheel model is prepared by CATIA software, and analyzed by using Finite Element Analysis method. Further it is used to calculate the Stresses inside the flywheel by ANSYS; finally the comparison study between the Design and analysis with existing flyw heel is carried out. The total deformation in Gray cast iron is x 10 ³ while in S Glass epoxy total deformation is 5,3399 x 10 ³. Hence s glass epoxy can be used in flywheel to store higher energy with less mass. Lavakumar et al. (2013) [5]gives the design and optimize the flywheel for the best material. The flywheel is modelled with solid 95 (3-D element), the modelled analyses using free mesh.von-misses stress for both materials (mild steel and mild steel alloy) is compared. The flywheel is modelled with solid elements. To reduce stress and deflection flywheel 40% titanium element is added as alloying element to the mild steel. The maximum deflection of mild steel alloy is 0.444E-05 meters which is less than maximum deflection of mild steel which is found to be 0.369E-03 meters. Thus mild steel alloy is best, from rigidity point of view. Maximum von-misses stress in flywheel is N/m² for mild steel alloy which is less than the maximum von-misses stress of flywheel which is found to be N/m². Hence design is much safe based on strength point of view for mild steel alloy than for mild steel. Kishor D. Farde et al. (2014) [6]reducesthe weight of automobile by using composite material. In this research Work taking Flywheel as an Automobile component and applying FEA analysis using ANSYS to optimize weight and strength of flywheel. Here Performing Analysis on metal flywheel, carbon fibre flywheel and composite i.e. metal and carbon fibre flywheel. By using ANSYS stresses obtained & compared with analytical calculations, also weight is compared. A composite material allows a higher rotational speed and this result in flywheel rotors with hig h specific energy and light in weight. Composite materials are therefore a better choice than metals when designing flywheel rotors. The theoretical specific energy of composite rotors is around five times higher than metallic ones. Composite materials als o have safety advantage over metallic material. IV. MODELING OF WHEEL Creo is software which is used for creation and modifications of the objects. In Creo design and modeling feature is available. Design means the process of creating a new object or modifying the existing one. Drafting means the representation or idea of the object. Modeling means create and converting 2D to 3D. By using Creo software, c reate the model of the Flywheel. Step Involved In Design 1. Draw the profile diagram of the Flywheel. 2. Now revolve the profile body about respect to axis. 3. By selecting the face of rim, the required design is drawn on the surface and teeth are obtained by pattern All rights Reserved 1551

3 Fig 1Flywheel Model of Maruti Suzuki swift Fig.2 Flywheel Model in Creo V. FINITE ELEMENT ANALYS IS The Finite Element Technique produces many simultaneous algebraic equations, which are generated and solved on a digital computer. The Finite Element Method originated as a method of stress analysis. The Finite Element Method is firmly established as a powerful and popular analysis tool. It is a numerical procedure for analyzing structures and continua. Finite element procedures are used in design of buildings, electric motors, heat engines, ships, airfra mes and space crafts. The Finite Element Method, in general, models a structure as an assemblage of s mall elements. FEA has become a solution to the task of predicting failure due to unknown stresses by showing problem areas in a material and allowing designers to see all of the theoretical stresses within. This method of product design and testing is far superior to the manufacturing costs, which would accrue if each sample was actually built and tested. FEA consists of a computer model of a material or design that is stressed and analyzed for specific results. It is used in new product design, and existing product refinement. In case of structural failure, FEA may be used to help determine the design modifications to meet the new condition. FEA uses a co mplex system of points called nodes, which make a grid called a mesh. This mesh is programmed to contain the material and structural properties, which define how the structure will react to certain loading conditions. A. Mesh Generation The mesh was meshed with tetrahedron structural solid elements. The wheel was meshed using an element edge length is 2mm. The total number of nodes and elements are and respectively. The finite element realization of the wheel obtained is shown in fig.3. B. Material Properties Fig.3 Meshing of All rights Reserved 1552

4 Static structural analysis of flywheel using Finite element analysis is carried out to analyse zones with higher stress concentration. For analysis, three materials are selected Gray cast iron, 5059 H321 aluminium alloy and Kevlar carbon fiber and to show their relative performance using finite element analysis. This materials properties are shown in table 2. Table I. Material Properties Properties Gray cast iron 5059 H321 Al alloy (11) Fiber (9) Kevlar Carbon Density (g/cm 3 ) Ultimate Tensile Strength (MPa) Poisson s ratio Young's Modulus (Gpa) C. Static Structural Analysis Import developed Creo model into Ansys Select the type of analysis require. Applying the material Create the mesh for the imported model Fixing the geometry Apply the loads and angular velocity Run the analysis 1. Gray cast iron Results Equivalent stress Total deformation Fig.4 Equivalent stress in gray cast All rights Reserved 1553

5 Normal stress Fig 5 Total deformation in gray cast iron H321 AlAlloy Results Equivalent stress Fig 6 Normal stress in gray cast All rights Reserved 1554

6 Fig.7 Equivalent stress in 5059 H321 Al alloy Total deformation Normal stress Fig.8 Total deformation in 5059 H321 Al All rights Reserved 1555

7 Fig. 9 Normal stress in 5059 H321 Al alloy 3. Kevlar carbon fiber Equivalent stress Total deformation Fig. 10 Equivalent stress in Kevlar carbon All rights Reserved 1556

8 Fig. 11 Total deformation in Kevlar carbon fiber Normal stress Fig. 12 Normal stress in Kevlar carbon All rights Reserved 1557

9 D. Result Comparison Table II.Results Comparison Material Total Deformation(mm) Equivalent Stress (MPa) Normal Stress (MPa) Mass (Kg) Max. Min. Max. Min. Max. Min. Gray cast iron H321 Al Alloy Kevlar Carbon Fiber In table II result of static structural analysis is given. After completion of meshing we apply fixed support at rim. For gray cast iron and 5059 H321 Al Alloy, The total deformation of flywheel maximum is mm at hub portion and minimum 0 mm at rim of flywheel. The equivalent stress is Mpa and MPa. The normal stress maximum is MPa and minimum is MPa. For 5059 Al alloy, the total deformation of flywheel maximum is mm at hub portion. The equivalent stress is Mpa and MPa.The norma l stress maximum is MPa and minimum is MPa. For Kevlar carbon fiber, the total deformation of wheel maximum is mm and minimum is 0 at hub portion. The equivalent stress is Mpa and MPa. The normal stress maximum is Mpa and minimum is MPa. For three of materials, total deformation maximum at shaft hole and minimum at rim and equivalent stress maximum at the centre of the flywheel and minimum at rim. VI. CONCLUS IONS Model of the flywheel is generated in Cre-o and this is imported to ANSYS for processing work. An angular velocity 471 rad/sec is applied in the direction of the rotation of flywheel made of gray cast iron, 5059 H321 Al Alloy & kevlar Carbon Fiber and rim of the flywheel is fixed. Following are the conclusions from the results obtained: 1. Gray cast iron flywheel is subjected to more total deformation compared to 5059 Al alloy and carbon fiber. 2. Gray cast iron wheel is subjected more von-misses stress and normal stress compared to 5059 H321 Al alloy and carbon fiber. 3. Weight of kevlar carbon fiber is 80 % less compared to gray cast iron and 5059 H321 Al alloy. 4. Kevlar carbon fiber has no erosion and corrosion problems. 5. By comparing all result we are suggested that kevlar carbon fiber is better material than gray cast iron and 5059 H321 Al alloy for designing of wheel. REFERENCES [1] Mofid Mahdi An optimal two dimensional geometry of flywheel for kinetic energy storage international journal of thermal and environmental engineering (IJTEE) - vol 3 issue , page no [2] Mauleeswaran senthil kumar, yogesh kumar optimization of flywheel material using genetic algorithm [3] Sushama G Bawane, A P Ninawe and S K Choudhary, Analysis and optimization of flywheel, Intern ational Journal of mechanical engineering and robotics Vol. 1, No. 2, July [4] Akshay P. Punde, G.K.Gattani, Analysis of Flywheel, International Journal of Modern Engineering Research (IJMER), Vol.3, Issue.2, March-April pp [5] Lavakumar, R.prasanna Srinivasan, Design and analysis of light weight motor vehicle flywheel, International Journal of Computer Trends and Technology (IJCTT) volume 4 Issue -7July [6] Kishor D Farde, Dr Dh iraj S Deshmu kh [2014] composite flywheel for h igh speed application IJIRA E ISSN vol 1 issue 6 (July 2014). [7] Sudipta Saha, Abhik Bose, G. Sai Tejesh, S.P. Srikanth, Computer aided design & analysis on flywheel for greater efficiency International Journal of Advanced Engineering Research and Studies, IJAERS/ Vol. I/ Issue II/January- March, 2012/p [8] Breakthrough in Ricardo Kinergy second generation high- speed flywheel technology, press release date 22 august All rights Reserved 1558

10 [9] Machine design ІІ, Prof K. Gopinath and M.M Mayuram. [10] [11] [12] [13]Text book of Finite Element Analysis by P.Shesu. [14] [15] [16] Jigar car pvt. Ltd. Himmatnagar. [17] Devine metallurgical services and pvt. Ltd. All rights Reserved 1559