Analysis and Optimization of Material for Bajaj Platina Motorcycle Alloy Wheels

Transcription

1 Analysis and Optimization of Material for Bajaj Platina Motorcycle Alloy Wheels J. Kiran Putra, K. Arjun Kumar, A. Adish Krishna Department of Automobile Engineering Rajalakshmi Engineering College, Chennai, India Abstract The on board safety of a rider and pillion on a motorcycle has equal importance in both its design aspect as well as for its successful commercial sale. In this paper, the 3D model for both the front and rear alloy wheels of Bajaj Platina Motorcycle with its original alloy material Al T61 was modelledandanalysed to assess the deformation and stresses induced in it at various static and dynamic load conditions. It is done using a commercial Finite element analysis software package. Furthermore, the alloy material for the same wheels (with unchanged design) was changed to Alumina alloy and same analysis procedures were carried out for estimating the performance of the selected alloy material as a suitable replacement for the existing alloy. The analysis results show that the chosen substitute material has better performance in comparison to the current alloy material used in the wheel with lower deformation rate and stress values. Keywords - Material optimisation; Two wheelers; Finite element analysis; Alloy wheels I. INTRODUCTION An automobile wheel s primary function is to withstand the weight of the vehicle, the stresses generated such as transmission torque and braking torque.it must also be strong enough to provide a cushioning effect, should be well balanced and must be as light as possible for better riding comfort as well as vehicle efficiency. The maximum road loads and shocks are taken up by the rims and ribs of the allow wheels due to uneven surface of the road. Figure 1 shows the chosen alloy wheel of the Bajaj Platina motorbike. Due to the deformation, the alloy wheels might experience a failure to hold in the gas pressure within the tyre and can lead to vibrations while riding. Therefore, choosing the right alloy wheel material, its optimisation and understanding its reaction to various impact loads ensures optimum performance, durability and safety to the motorist. Over the years, engineering problems have beensolved using many computer software based approach and its results were found to be close to the true value. Hence, software based FEA approach was adopted in this study to carry out the design analysis and material optimisation. Pavan. P Department of Automobile Engineering Rajalakshmi Engineering College, Chennai, India II. MATERIALS AND METHODOLOGY Material selection process is one of the notable methods of effective engineering design as it determines the reliability of the design in terms of industrial as well as economical aspects. So, selection of material plays a key role in determining the functional efficiency of the final product. In this summary, we have adopted alumina alloy as an alternative for the existing design. A. Alumina Alumina, commonly termed as Aluminum Oxide is synthetically processed from Aluminum Oxide.Alumina has good thermal conductivityproperties.metallic Aluminium is highly reactive with atmospheric oxygen and is also wear resistant.it exhibits higher stiffness and strength.it is available at a purity range from 94%. B.Analysis Methodology The alloy wheels were analysed under two different loading conditions i.e., wet weight and wet weight with two people (65Kgseach). C. Static Condition ( Wet Weight ) The reaction force acting on the front wheel is much lesser than the reaction force acting on the rear wheel because of the proximity of the centre of gravity to the rear wheel. Table I. contains the various loads for this condition. D. Dynamic Condition ( Wet Weight ) There are basically two types of dynamic conditions which are acceleration and braking. During acceleration, there is a shift of weight towards the rear end of the vehicle and thus the rear wheel. Similarly, during braking there is a shift of weight to the front wheel of the vehicle. E. Static and Dynamic Condition (Wet weight with two people (65Kgs each)) The above explained concept remains the same; however the reaction force experienced by each wheel would be significantly higher than the ISSN: Page 16

2 previously explained conditions. Table II. contains the various loads on the wheel with two people. TABLE I.LOAD ON WHEEL WITH NO RIDER ( WET WEIGHT ) Conditions Stationary Acceleration Deceleration (Braking) Wheels Load (N) Pressure (MPa) Front Rear Front Rear Front Rear TABLE II.LOAD ON WHEEL WITH TWO PEOPLE ( WET WEIGHT + AVERAGE WEIGHT OF TWO PEOPLE ) Conditions Stationary Acceleration Deceleration (Braking) Wheels Load (N) Pressure (MPa) Front Rear Front Rear Front Rear III. PHYSICAL AND CHEMICAL PROPERTIES A 3-D model was created using CATIA software after noting downall the required dimensions from the wheel under study. A small portion of the wheel was cut from the outer section using a cutting tool. The wheel sample was then tested at an industry certified materials testing laboratory for metallurgical analysis and the following results were obtained as shown in Table III. material chosen in this project is Alumina and itscorrespondingphysical properties are noted and a comparison of the same is tabulated. The physical properties required to define a new material in ANSYS material library is given below in Table IV. TABLE IV.COMPARISON OF PHYSICAL PROPERTIES OF THE TWO ALLOYS S.No. Properties Al356.0-T61 Alumina 1. Density (Kg/m 3 ) Young s Modulus (GPa) Poisson Ratio Bulk Modulus (GPa) Shear Modulus (GPa) Tensile Yield Strength (MPa) 7. Tensile Ultimate Strength (MPa) IV. MODELLING AND MESHING The analysis procedure of alloy wheelrequiresa 3- D model that is further imported in ANSYS Workbench for meshing and analysis purposes. A. Catia 3D Model TABLE III.CHEMICAL COMPOSITION OF AL356.0 T61 Elements Wt (%) Elements Wt (%) Fe Si Mn <0.01 Cu Ni <0.01 Cr <0.001 Ti Sn <0.002 V Co Zn Pb Mn Al The physical properties of Al356.0-T61 are needed to perform the analysis on the wheel. The alternative Fig 1 : Alloy wheel 3D Model A 3-D model of the alloy wheel is created in CATIA Software using the measured dimension from the bike. This Model file is then exported to the ANSYS Workbench and analysis is carried out considering different load conditions. B. Meshing Analysis In the ANSYS WORKBENCH, the 3-D model of alloy wheel is finely meshed. The quality of meshing adopted is fine mesh and the structure used to mesh is tetrahedral of unit 2. The mesh is checked for critical area based on which the final meshing of alloy wheel is completed. The Final product of fine meshing of alloy wheel is shown in the Fig. 2 ISSN: Page 17

3 Fig 2 : Fine Meshed Alloy Wheel Mesh details: Global Mesh 1. Element size : 5mm Patch Conforming Method 2. Mesh quality : Fine 3. Aspect ratio : min 1.1 max Jacobian ratio : min -100 max Skewness : min 2.99 max Aspect factor : min 0 max 0 7. Transition Ratio : Relevance : 100 V. RESULTS AND DISCUSSIONS The Imported 3-D model ofplatina Bike alloy wheel was defined with two different materials like Al356.0-T61 and Alumina. They were then analysed under different load conditions and the results in terms of von-misses stress, displacement were obtained from the ANSYS workbench. Now theanalyses with corresponding pictures of ANSYS from both materials comparing the results are shown below. A. Static Condition Front wheels with kerb weight alone Under static wet weight condition, the structural analysis was performed on the alloy. From figure 3 and figure 3, the maximum deformation for A356.0T-61 was found to be mm and the maximum deformation for Alumina was found to be mm both occurs at the point of loading. Fig 3 : Total Deformation stresses on Al356.0-T61 Similarly, the maximum equivalent (Von-Mises) stress for A356.0T-61 and Alumina Alloy was found to be the same at MPaand, which was found to be considerably lower in comparison to the tensile yield and ultimate strength. Fig 4 : Equivalent Von Mises Stress Al356.0-T61 ISSN: Page 18

4 B. Static Condition Rear wheel with two people on board Under static condition with two people on board, (Maximum load of 130kgs), the structural analysis was performed on the alloy. From figure 5 and figure 5, the maximum deformation for A356.0T- 61 was found to be mm and the maximum deformation for Alumina was found to be mm both occurs at the point of loading. Fig 6 : Equivalent Von Mises Stress Al356.0-T61 C. Dynamic Condition Acceleration Front wheel with kerb weight alone Fig 5 : Total Deformation stresses on Al356.0-T61 Under dynamic acceleration condition, considering just the kerb weight of the vehicle,thestructural analysis was performed on the alloy. From figure 7 and figure 7, the maximum deformation for A356.0T-61 was found to be mm and the maximum deformation for Alumina was found to be mm both occurs at the point of loading. Similarly, the maximum equivalent (Von- Mises)stress for A356.0T-61 and Alumina Alloy was found to be the same at MPaand, which was found to be considerably lower in comparison to the tensile yield and ultimate strength. ISSN: Page 19

5 D. Dynamic Condition Braking Rear wheel with a maximum load of 130kgs Under dynamic acceleration condition, considering just the kerb weight of the vehicle,thestructural analysis was performed on the alloy. From figure 9 and figure 9, the maximum deformation for A356.0T-61 was found to be mm and the maximum deformation for Alumina was found to be mm both occurs at the point of loading. Fig 7 : Total Deformation stresses on Al356.0-T61 Similarly, the maximum equivalent (Von-Mises) stress for A356.0T-61 and Alumina Alloy was found to be the same at MPa and, which was found to be considerably lower in comparison to the tensile yield and ultimate strength. Fig 9 : Total Deformation stresses on Al356.0-T61 Fig 8 : Equivalent Von Mises Stress Al356.0-T61 Similarly, the maximum equivalent (Von-Mises) stress for A356.0T-61 and Alumina Alloy was found to be the same at MPa and, which was found to be considerably lower in comparison to the tensile yield and ultimate strength ISSN: Page 20

6 Acknowledgment This research was supported by Rajalakshmi Institutions. We thank our staff from Rajalakshmi Engineering College who provided insights and expertise that greatly assisted the research. References Fig 10 : Equivalent Von Mises Stress Al356.0-T61 [1] Vamsi Krishna Mamidi., 2013., " Design Analysis of Two Wheeler Lighter Alloy wheel "., International Journal of Engineering, Vol6, N0.15, November [2] Vikrant Deepak., 2012., " Modelling and Analysis of Alloy Wheel of Four Wheeler Vehicle "., International Journal of Mechanical Engineering and Robotics Research, Vol. 5, No.1, October [3] Sourav Das., 2014., " Design and Weight Optimization of Aluminium Alloy Wheel"., International Journal of Scientific and Research Publications., Vol. 4, No.6, June [4] Priya Udasi, Sanjay Khumbare., 2012., "Design and Analysis of Two Wheeler Wheel with replacement of Aluminium Alloy"., International Journal of Recent Technology and Engineering.,Vol.3,No.4, September [5] C. Bosl, G.L Gergani, R. Tovo., " Fatigue Properties of a Cast Aluminium Alloy for Rims of Car Wheels"., Materials Science and Metallurgy( 2008). [6] "Automobile Engineering "., vol.1., by Dr. Kirpal Singh. [7] " Automobile Mechanics " by Dr. N.K Giri [8] "Engineering Materials and Metallurgy" by Dr. V. Jayakumar. [9] Riesner, M. and DeVries, R., "Finite Element Analysis and Structural Optimization of Vehicle Wheels," SAE Technical Paper , 1983, doi: / [10] Courval, G., Chamberlain, B., and Pattemore, D., "Effects of Alloy Composition and Condition on Filiform Corrosion Performance of Cast Aluminum Wheels," SAE Technical Paper , 1997, doi: / VI. CONCLUSION On performing Static Structural and Transient structural analysis on both the existing Al356.0-T61 and the proposed new Alumina alloy without any modification in the model design, the amount of deformation and the equivalent von-mises stress was found to be lesser in Alumina alloy than Al356.0-T61 at the point of loading. The maximum equivalent von-mises stress experienced by both the existing alloy and the proposed alloy is much lesser than the tensile yield strength and Tensile ultimate strength; therefore the stress experienced is safe. Hence the proposed new alloy material i.e., Alumina, has better working conditions and can be a suitable replacement to the existing alloy i.e., Al356.0-T61 for the Baja Platina Motorcycle alloy wheels. ISSN: Page 21