IDL - International Digital Library Of Technology & Research Volume 1, Issue 5, May 2017
Available at: www.dbpublications.org
International e-Journal For Technology And Research-2017
Numerical Simulation of Knuckle Joint Using Finite Element Method: A New Approach Based on Composite VIVEK SHAW 1, TANUJ SRIVASTAVA2,ROHIT GHOSH3, DR. RABINDRA NATH BARMAN 4 Department of Mechanical Engineering 1, 3
B.Tech Student, National Institute of Technology, Durgapur; West Bengal, 713209, India
2
M. Tech Student, National Institute of Technology, Durgapur; West Bengal, 713209, India
4
Assistant Professor, National Institute of Technology, Durgapur; West Bengal, 713209, India
Abstract:For
the past few decades, there has been a rapidprogress in the field ofmaterial science which has resulted in the reduction of cost and weight of materials. This modified systems developed by incorporating various advanced and smarter materialshas led to areduction in number of accidents andtherefore, the safety has increased, which again has been an utmost concern for any industry in modern times. The present work is an attempt to provide the readers with a comparative overview in the context of conventional and advanced materials focusing on a mechanical joint, i.e. the Knuckle joint. A Knuckle joint finds its extensive application for connecting two rods subjected to normal tensile load and requiring flexibility in its angular movements. Here, we are suggesting a modification over theconventionally used material, such as Aluminium alloythat is widely used for manufacturing the Knuckle joints.The results obtained from our study approves that the use of composite material not only decreases the weight of the material but it also improves the life of the component as the composite material shows less deformation in comparison to the conventional one. In the present work, CATIA V5R18 has been used for modellingthe 3D geometry of Knuckle Joint and ANSYS (Workbench 16.2) is been used for
IDL - International Digital Library
finite element analysis of the same with the conventional and composites materials respectively. Composite analysis is based on Rule of mixtures. Keywords:Knuckle Joint, CATIA V5R18, ANSYS 16.2, FEM, Carbon FiberAluminum. 1.
INTRODUCTION
Knuckle Joint is a mechanical part which is used to connect two rods under tensile load when there is a requirement of asmall amount of flexibility, or angular moment is necessary. The line of action of theload is always axial or linear [1]. The axes of these two rods either coincide or intersect and lie in one plane. A knuckle joint is unsuitable to connect two rotating shafts, which transmit torque [2]. Knuckle Joint is named so because it is free to rotate about the axis of a knuckle pin.A typical knuckle joint has the following parts namely [3]. 1) Fork end 2) Eye end 3) Knuckle pin 4) Collar 5) Taper pin
1|P a g e
Copyright@IDL-2017
IDL - International Digital Library Of Technology & Research Volume 1, Issue 5, May 2017
Available at: www.dbpublications.org
International e-Journal For Technology And Research-2017 Fork end, eye end, and collar are provided with coaxial holes. Knuckle pin hold the fork end and the eye end together in a position. The knuckle pin is held in its position with the help of a collar and a taper pin. These joint are used for different types of connections, e.g. tie rods, tension links in thebridge structure [4]. A Knuckle joint can easily be disengaged when required. Knuckle Joint is designed and used in different type of equipment for transmitting load. Some researchers have worked on the optimization of steering knuckle which targets on the reduction of weight as the objective function without compromising in terms of strength, frequency, and stiffness. The Knuckle worked on undergoes varying load under different condition but it was modeled such that it does not affect the steering performance of the vehicle. The work was done in HyperWorks and solved in RADIOSS solver [5][6]. Purushottam Dumbre et al.[7] performed their study with the aim to reduce the weight of knuckle joint and performed finite element analysis using OptiStruct (Hyper works). As weight also becomes an important aspect in the field of racing industry as it affects the transmission efficiency of the device. Knuckle Joints used for steering in racing cars are also analyzed and optimized in accordance with the weight. Nishant Vibhav Sexena et al. [8] performed the study and analysis on Knuckle Joint with the replacement of the actual material. They worked on the maximisation of safety, making the system simple and eco-friendly. It was seen that the production of the Joint become economical but the strength got reduced to some extent. Another study shows a model which has been drawn in CATIA [9] Koszalkaet et al. [10] used FEM for the frame analysis of a low loader truck. In this study composite material is applied using rule of mixture. Similar kind of study using has been done by Rohit Ghosh et al.[11]. The performed their study on leaf spring model where carbon fibre steel composite is applied on 8th and 9th laminated plate. 2.
ANALYTICAL CALCULATION
IDL - International Digital Library
Dimensions of the Knuckle Joint is shown in Table 1. Table 1: Shows the dimensions of different parts of Knuckle Joint Part Diameter of rod (d) Diameter of pin (d1) Outer Diameter of eye (d2) Diameter of Knuckle pin head and collar (d) Thickness of Single eye or rod end (t) Thickness of Fork (t1) Thickness of Pin head (t2)
Dimension 36 mm 36 mm 72 mm 54 mm 45 mm 27 mm 18 mm
The axial load applied P = 70000 N We know, the allowable stress for the rod material [2]. Ďƒt = (Ultimate tensile stress/ Factor of safety) = 280/2 = 140 Mpa We know, the allowable shear stress for the rod material [2]. Ď„= (shear strength/ Factor of safety) = (207/2) = 103.5 Mpa Failure of solid rod in tension [2] Ď€ đ?‘ƒ = ∗ đ?‘‘2 ∗ Ďƒđ?‘Ą 4 Ďƒt = 68.77 Mpa Failure of eye end in tension [2] đ?‘ƒ = đ?‘‘2 − đ?‘‘1 ∗ đ?‘Ą ∗ Ďƒđ?‘Ą Ďƒt = 43.2 Mpa Properties of carbon fibre with aluminium is found by rule of mixing. Young’s modulus Ec=EmVm+EfVf Ec= 0.4*69000+0.6*300000=207600 Mpa Density Ď c=Ď mVm+Ď fVf Ď c= 0.4 *2700+0.6*1800= 2160 kg/m3 Poisson’s ratio Âľc=ÂľmVm+ÂľfVf Âľc= 0.4*0.334+0.6*0.28= 0.3016
2|P a g e
Copyright@IDL-2017
IDL - International Digital Library Of Technology & Research Volume 1, Issue 5, May 2017
Available at: www.dbpublications.org
International e-Journal For Technology And Research-2017 Longitudinal tensile strength S11=SmVm+SfVm S11= 0.4* 280+ 0.6* 600= 472 MPa 3.
MATERIAL PROPERTIES
In the present study, the materials used for comparative study are Aluminum alloy and Carbon Fiber with Aluminum composite with volume fraction of 60:40 and final properties of composite are obtained by using rule of mixing. The Material properties used for finite elemental analysis for both the material are shown in Table 3 [12].
Table 3. Material Properties Material Properties
Aluminum alloy
Density(kg/m3) Young’s Modulus(MPa) Poisson`s Ratio Tensile yield strength (Mpa)
4.
2770
Carbon Fiber with Aluminum composite 2160
71000
207600
0.33
0.3016
280
472
COMPUTATIONAL MODELING
Fig. 1.Design of Knuckle Joint in CATIA 4.2 MESHING Meshing is done so that at each and every cell the equation are solved.Meshing improves the quality of the solution along with giving higher accuracy to the solution. [8]The modelled geometry isimported in ANSYS 16.2 Static Structural workbench for meshing. Meshing is done on Proximity and Curvature. Details of mesh is shown in Table 2.Table 2: Details about the meshing for Knuckle joint model. Min Size Proximity Min Size Max. Face size Growth size Max. size Nodes Elements
0.0250190 mm 0.0250190 mm 25.0190 mm 1.850 50.0390 mm 165134 105538
4.1 GEOMETRY The design being studied is knuckle joint which is modelled in CATIA V5R18 as shown in Fig. 1.In the design, the joints are boltedand the fork end is joined with the eye end with the help of knuckle pin as it acts as a bolt. The knuckle pin is secured between the two eyes by a tapper pin and collar.
Fig. 2. Mesh for Knuckle Joint 4.3 BOUNDARY
CONDITIONS
Knuckle pin, taper pin and collar is defined as fixed support. An axial load of 70 kN is applied at the end of the joint. Figure --- shows the boundary condition applied.
IDL - International Digital Library
3|P a g e
Copyright@IDL-2017
IDL - International Digital Library Of Technology & Research Volume 1, Issue 5, May 2017
Available at: www.dbpublications.org
International e-Journal For Technology And Research-2017
Figure 4(a) Distribution of Equivalent stress for Aluminium alloy Fig. 3. Boundary condition and load of 70 kN.
5.
RESULTS& DISCUSSIONS
5.1 Maximum equivalent (Von-Mises) stress: Figure 4(b) Distribution of Equivalent stress for Composite application
From the numerical simulation analysis, the maximum equivalent stress was found to be 83.56 MPa which is less than the allowable stress considering factor of safety 2.The ANSYS analysis indicated the maximum stress experiences at the interface between the pin, eye-end and the fork end. The structure therefore has a safety factor of almost 2 for this loading and failure mode. The structure is therefore satisfactory for carrying the axial load of 70kN. With the introduction of Carbon-fibre aluminium for the analysis, there is insignificant change in equivalent stress occurred. Figure 4 (a and b) shows the distribution of equivalent stress.
IDL - International Digital Library
Directional deformatio n-
Figure 5(b) Distribution of Equivalent stress for Composite application
ANSYS software has a unique module which enables to measure the amount of deformation i.e. change in length of the joints. It can be seen that maximum deformation is experienced at the end of the joints. The above results shows that the maximum displacement at the end of the joints is around 0.096669 mm in case when aluminium alloy is used. With the introduction of composite material there is noteworthy reduction in the value of maximum directional deformation of 0.025417 mm. The analysis shows that the deformations experienced by the components are less when composite material is applied and can be used safely for the application even for longer time duration as compared to when aluminium alloy is used. Figure 5 (a and b) shows the distribution of directional deformation.
4|P a g e
Copyright@IDL-2017
IDL - International Digital Library Of Technology & Research Volume 1, Issue 5, May 2017
Available at: www.dbpublications.org
International e-Journal For Technology And Research-2017 64
%
CONCLUSION AND FUTURE SCOPE
Fig. 5(a) Distribution of Directional Deformation for Aluminium alloy
Weight reductionApart from the other benefits, the biggest benefit, however, is mass reduction for using composite materials. The mass of the system when aluminum alloy is used was 6.215 kg. When composite material is used the weight got reduced to 4.8464 kg. So reducing weight can provide a great help towards the modern automobile industry which are focusing on weight reduction. The software based results are summarized as followsTable Comparison for aluminum alloy and composite applications Parameter Load Alumin Com % (N) um posit chang Alloy e e appli catio n Equivalent 70000 83.56 84.9 -1.6% stress 02 (MPa) Directional 70000 0.0966 0.02 73.7 Deformati 69 5417 % on (mm) Mass (kg) 6.215 4.84 22.02
IDL - International Digital Library
The FEM analysis is done for the knuckle joint. To analyse the stress, mesh was developed for the knuckle joint. Due to application of composite material there has been a negligible change in stress value but directional deformation and weight of the system got reduced by 73.7 % and 22.02% respectively. Though the cost of production of Knuckle Joint with the composite material is relatively high but the result shows significantly low deformation. So, with the use of composite material in, the life of the Knuckle jointincreases. Also, the weight of the Knuckle Joint decreases. Thus, Knuckle Joint with this composite material can be used in places which require replacement of tool in large interval of time. Further study can be carried out in this regard in order to obtain more accurate results by performing the above analysis in the ANSYS Composite domain.
REFERENCES [1] Gupta, R.S. Khurmi, J.K. (2008). A textbook of machine design (S.I. units) [2]V.B. Bhandari, Design of Machine Elements, McGraw Hill Education, ISBN: 0-07-0681791-1, 2014. [3]Knuckle Joint – Introduction, Parts and Applications. Retrieved fromhttp://mechteacher.com/knuckle-joint/ [4] Knuckle Joint – Introduction, Parts and Applications. Retrieved fromhttp://nptel.ac.in/courses/Webcoursecontents/IIT%20Kharagpur/Machine%20design1/p df/Module-4_lesson-2.pdf [5] VirajRajendra Kulkarni, Amey Gangaram Tambe., “Optimization and Finite Element Analysis of Steering Knuckle”. Altair Technology Conference.
5|P a g e
Copyright@IDL-2017
IDL - International Digital Library Of Technology & Research Volume 1, Issue 5, May 2017
Available at: www.dbpublications.org
International e-Journal For Technology And Research-2017 [6] Kirpal Singh, Automobile Engineering, New Age publication. [7] PurushottamDumbre, A. K. Mishra, V. S. Aher and Swapnil S. Kulkarni, “Structural Analysis of Steering Knuckle for Weight Reduction”, International Journal of Emerging Technology and Advanced Engineering. 4(6): 221- 226. [8] Nishant Vibhav Saxena and Dr. Rohit Rajvaida, “Study & Analysis of Knuckle Joint With the Replacement of Material By Using Teflon”, Int. Journal of Engineering Research and Application, Vol. 5, March 2015, pp. 67-72. [9] Mohd Azizi Muhammad Nora B., Helmi Rashida, Wan Mohd Faizul Wan Mahyuddinb.. ”Stress Analysis of a Low Loader Chassis. International Symposium on Robotics and Intelligent Sensors” 2012 (IRIS 2012), Procedia Engineering, 41: 995-1001 [10] Grzegorz Kolzalka, G., Debski, H., Dziurka and M. Kazor, M. 2011. “Design of a Frame to a Semi Low Loader.” Journal of KONES Powertrain and Transport. 18(2). [11] Rohit Ghosh,Sushovan Ghosh, Tanuj Srivastava and Dr.Rabindra Nath Barman, “Design and Manufacturing of Laminated Spring: A New Approach Based On Composites” International Journal of Engineering and Technology, 9: 14381451. [12]http://www.azom.com/article.aspx?ArticleID= 2863
IDL - International Digital Library
6|P a g e
Copyright@IDL-2017