MODIFICATION IN DESIGN OF CYLINDER HEAD GASKET FOR REDUCTION IN BORE DISTORTION AND TO ACHIEVE OPTIMUM CONTACT PRESSURE

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 7, Issue 5, September October 2016, pp , Article ID: IJMET_07_05_026 Available online at Journal Impact Factor (2016): (Calculated by GISI) ISSN Print: and ISSN Online: IAEME Publication MODIFICATION IN DESIGN OF CYLINDER HEAD GASKET FOR REDUCTION IN BORE DISTORTION AND TO ACHIEVE OPTIMUM CONTACT PRESSURE Satish Anande M. Tech Mechanical-CAD/CAM, SGGSIE&T, Nanded, Maharashtra, India Amit Chaudhari Manager-R&D, Greaves Cotton Limited, Chikalthana MIDC, Aurangabad, Maharashtra, India Dr. M.K. Rodge Associate Professor, Production Engineering Department, SGGSIE&T, Nanded, Maharashtra, India ABSTRACT Cylinder head gasket is one of the most important components in order to produce effective seal. It is always important to select the proper material for the cylinder head gasket so that it should not affect on the other components of the engine while assembling. Structural steel is the commonly used material for the cylinder head gasket. Generally nonlinear analysis is performed in order to produce more accurate results. Most of the time we have to face the problem of breakage of gasket while tightening the bolts since we have to apply sufficient bolt load for the proper sealing. Sometimes modification of the shape of the cylinder head gasket is also required to achieve flexibility in the model and to avoid the breakage during tightening of the bolt. In this paper we have considered the multilayer cylinder head gasket of single cylinder diesel engine for the analysis. Nonlinear analysis for the cylinder head gasket is performed to reduce the bore distortion as well as to achieve the optimum contact pressure on the cylinder head gasket. Modeling has done in the CRE-O 2.0 and for the analysis ANSYS 15 software is used. Key words: Bore Distortion, Contact Pressure, Multilayer Gasket, Nonlinear Analysis, Structural Steel Cite this Article: Satish Anande, Amit Chaudhari and Dr. M.K. Rodge, Modification In Design of Cylinder Head Gasket For Reduction In Bore Distortion and To Achieve Optimum Contact Pressure. International Journal of Mechanical Engineering and Technology, 7(5), 2016, pp

2 Modification In Design of Cylinder Head Gasket For Reduction In Bore Distortion and To Achieve Optimum Contact Pressure 1. INTRODUCTION A cylinder head gasket is required to form a seal between the cylinder head and block of a petrol or diesel engine. It is an integral component of the IC engine and it is required to perform many functions during engine operation. Cylinder head gasket is the important component of the engine to avoid leakages. Cylinder head gasket is located between the cylinder block and cylinder head. Its purpose is to seal the cylinder in order to get maximum compression and to avoid leakages. The head gasket should maintain the seal around the combustion chamber at peak operating temperature as well as pressure. The gasket must seal against air, coolants, combustion and also engine oil at their respective peak operating temperature and pressure. The material used and design employed must be thermally and chemically resistant to the various products of combustion, the different chemicals, coolants and oils are used in the engine. Gideon Daka Finuma [1] has studied that to avoid leakages of gases, cooling fluid it is required to give proper pretension to the bolt in order to increase the sealing efficiency. Proper design of gasket is also required for best sealing. The distribution of contact pressure on gasket is checked for different loading conditions like cold assembly, hot assembly, cold start, hot firing and is elaborated by calculations obtained by finite element method. Parametric analysis has done by applying proper pretensioning force on bolt and results are compared at cold assembly and cold start conditions. The variation in results indicate that maximum contact pressure is obtained at one particular location by applying only bolt pretension and maximum contact pressure region has changed when we consider the thermal loading condition. Jonathan Raub [2] has explained that it is very complicated to model the cylinder head gasket joint due to nonlinear nature of cylinder head gasket material. Linearization of the gasket material can give significant error in the solution results. The one dimensional nonlinear approximation has done by using SOLID185 element as a gasket material option. It sufficiently captures the response of nonlinear materials and also it maintains the practical solution time for the large model like joint of multicylinder head gasket models. So we get the idea of the model building and assembly process of creating the head gasket joint model, explain the nonlinear nature of the material for the given model and the comparison of the model s result with experimental measurements. Mirza Baig and Cherng-Chi Chang[6] have explained that in the multilayer cylinder head gasket durability analysis, normal and relative shear motion between the cylinder head and cylinder head gasket, cylinder head gasket and cylinder block and different layers of gasket in the analytical model is considered in order to calculate the stresses accurately. In this work the analytical method has been developed to calculate multilayer steel head gasket stresses at engine operating condition. In the ABAQUS software, gasket element is developed to model the each layer of multilayer cylinder head gasket. Gasket layers are bind together according to configuration of head gasket. Load deflection curve is used to represent the stiffness of the gasket model. Analysis of cylinder head gasket has done by using two approaches i.e. modeling of each layer of gasket in stacked GASKET element and modeling of gasket layers by using continuum element. Continuum element model takes twice time to run the analysis as compared to stacked GASKET element model. For the proper pretensioning of the bolt four holes are provided to the cylinder head gasket, cylinder head and cylinder block of the engine. Table 1 List of parts used in the assembly Sr. No. Parts used in the assembly Parts Material used 1 Cylinder head gasket Structural steel 2 Cylinder head Aluminium alloys 3 Cylinder block Gray cast iron 4 Crankcase Aluminium alloys 5 Nut Structural steel 6 Stud Structural steel editor@iaeme.com

3 Satish Anande, Amit Chaudhari and Dr. M.K. Rodge 2. FINITE ELEMENT ANALYSIS 2.1. Finite Element Model For the analysis of cylinder head gasket and cylinder bore distortion, mesh generation is carried out in ANSYS software after importing the geometry from CRE-O software. Mesh generation for whole assembly has done by using 4 mm mesh size except cylinder head gasket. For the cylinder head gasket and at the contact region of cylinder head as well as cylinder block 1 mm mesh size has given. A total of nodes and elements were created. Table 2 Quality criteria for meshing Parameter Criteria Min element size 0.03 mm Max element size 4 mm Shape checking Aggressive mechanical Aspect ratio Jacobian ratio 1 Figure 1 Meshed model of the assembly 2.2. Material Properties Material property must frequently be the approximated in FEM. There is an accepted degree of variation in young s modulus of even the most standard of engineering material editor@iaeme.com

4 Modification In Design of Cylinder Head Gasket For Reduction In Bore Distortion and To Achieve Optimum Contact Pressure Material Young s Modulus (N/mm 2 ) Table 3 Material properties Poisson s ratio (K) Density (kg/m 3 ) Yield strength (N/mm 2 ) Ultimate strength (N/mm 2 ) Steel 2.10* Grey cast 1.1* iron Aluminium 7.1* Boundary conditions Combustion Temperature: Temperature of C is applied in steady state thermal module and the solution is imported in static structural module to perform the analysis Fixed Support: The required geometry of cylinder head, cylinder head gasket, cylinder block and crankcase is to be fixed for proper analysis and to get accurate results Stud Pretension: For applying the stud pretension, Z co-ordinate of local co-ordinate system should be along the axis of stud. Stud pretension of 40,000 N is applied to each stud Standard earth gravity: Standard earth gravity has applied to whole assembly in the downward direction to the entire assembly Combustion Pressure: The pressure of 80 bars is applied internally at the barrel and cylinder head gasket surface Results obtained after analysis The contact pressure obtained for the cylinder head gasket is as shown below. The contact pressure should be more in order to obtain best sealing. Figure 2 contact pressure on the cylinder head gasket The following deformation plot shows the effect of single layer gasket on the bore distortion. The bore distortion should be minimum for the best sealing editor@iaeme.com

5 Satish Anande, Amit Chaudhari and Dr. M.K. Rodge Figure 3 Cylinder bore distortion 3. MODIFICATION OF CYLINDER HEAD GASKET Modification of cylinder head gasket has done to increase the contact pressure and to decrease the bore distortion. In this work we have used multilayered cylinder head gasket to achieve above requirement. Figure 4 Modified multilayer cylinder head gasket If we use modified cylinder head gasket in the assembly and perform the nonlinear analysis by keeping the same boundary conditions then we will get following results for contact pressure on cylinder head gasket and the bore distortion. Figure 5 Contact pressure on the cylinder head gasket editor@iaeme.com

6 Modification In Design of Cylinder Head Gasket For Reduction In Bore Distortion and To Achieve Optimum Contact Pressure Figure 6 Bore distortion by using modified CYLINDER HEAD gasket 4. EXPERIMENTAL VALIDATION FOR CONTACT PRESSURE AND BORE DISTORTION FOR 600 CC DIESEL ENGINE For the contact pressure experimental validation has done by using Fuji film. Fuji film is the prestressing sensitive film. It works like litmus paper. It contains thin polyester film which consists of layer of tiny microcapsules. On the application of force the film causes the microcapsules to rupture, produces as instantaneous and permanent high resolution variation of pressure across the contact area. The color intensity created is directly related to the amount of the pressure applied on the contact region. If the intensity of the color is more then it shows more contact pressure. For experimental analysis, Fuji film was inserted between cylinder head gasket and cylinder head. Experimental validation of cylinder bore distortion has done by using bore gauge. 5. RESULTS AND CONCLUSION The contact pressures on the cylinder head gasket and bore distortion are obtained with FEA using CAE tool ANSYS. Then it has checked experimentally. If we compare the actual results and simulated results, it shows the percentage deviation less than 10% between the results. Thus FEA method can be used for solving such a type of problems. Sr. no Type of Single layer Multilayer Table 4 Average contact pressure on cylinder head gasket Actual contact pressure (MPa) Contact pressure in ANSYS software (MPa) Percentage deviation between actual and simulated results % % From the table 4. percentage deviation between actual and simulated results is less than 10% editor@iaeme.com

7 Satish Anande, Amit Chaudhari and Dr. M.K. Rodge Sr. no Type of Single layer Multilayer Actual Bore deformation (µm) Table 5 Bore distortion results Bore deformation in ANSYS software (µm) Percentage deviation between the actual and simulated results % % From the table 5. percentage deviation between actual and simulated results is less than 10%. Table 6 Comparison of initial results and results after modification of for 600 cc diesel engine Sr. no. parameter Single layer 1. Contact pressure (MPa) Modified Multilayer Percentage change in results % 2. Bore deformation(µm) % From the above table, it can be concluded that by modifying cylinder head gasket contact pressure can be increased by 20 % and bore deformation can be reduced by 6.89%. REFERENCES [1] Gideon Daka Finuma, Analysis of Cylinder Head Gasket Sealing Under Engine Operation Conditions, Toronto, September 8, [2] Jonathan Raub, Modeling Diesel Engine Cylinder Head Gaskets using the Gasket Material Option of the SOLID185 Element, Cummins, Inc. [3] Pavan P. Jorwekar, Cylinder Head Gasket Contact Pressure Simulation for a Hermetic Compressor, Kirloskar Copeland Limited, [4] Jef Scot Eagleson, Head Gasket Finite Element Model Correlation, University of Windsor, [5] M.Srikanth and B.M.Balakrishnan, Cylinder Head Gasket Analysis to Improve its Thermal Characteristics Using Advanced Fem Tool, International Journal of Machine and Construction Engineering, 1 Mar [6] Mirza Baig and Cherng-Chi Chang, Multi-Layer Steel Head Gasket Durability Analysis using Stacked GASKET Element Model, General Motors Corporation, Pontiac, MI [7] Shinji Fukase, Tsuyoshi Takahashi and Jouji Kimura, Experimental Study of Static and Dynamic Behavior of the Cylinder Head Gasket in a Turbocharged Diesel Engine with Intercooler, Isuzu Motors Ltd, SAE Technical paper [8] Mark Kincart and Jeffrey Stark, Determining reasons for head gasket failures in air-cooled engines with a simple testing methodology. [9] G. Krishnamoorthi, K.Srinivasan, G.Praveenkumar and R. Siddharth. Cylinder Deactivation on Two Different Cubic Capacity Engine, International Journal of Mechanical Engineering and Technology, 7(1), 2016,bpp [10] Utsav Khan, Snehaditya Sen, Soumya Dey, Adriyaman, Banerjee. Development of Multi Cylinder CRD- I Engine To Meet Euro VI, Emission Norms, International Journal of Mechanical Engineering and Technology, 7(1), 2016, pp [11] Mike Kestly, Frank Popielas, Dieter Grafl and Alfred Weiss, Accelerated Testing of Multi-Layer Steel Cylinder Head Gaskets, Dana Corp, SAE Technical paper editor@iaeme.com