INVESTIGATION OF GASKET SEALING BEHAVIOUR OF AN ALL-ALUMINIUM HIGH PERFORMANCE, NEW GENERATION PASSENGER CAR ENGINE UNDER EXTREME ENGINE OPERATING CONDITIONS

The increasing demand for higher specific power, fuel economy, Operating Costs as well as meeting global emission norms have become the driving factors of today’s product development in the automotive market today. Substitution of high-density materials and more precise adjustment of material parameters help in significant weight decrease, but it is accompanied by undesirable cost increase and manufacturing complexity. This becomes a challenge for every automotive engineer to balance the above parameters to make a highly competitive design. This work is a part of the Design and Development of 2.2 L, 4 Cylinder TCIC Diesel Engine for a complete new monocoque vehicle platform, focused on automotive passenger car application. This paper explains the selection of a suitable cylinder head gasket technology for a lightweight engine that acts as a sealing interface between the cylinder block and cylinder head. The decision to select an aluminum alloy for both cylinder block and head still makes the design thought-provoking to meet the high peak firing pressure requirements of around 190 bar. The paper discusses the details involved in the selection of combustion bead profile, placement of bead profiles, design parameters for coolant and lubricant cross passages between block and head, need for required stiffness in the structural components to ensure a proper load transfer path, and basic sealing requirement with very minimal cylinder deformation. Head Block Compound Simulation, Contact Pressure Analysis, and Bore Distortion analysis simulations have been performed and the results are discussed in detail. Appropriate functional evaluation results, durability observations, and reliability validation results are explained. The holistic approach has helped in the design and development of the cylinder head gasket which had been successfully validated and productionized.