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The exhaust manifold heat shield is made of different material layers and is bolted to the engine exhaust manifold. The exhaust manifold heat shield has been identified as a potential major noise contributor among the engine components during normal operation, which is to protect nearby components from damage due to high heat. To reduce the noise radiated from the exhaust system, a thermal acoustic protective shield (TAPS) has been developed to act as a partial acoustic enclosure. This paper will discuss the importance of controlling NVH and what can be done design-wise to improve the TAPS characteristics. The paper discusses the impact of damping and vibration, how they are modeled. Further the present study analyzes the radiated sound pressure level (SPL) of a thermal acoustic protective shield by using the finite element analysis (FEA). The analyses are performed using the fully coupled structural-acoustic method and the sequentially coupled structural-acoustic method.

Today, Computer Aided Engineering (CAE) has become an essential part in the development of Thermal-Acoustical Protective Shields (TAPS). As presented three years ago, such a theoretical approach has been able to reduce the development cycle of TAPS while simultaneously reducing costs. Using the approach as previously presented gave us an opportunity to learn more and upgrade the approach with more modules. These modules are focused not only on obtaining better accuracy but also adding information about processes and function of the TAPS. Besides those parameters we are now able to look up-front into the visual appearance of the product using simulation techniques. This paper will describe this updated CAE approach, with a main focus on the new added techniques and modules. This paper will also describe how the results of the approach are used in the development of new TAPS and how we verify the theoretical results by the means of experimental techniques.

Thermal Acoustic Protective Shields (TAPS) serves dual purpose. They provide a thermal barrier, which protects sensitive components from the exhaust manifold radiated energy. They also act as an acoustic insulator, which reduces the amount of sound power transmitted from the engine to the environment. The design of multi layered TAPS has, until recently, relied on trial and error or simplified numerical analyses. The following work describes efforts to develop a comprehensive numerical methodology for the initial forming of the components, which accounts for most of the physics of the problem. The simulation accounts for the complete forming operations of the part, i.e. edge folding, multi layer assembly, edge crimping, beading, and final forming. Non-linear effects are accounted for such as interlayer frictional dissipation, plastic anisotropy and self-contact.

Today, detailed up-front theoretical analysis is essential to shorten development time and decrease costs. Multi-Layer Steel (MLS) cylinder head gaskets we use are coated with a very thin rubber-like coating plus featuring other complicated geometric features, which makes the analysis a difficult task. With the Proteus® software package we define a project, which consists of the manufacturing process of the main elements (like embossments or wave stopper) up to the functional parameters (like loading behaviour and durability). This paper presents how we start with the single layer element simulation and transfer the information into the multi-layer analysis. Both of those cases are 2D-axis-symmetrical. Further the developed information will be used for 3D simulations in other software packages Besides the project approach in Proteus® we will briefly explain the theoretical basis. For that we start with the Method of the Local Functionals (MLF), a modification of the traditional FEM.

Today, Computer Aided Engineering (CAE) is standard in the up-front gasket development. As presented three years ago, it helps to reduce the development cycle and at the same time the development costs. With the success in using this approach, we received new requirements from the customer requesting for more and better details so that the project can be completed within the same time frame. The theoretical advancement and the drastic changes in the computer hardware technology along with lower costs aided in fine tuning our previously developed approach and adding new features. So we upgraded our specialized Proteus® software for the element study and extended it into the multi-layer 2D case. Further, more we detailed and improved the simplified 3D-model module as well as the whole bank 3D-model. A very important addition is the flow/thermal analysis to create the thermal map with our models.

MLS (Multi-layer steel) CHG ( Cylinder Head gasket) designs play a major role in today's sealing approach for internal combustion engine. However, as a member between cylinder block and cylinder head, it not only has a sealing function, but also influences the hardware structure. The knowledge of their interaction is critical to fulfill all necessary requirements. This paper discusses different MLS CHG designs and how they influence the hardware's structure while maintaining the seal of the assembly. Therefore, we investigate major parameters like sealing stress, sealing gap lift-off, bore distortion and etc. A comparison is made between different designs, using experimental data as well as finite element analysis. Because of the vast number of designs and their interactions between the hardware and gasket, the focus is on basic trends of their influences.

Today, Computer Aided Engineering (CAE) is a feature that becomes more and more essential in the development of Thermal-Acoustical Protective Shields (TAPS). The development cycle of TAPS needs to be reduced while simultaneously reducing costs. The performance, functionality and visual appearance need to be improved as well. This paper will describe our general CAE approach, which is based on the use of different CAD systems and Finite Element Analysis (FEA). We will describe how we use the results of our approach in the development of new TAPS. Because this approach is based on the knowledge of the parameters that exist and how they influence a TAPS function, we will first discuss the most important of these parameters. Here we split our discussion into ‘What is a TAPS, ‘What are the main steps of making a TAPS - Designing, prototype’, and ‘How a TAPS works in an engine’. We will then explain the different FEA utilization's.

Today, Computer Aided Engineering (CAE) is a feature that is essential in gasket development. The reasons are that we need to reduce the development cycle, and that we need simultaneously to reduce our costs. This paper and presentation will describe our general CAE approach, which is based on the Finite Element Analysis (FEA) and their modifications. We will describe our approach and how we use the results in the development of new MLS gaskets. Because this approach is based on the knowledge of parameters that exist and how they influence a gasket's function, we first of all will discuss the most important of these. Further we will explain the FEA utilization. We will also describe some special features of different software and subroutines (like “Proteus®”). Then, we will further describe how we obtain information about the beading process, the durability, the sealing gap oscillation, etc. Finally, we will give a short overview about some modifications compared to the classical FEA.

Accelerated testing techniques for cylinder head gaskets have become absolutely necessary because of developments at engine manufacturers including: shorter engine development times, high costs of vehicle and dynamometer testing, new material generations for engine components, and new engine generations and longer engine life This paper will describe two accelerated test methods for Multi-Layer Steel (MLS) cylinder head gaskets and will discuss the most important parameters which influence MLS cylinder head gasket functional performance. We will describe how these parameters have been duplicated in the laboratory using the accelerated tests: the Bending Simulator and the Hydraulic Pulsator. The test method results have been confirmed based on detailed metallurgical analysis of MLS gaskets; comparing field (dynamometer and vehicle) tested gaskets to those gaskets evaluated on accelerated tests.