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General Motor's Corvette product engineering was given the challenge to find mass reduction opportunities on the painted body panels of the C6 Z06 through the utilization of carbon fiber reinforced composites (CFRC). The successful implementation of a carbon fiber hood on the 2004 C5 Commemorative Edition Z06 Corvette was the springboard for Corvette Team's appetite for a more extensive application of CFRC on the C6 Z06 model. Fenders were identified as the best application for the technology given their location on the front of the vehicle and the amount of mass saved. The C6 Z06 CFRC fenders provide 6kg reduction of vehicle mass as compared to the smaller RRIM fenders used on the Coupe and Convertible models.

Thermal Management Systems Symposium industry discusses latest regulatory impacts, applications to reduce engine emissions, conserve energy, reduce noise, improve the cabin environment, increase overall vehicle performance passenger, commercial vehicle industry.

Ever increasing specific power of diesel engines has put huge demand on effective thermal management of the pistons for the desired reliability and durability. The piston temperature control is commonly achieved by injecting cooling oil into piston galleries, but the design of the cooling system as well as the boundary conditions used in FEA simulations have so far relied mostly on empirical methods. A numerical procedure using 3D computational fluid dynamics (CFD) has therefore been developed to simulate the cooling process and to estimate the cooling efficiency of gallery. The model is able to predict the detailed oil flow and heat transfer in gallery, of different designs and engine applications, under dynamic conditions. The resulted spatially resolved heat transfer coefficient from the CFD model, with better accuracy, enables improved prediction of piston temperature in finite element analysis (FEA).

The work developed on this paper aims to compare different methods to evaluate bolted joints using finite element models. It will cover the theoretical background as well as the tools developed to improve the model creation process. The tools described on this paper comprises of scripts to automatically recognize holes on solid and shell meshes and create bolt connections as solid or 1D/0D elements, accordingly to the user needs. The solid bolt models are created together with all the information needed for the creation of the solver input deck and also the measuring surfaces used on post-processing evaluation. The reduction in modelling set up time increases with the number of bolted joints, being extremely efficient in large assembly models. This paper will also cover the method to evaluate the output from those bolted joints. This will include a study on fatigue as well as the contact formulations used on the solver algorithms.

The elevated strength of advanced high strength steels (AHSS) leads to enormous challenges for the sheet metal processing, one of which is hole punching operation. The total tonnage must be estimated at each trimming stage to ensure successful cutting and protect the press machine. This paper presents the effects of hole punch configurations on the punching force with the consideration of punch shape, cutting clearance and material grade. The hole punching experiments were performed with DP590, DP980, DP1180 and one mild steel as a reference. The punching force coefficient is defined and presents a negative correlation with the material strength based on the experimental data. Surface quality was examined to analyze the damage accumulation during the punching process. The cutting mechanisms with various punch shapes were revealed through an extensive finite element simulation study.

Induction noise, which radiates from the open end of the engine air induction system, can be of significant importance in reducing vehicle interior noise and tuning the interior sound to meet customer expectations. This makes understanding the source noise critical to the development of the air induction system and the vehicle interior sound quality. Given the ever-decreasing development times, it is highly desirable to use computer-aided engineering (CAE) tools to accelerate this process. Many tools are available to simulate induction noise or, more generally, duct acoustics. The tools vary in degrees of complexity and inherent assumptions. Three-dimensional tools will account for the most general of geometries. However, it is also possible to model the duct acoustics with quasi-three-dimensional or one-dimensional tools, which may be faster as well.

As part of the joint government/industry Partnership for a New Generation Vehicle (PNGV), Ford Motor Company, with the support of Alcan Aluminum Corporation and The Budd Company, conducted a feasibility study of the design and high volume manufacturing of a lightweight aluminum sport utility vehicle frame.

Interior compartment doors are required by Federal Motor Vehicle Safety Standard (FMVSS) 201, to stay closed during physical head impact testing, and when subjected to specific inertia loads. This paper defines interior compartment doors, and shows examples of several different latches designed to keep these doors closed. It also explores the details of the requirements that interior compartment doors and their latches must meet, including differing requirements from automobile manufacturers. It then shows the conventional static method a supplier uses to analyze a latch and door system. And, since static calculations can't always capture the complexities of a dynamic event, this paper also presents a case study of one particular latch and door system showing a way to simulate the forces experienced by a latch. The dynamic simulation is done using Finite Element Analysis and instrumentation of actual hardware in physical tests.

A technique which uses Finite Element Analysis (FEA) to derive important parameters involved in SEA (Statistical Energy Analysis) is discussed. Application of the method to a variety of structures has yielded good correlation with experimentally generated results. SEA parameters including Coupling Loss Factors (CLFs), modal densities, and subsystem equivalent masses were obtained. The technique has the advantage of incorporating structural detail to enhance SEA predictions at lower frequencies where global modes are important, and it can be applied early in the design phase since no hardware is required. With this study, SEA is more readily applied to structure-borne noise problems in vehicles.

The ever-growing concern to reduce the impact of transportation systems on environment has pushed automotive industry towards fuel-efficient and sustainable solutions. While several approaches have been used to improve fuel efficiency, the light-weighting of automobile components has proven broadly effective. A substantial effort is devoted to lightweighting body-in-white which contributes ~35% of total weight of vehicle. Closure systems, however, have been often overlooked. Closure systems are extremely important as they account for ~ 50% of structural mass and have a very diverse range of requirements, including crash safety, durability, strength, fit, finish, NVH, and weather sealing. To this end, a carbon fiber-reinforced thermoplastic composite door is being designed for an OEM’s mid-size SUV, that enables 42.5% weight reduction. In this work, several novel composite door assembly designs were developed by using an integrated design, analysis and optimization approach.

This paper describes a robust and user-friendly finite element analysis program, WRAPFORM, and its applications in sheet metal formability analysis for autobody panels. In a sheet metal forming die, a blank undergoes two distinct deformation processes: the forming of a binder wrap and the forming of the part. WRAPFORM is used to analyze binder wrap forming by calculating the surface shape of the formed binder wrap. It was developed using a "black box" approach. The mechanics of the problem, solution procedure and finite element methodology needed in the calculation model were made transparent to the user. A designer with little computer experience can use the program to obtain the binder wrap surface in one computer run. Applications of WRAPFORM have yielded useful results. In one application, the designers' intent was verified. In another, the calculated binder wrap surface shape was used in guiding the modification of the layout of a sheet metal forming die

Drawbeads have been playing an important role in deep drawing processes. The restraining force exerted by the drawbeads is important in enhancing the part formability. It is found that improper drawbead design will result in defects such as wrinkles and splitting. Thus, the drawbead geometry, especially its end radius, is a critical aspect in the die design. The present investigation focuses on the influence of the drawbead end radius and blankholder force on the sheet deformation patterns. The experimental results reveal that a drawbead with end radius equal to its cross sectional radius will cause severe deformation and wrinkling downstream of its end. With drawbead end radius twice the size of its cross sectional radius, the deformation in the downstream side of the drawbead end becomes smoother, hence improving the severe deformation and wrinkling. A higher blankholding force also suppresses the wrinkling near the drawbead end.

Recently, many authors have attempted to represent an automobile body in terms of experimentally derived frequency response functions (FRFs), and to couple the FRFs with a FEA model of chassis for performing a total system dynamic analysis. This method is called Hybrid FEA-Experimental FRF method, or briefly HYFEX. However, in cases where the chassis model does not include the bushing models, one can not directly connect the FRFs of the auto body to the chassis model for performing a total system dynamic analysis. In other cases when the chassis model includes the bushings, the bushing dynamic rates are modeled as constant stiffness rather than frequency dependent stiffness, the direct use of the HYFEX method will yield unsatisfactory results. This paper describes how the FRF's of the auto body and the frequency dependent stiffness data of the bushings can be combined with an appropriate mathematical formulation to better represent the dynamic characteristics of a full vehicle.

V-band joint was originally developed during World War II by the Marmon Corporation for use in the aircraft industry. The U.S. Military used Marman clamp to secure the atomic bombs during transport at the end of the Second World War.

A set of methods is described to calculate boundary conditions for thermal and mechanical finite element (FE) analyses and to assess and present the results of those analyses in a clear and understandable way. The approach utilizes a combination of engine simulation programs and an empirical database of engine measurements developed over many years. The methodology relies on the use of specialized FE pre- and post-processors dedicated to the analyses of engine components. Gas-side thermal boundary conditions for combustion chamber components are calculated using an engine simulation code for standalone FE analyses or for FE analyses directly coupled to the engine simulation code itself. Coolant side boundary conditions are calculated using multidimensional flow analysis (computational fluid dynamics). Boundary conditions in intake and exhaust manifolds are calculated using a one-dimensional gas dynamics code.

There are three criteria for an ideal ship-marine machinery noise analysis tool: It is applicable over a wide frequency range, it has modeling fidelity, and it is economical and can be used for design iterations. Vibratory energy from the machinery sources to the ocean follows 3-dimensional paths. Energy is attenuated by isolations, structural discontinuities, damping treatment, before radiated to the water. Traditionally, Finite Element Method (FEM), Boundary Element Analysis (BEM), and Statistical Energy Analysis (SEA) are used for noise analysis. FEM models can be constructed to follow complex machine geometry well. However, its applicable frequency range is limited by the practical mesh size. On the other hand, SEA can be used in the middle to high frequency ranges where the system modal density is adequate. The basic building blocks of a SEA model consist of plates, shells, and beams.

Rapid change is a way of life in Chrysler. Facing increasing competition, we realize that the traditional practices are no longer sufficient. Accordingly, a new process using simultaneous engineering (SE) teams in conjunction with reliability tools has been used to design and develop a new family of Chrysler engines. These SE teams include representatives from engine engineering, vehicle platform engineering, electrical engineering, manufacturing, reliability & service engineering, finance and suppliers. The SE teams maximize the use of up-front engineering tools, such as Finite Element Analysis (FEA), Digital Model Assembly (DMA), Variation Simulation Analysis (VSA) and Rapid Prototyping with StereoLithography (SLA), Laminated Object Manufacturing (LOM), etc. The new process combines these up-front engineering activities and the appropriate reliability testing as an integral part of the reliability growth process. It enhances the design decisions made with reliability.

First, a method for deriving the cyclic deformation and fatigue properties of the weld metal (that is also called ER70S-3 in AWS, American Welding Standard) is explained using solid bar specimens. Then, welded tube specimens were used with two symmetric welds and subjected to axial, torsion, and combined in-phase and out-of-phase axial-torsion loads.

This paper presents a measuring technique, a test result and a finite element analysis result of a surface temperature of rotary lip seals. A thermocouple embedded in the surface of a shaft and radio transmission systems provide wireless measurement for the temperature of the rotary shaft, which is driven up to 6000 rpm. Relationships between shaft temperature, lip temperature and sliding speed were shown. Torque of PTFE coated seals is about 23 % lower than that of conventional seals at 22 m/s. At that time, the shaft temperature of PTFE coated seals is about 7 K lower than that of conventional seals. And, Lip temperature of PTFE coated seals is about 1 K lower. In the analysis result, high temperature part of the shaft is larger than that of the lip, that is, heat is concentrated in the sealing edge of the lip. Temperature rise of the analysis result is consistent with those of the test result.

This paper expands the oral presentation the authors made at 2000 Brake Colloquium [1], and publishes, for the first time, the key concept and procedures of applying an advanced component mode synthesis method, the MacNeal method, in brake squeal simulations. The effectiveness and the efficiency of the overall approach are demonstrated and verified by direct FEA. In addition to squeal propensities and the unstable complex mode shapes, this paper also investigates different mode participation factors (MPF) - Component MPF and System MPF, and component participation factors (CPF). The paper also introduces Acoustic Component Participation Factors (ACPF). Application case studies are presented to demonstrate the commonalities and differences of those factors.