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Increasing use of engineering thermoplastics in the applications such as load bearing automotive components necessitates accurate characterization and material modeling for predicting part performance using finite-element simulations. Uniaxial tensile test data on glass filled thermoplastic resins exhibit highly nonlinear deformation with no clear demarcation between elastic and plastic regions. Hence, the estimation of modulus and yield stress values, required for the finite element analysis, is invariably through the subjective interpretation of the CAE analyst, which may not be consistent and unique. Use of parameters such as tangent modulus, yield stress and the post yield data calculated at 0.2% strain for finite element computations does not yield good correlations with experimental values. This paper outlines an alternate approach for evaluating material parameters for short glass filled engineering thermoplastics.

The combination of multi purpose software with powertrain specific application codes allows highly flexible simulation models, which are independent on the specific engine concept. Related to the requests those models may be refined or simplified during the simulation process. Finally a fully coupled 3D dynamic simulation including flexible components is performed to assess the engine crankshaft's durability. To take into account the stiffness of the cranktrain components and the cylinder block at first a linear Finite Element Analysis (FEA) simulation is performed. Via modal reduction the complete deformation order information of the FEA simulation are reduced to the necessary information for the dynamic Multi Body System (MBS) simulation [1, 2]. All main boundary conditions of the system, e. g. gas forces, oil temperature or driveline application are taken into account.

The objective of the present work is to establish a validated simulation methodology for air cooling of batteries that can be used in the industrial design process. Therefore an experimental test rig was set up using a pack of prismatic batteries. The flow field is analysed using Particle Image Velocimetry and pressure measurements. First numerical flow calculations focus on the 3D gap flow. The results display a detailed account of the various flow phenomena and their scales that contribute to the complex flow problem of air cooled batteries and they highlight the technical challenges to obtain homogeneous cooling.

CAE tools have been broadly used to capture and predict interactions between dummies and airbags in detail with the advantages of less preparation time for test set-up and less variability in results especially during airbag deployment tests with dummies out of position. But, the time spent to fold airbag mesh, validate CAE airbag models to experiments and long turn-around times have often been a deterrent to fully adopting CAE tools as a effective way to develop airbag performance. It has been a few years since MADYMO implemented Computational Fluid Dynamics, or CFD into an airbag deploying algorithm. In the early stage of MADYMO CFD, there were issues such as a restriction on the maximum number of Euler cells and instability of unfolding airbags, however, with the introduction of MADYMO V6.2. it has improved CFD functionalities (i.e. more realistic predictions and more stable and accurate simulations).

This paper will show the growth of the Global 4x4 market ( Figure 1), and define terms for 4x4, 4WD and AWD. This will allow a way to organize the data and show the growth trends of the AWD segment. This growth can be seen in Figure 2. From this point of view, the vehicle, and technology differences will be shown, both with physical pictures, and schematic architecture diagrams. The focus will be the US 4WD and AWD market from 1997 to 2004, when a significant change occurred from 4WD to AWD architectures. Figure 1 This paper will document the changes that have occurred to bring about the distinct shift towards AWD car based vehicles from truck based 4WD vehicles. It will be clear why the terms were defined as they were when the architectural differences are shown schematically. Figures 25, 26, 27 and 28.

Much energy is lost through excess air flow in and out of process heating equipment. Energy saving opportunities from managing air flow include minimizing combustion air, preheating combustion air, minimizing ventilation air, and reconfiguring openings to reduce leakage. This paper identifies these opportunities and presents methods to quantify potential energy savings from implementing these energy-savings measures. Case study examples are used to demonstrate the methods and the potential energy savings. The method for calculating savings from minimizing combustion air accounts for improvement in efficiency from increased combustion temperature and decreased combustion gas mass flow rate. The method for calculating savings from preheating inlet combustion air consists of fundamental heat exchanger and combustion efficiency equations. This method accounts for the reduction of combustion air flow as fuel input declines, which is often neglected in many commonly-used methods.

This paper describes software developed by Wisconsin Industrial Assessment Center (IAC) for calculations of energy savings that can be obtained by installing adjustable frequency drives (AFD). Regression models for estimating power used at different loads with and without AFD were developed. Actual data for power use is logged and the power use with the AFD is estimated. The two resulting graphs for power use are compared. The difference in the areas under the two curves is the energy savings.

Productivity is a significant issue in the US auto industry that is often viewed as the success or failure that a vehicle assembly plant can make or break their production schedule. In other words, productivity is often looked at in terms of the number of assembled vehicles produced per year. While high production volume is an important indicator in a manufacturing environment, it certainly does not necessarily imply high productivity. By definition, Productivity is the ratio of output (number of vehicles produced) divided by all input resources such as labor, material, capital, overhead, health and energy costs. Improvement in productivity can be achieved in two ways: a reduction of inputs while output remains constant, or an increase in output while inputs remain constant. Energy is the single most controllable cost parameter in the input parameters of the productivity equation.

Finite element based stress analysis and fatigue predictions are practiced routinely in automotive body structural design and development. The accuracy of these simulation results is not fully understood or at least not well documented. Automotive body structures have many kinds of notches, metal thinning due to stamping and cold working etc. Modern fatigue assessment tools do take into account many of these complexities by Neuber corrections, mean-stress correction, critical plane selection, etc. Other challenges exist in the sensitivity to element quality, including warpage, size, element type, interpretation of results, etc. This case study is based on static loading and accelerated fatigue test conducted on a front-end body buck. The stress and fatigue correlations are designed to build confidence in the model and load inputs. The fatigue results are intended to reproduce durability issues that developed during a proving ground test and were then used to verify potential fixes.

The Plastic Valve Cover System (PVCS) should provides a leak proof seal to the cylinder head under engine temperature, isolate the vibrations transmitted from the engine through the cover to the environment, control the crankcase pressure and house the device to separate oil from the blow-by gas. In order to increase the stiffness of PVCS, short glass fibers and minerals are added during the injection molding of the plastic valve cover. The presence of the fibers results in a component with highly anisotropic thermo-mechanical properties that was not accounted in the previously approach [1]. This paper describes the updated CAE approach with the incorporation of the short fiber anisotropy into the design of cylinder head valve covers.

Industrial motor-driven systems consume more than 70% of global manufacturing electricity annually and offer one of the largest opportunities for energy savings. System optimization techniques through the application of existing, commercially available technologies and accepted engineering practices typically achieve energy savings of 20% or more for these systems across all industrial sectors. The optimization opportunities for steam systems are at least equal or greater. Despite the potential benefits, energy savings from these industrial systems have remained largely unrealized by US industry. This paper presents the argument that unless energy efficiency is institutionalized, it will be viewed by corporate managers as something different than the effective and efficient use of labor and material resources. If this institutionalization does not occur, the potential benefits will never be achieved or sustained.

Holographic interferometry has been successfully employed to characterize both static and dynamic behavior of diverse types of structure under stress. Double-exposure pulsed holographic interferometry has been extensively used in performing the vibration analysis and qualitative investigations of deformation of the non-stationary objects. One of the most important advantages of this technique is that it can be used for quantitative measurements of the transient processes (e.g. shock wave propagation). However, in conventional double-pulsed interferometry it is sometimes difficult to get phase information from a single set of holograms. Applying two-reference beam recording set-up to double-exposure pulsed holographic interferometry makes it possible to obtain phase-shifted interferograms from a single interferogram of the tested object and retrieve the phase information for OPD (optical path difference) map creation.

Many types of three dimensional mechanism (3D-mechanism) are used in modern industry. Specially, in automation technology, coordinate measuring machines (CMMs) play the key role. With the improvement of measurement accuracy conventional coordinate measuring machine (CMM) can’t meet the demand of 3D measurements of fine parts, so Nano-CMM (Coordinate Measuring Machine with nanometer resolution) appears in the world. This paper presents a novel structure design of Nano-CMM. The new structure named symmetrical-bridge is developed based on the analysis of conventional Nano-CMM. Compared with Nano-CMMs called rectangular-bridge and arch-bridge, this new structure performs less static deformation and provides higher accuracy under the same load. The analysis and comparison of three Nano-CMMs were made through ANSYS software, so it can be easily concluded that this new structure not only has great static rigidity but also dynamic rigidity.

In view of the fact that quality control is becoming more and more important and that the time for developing new mechanical parts decreases, optical nondestructive testing methods are very useful in industry. Especially, speckle interferometry. This paper describes three different interferometric nondestructive testing systems. A 3D-Holography-System, a Shearography-System and an Interferoscope are presented in order to enable a qualitative and quantitative evaluation. These three systems are used to examine a STAB-O-FOCS (an automatic Flap Opening and Closing System). The exterior of the strained housing is examined by holographic and shearographic means. Usually when measuring internal deformations the chassis has to be opened. With an interferoscope it is possible to examine inner structures through a small hole. Often such holes are available, for example an sensor which is inserted into the chassis of the STAB-O-FOCS.

Digital 3D profilometry is a non-contact, full-field, and fast method for 3D profile digitization. It has a relatively simple setup and acceptable measurement accuracy. Traditional phase shifting technique uses single frequency fringe pattern for coding the depth information and an unwrapping procedure is required for decoding. Usually, the object has to be a continuous surface without any disconnected part or large height discontinuities. In this paper, a new method of three-frequency fringe pattern is presented to measure objects with complicated structures, which have large surface height discontinuities, or contain separated components. Principles and procedures are described. Experimental application is given and limitations are discussed.

Energy dissipation due to micro-slip in joints is the primary source of damping in many vehicle and space structures. This paper presents results on how the surface topology may be modified to increase the energy dissipation in joints. An analytical solution for general forms of contact pressure of a one-dimensional micro-slip problem is presented. The solution indicates how the contact pressure should be distributed to maximize the energy dissipation. Two dimensional contact pressures are optimized using finite element methods in combination with numerical optimization methods and the results are used to modify the surface topology in bolted joints in order to increase the energy dissipation during loading. The predicted increase of energy dissipation is validated with physical testing. A direct result of the study is a washer with varying thickness increasing the energy dissipation in joints and hence the structural damping of joined structures.

Self Piercing Riveting (SPR) is widely used in the assembly of steel frame buildings and aluminium vehicle bodies. This paper investigates the dimensional variation resulting from the SPR process which until now has received little attention. The distortion of sheet metal in the normal and in-plane directions during joining are investigated separately. Firstly, the effects of the main SPR joining parameters: sheet thickness, joining sequence, riveting pitch and sheet rolling direction on the distortion in the normal or out of plane direction are presented for simple lap joints. Secondly, the distortion in the in-plane direction was investigated using simple flat, strip panels. It has been found that the dimensional variation in aluminium SPR joining can be significant and the major factors affecting the level of distortion are identified.

One of the main objectives of the automotive industry is to build more fuel efficient cars. The most dominant factor, among the many that determine fuel efficiency, is the weight of the vehicle. Any overall attempt to reduce weight involves all areas of the vehicle. Over the years the industry has addressed this need by developing new or modified materials and innovative production processes, combining these with one another and transforming them into viable production solutions. A very successful approach among the many things done is the use of structural metal adhesives, which have brought significant improvements in body shell rigidity and crash behavior. Traditionally, aluminum, steel and other metal parts were joined together with mechanical or thermal methods, such as rivets or resistance welding. But, structural adhesive is now an alternative that engineers consider very seriously. With any adhesive joint, the goal is to achieve as uniform a stress distribution as possible.

The highly competitive auto industry is looking for ways to reduce product development cycle time while meeting the corporate and government stringent vehicle performance requirements. Quasi-static or dynamic analytical fatigue life assessment of automotive structures consumes more time because of the use of long proving ground time histories and large finite element models with more than a million elements. A representative static load case that highlights all the durability concern locations is needed for making fast design iterations. This paper describes a simple technique to extract a static load case that correlates to minimum fatigue life at various locations of the body structure and the method of using this load case for fast iterations before validating the final design with fatigue analysis using full proving ground loads. The usefulness of this static load case in solving sheet metal and spot weld fatigue issues is demonstrated with an example.

In this contribution an efficient and modular method is presented to simulate fatigue crack propagation within the framework of linear-elastic fracture mechanics. The FEM code ABAQUS/Standard is used to simulate the load/displacement history of the considered 3D shell structure using 6-node triangular shell or continuum elements while the preprocessor ANSA is applied to employ remeshing. In order to efficiently simulate fatigue crack propagation in large finite element models a sub-model is extracted from the global model. The submodel is subjected to the kinematics given at the interface to the global model. Concerning fracture mechanics theory the stress intensity factor concept is applied. Stress intensity factors are calculated from the finite element mesh within an ABAQUS user subroutine using a novel variant of the well-known displacement correlation technique.