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Data-driven plant models are well established in engine base calibration to cope with the ever increasing complexity of today’s electronic control units (ECUs). The engine, drive train, or entire vehicle is replaced with a behavioral model learned from a provided training data set. The model is used for offline simulations and virtual calibration of ECU control parameters, but its application is often limited beyond these use cases. Depending on the underlying regression algorithm, limiting factors include computationally expensive calculations and a high memory demand. However, development and testing of new control strategies would benefit from the ability to execute such high fidelity plant models directly in real-time environments. For instance, map-based ECU functions could be replaced or enhanced by more accurate behavioral models, with the implementation of virtual sensors or online monitoring functions.

The Exhaust Noise is one of the major noise pollutants. It is well-known that for higher noise reduction, the engine has to bear high back pressure. For a race car, back-pressure plays a major role in engine's performance characteristics. For a given condition of engine rpm & load, conventional muffler has a fixed value of back-pressure and noise attenuation. Better acceleration requires low back-pressure, but the exhaust noise should also be less than the required (Norm) value (110 dBA). This contradicting condition is achieved here by using a ‘Butterfly Valve’ in this novel exhaust muffler. The butterfly valve assumes 2 positions i.e. fully open & fully closed. When the valve is fully closed, the noise reduction will be higher, but the back-pressure will also shoot up. When open, noise reduction will be less and so the back-pressure. So, when better performance is required, the valve is opened and back-pressure is reduced. The muffler is designed for a 4 cylinder 600 cc engine.

This study investigates using driver prediction to anticipate energy usage over a 160-meter look-ahead distance for a series, plug-in, hybrid-electric vehicle to improve conventional thermostatic powertrain control. Driver prediction algorithms utilize a hidden Markov model to predict route and a regression tree to predict speed over the route. Anticipated energy consumption is calculated by integrating force vectors over the look-ahead distance using the predicted incline slope and vehicle speed. Thermostatic powertrain control is improved by supplementing energy produced by the series generator with regenerative braking during events where anticipated energy consumption is negative, typically associated with declines or decelerations.

In diesel systems, compression ratio(CR) is one of the key parameters which plays an important role in its performance. The volume of air that is sucked into the cylinder and which will be further compressed in compression stroke depends on the swept volume due to the piston movement from Top Dead centre (TDC) to Bottom Dead Centre (BDC) within the cylinder. The increase in CR through increase in the swept volume without changing either cylinder or piston sizes and without altering the TDC position will be very useful. The author proposes two schemes based on variable ConRod (Connecting Rod) and Movable Crank Pin approaches to realize the increase in CR. The author also touches upon the scope of varying the CR in these schemes.

A method of predicting highway truck/tractor component lives based on warranty data is provided. This method incorporates computer modeling techniques into standard reliability analysis procedures to facilitate Reliability Estimation and Failure Prediction. Specifically, published truck/tractor usage data provided the basis for the computer modeling, and Weibull Distribution Analysis methods were utilized for Reliability Estimation. General considerations in the development of the computer model, and specific suggestions for the application of the method to vehicle applications other than highway truck/tractors are provided.

Condensate that forms on the air side surface of an evaporator can have a significant impact on the air side performance of brazed aluminum, louver fin automotive evaporators. Condensate can “bridge” the space between two adjacent fins or louvers and alter the flow of air through the evaporator, causing a change in the heat transfer and friction characteristics. This study attempts to determine how condensate drains from an evaporator in the hopes of improving the air side fin geometry and obtain an evaporator that retains a minimum amount of condensate. Using a table-top wind tunnel apparatus, qualitative observations of condensate draining from a single column of louver fins brazed to a refrigerant tube were made. The amount of condensate retained in an evaporator core was determined using the experimentally-verified dip test method.

The manufacturers of passenger cars increasingly assign development and production of complete subsystems to the supplying industry. A brake system supplier has to give predictions about system quality and performance long time before the first prototypical system is built or even before the supplier gets the order for system development. Nowadays, the usage of computer-aided system design and simulation is essential for that task. This article presents a tool designed to support the development process. A special focus will be on how to define quality. A formal definition of quality is provided, illustrated and motivated by two examples.

A transient numerical heat transfer model has been developed for the purpose of estimating the time-dependent temperature distribution in a heavy duty drum brake system. The model is based on a forward-difference explicit finite difference solution of the heat equation, in combination with a non-uniform pressure distribution for energy input, based on observed brake lining wear. Temperatures predicted by the model were compared to experimental dynamometer drum temperature measurements. The model was utilized to simulate a common industrial test for evaluation of brake drum resistance to thermo-mechanical fatigue cracking. Thermo-physical property variation and drum wall thickness were shown to exert a strong influence on the predicted temperature gradients and fatigue cracking susceptibility.

For the automotive industry the styling of headlamps become more and more important. Clear lens design with facetted freeform reflector represent the status quo of modern headlamps. Additionally the available construction volume decreases and at the same time the requirements to the light distribution increases. For that reason precise simulation of light distribution in an early stage of the development is absolutely necessary. It will be shown exemplary how these methods work and why their use is strongly recommended. The results can be compared with measurements conducted on existing headlamps and demonstrate the benefit of these methods. Due to more powerful computational models and increased computer capability these simulation tools will be improved even more in the near future.

This paper presents a review of the effects of fog on visibility during nighttime driving conditions and the factors influencing the performance of a front fog lamp. The effects on visibility due to beam pattern characteristics, mounting height, and lamp aim are studied using current mathematical models for fog veiling luminance, target luminance, and target contrast. A comparison is made of two different fog lamp photometry standards to show how each performs in terms of fog veiling luminance, target contrast, and glare for the opposing driver. The effects of varying the vertical aim of each fog lamp standard are studied in order to make conclusions about the correct lamp aim and tolerances required for fog lamp aiming. The effects of fog lamp mounting height and driver position are studied. Conclusions are made concerning optimum mounting height, aim, and beam pattern for fog lamps for vehicles with different driver positions.

This paper describes a new headlamp design evaluation and simulation program that provides greater freedom and improved efficiency in light distribution design, using either concave or convex lens and a reflector with a NURBS (Non-Uniform Rational B-Spline Surface), for one of its free surfaces. It also offers simulation results of light distribution designs using this program in order to produce various headlamps, including high-efficiency and flat headlamps, each with a concave lens, and a thin headlamp with a convex lens.

Textron Automotive Trim, Valeo Climate Control, and Torrington Research Company, with assistance from GE Plastics, have developed an integrated instrument panel system to meet ever-increasing industry targets for: Investment and piece-cost reduction; Mass/weight savings; Quality and performance improvements; Packaging and space availability; Government regulation levels; and Innovative technology. This system, developed through feedback with the DaimlerChrysler Corporation, combines the distinctive requirements of the instrument panel (IP) with the heater-ventilation-air-conditioning (HVAC) assembly. Implementing development disciplines such as benchmarking, brainstorming, and force ranking, a number of concepts were generated and evaluated. Using a current-production, small, multi-purpose vehicle environment, a mainstream concept was designed and engineered.

A model for calculating the trap pressure drop, particulate mass inside the trap and various particulate and trap properties was developed using the steady-state data and the theory developed by Konstandopoulos & Johnson, 1989. Changes were made with respect to the calculation of clean pressure drop, particulate layer porosity and the particulate layer permeability. This model was validated with the data obtained from the steady-state data run with different traps supplied by Corning Inc. The data were collected using the 1988 Cummins L-10 heavy-duty diesel engine using No.2 low sulfur diesel fuel. The three different traps were EX 80 (100 cell density), EX 80 (200 cell density) and EX 66 (100 cell density) all with a 229 mm diameter and 305 mm length. These traps were subjected to different particulate matter loadings at different speeds. The traps were not catalyzed.

During recent years the accident simulation program PCCRASH was developed, which allows to simulate the vehicles movement before, during and after the impact. As shown in several publications, the software allows to calculate the 3D movement of all involved vehicles. Within SAE 1999-01-0444 a new coupling interface of PC-CRASH and the software MADYMO, developed by TNO in the Netherlands was published. During last year's publication only few validation cases, mainly related to rear end impacts could be demonstrated. In the mean while several well documented tests have been performed to validate the performance of this model also in frontal and lateral collisions as well as rollovers. A special series of sled tests has been performed to study the movement of the passenger during and after the collision for various impact angles. These tests were performed on an active sled at various test speeds.

Offtracking is the term used to describe the difference in path radii between the leading and trailing axle of a vehicle as it maneuvers around a turn. This phenomenon probably has been observed from the time multi-axle vehicles first were constructed. As vehicles, particularly articulated trucks, have become larger and longer, and the urban environment has become more compact and crowded, practical safety concerns relating to offtracking have increased. The geometric design of streets and highways, and of parking lots and trucking yards, will be affected by the maximum offtracking of vehicles using those facilities. In some accident investigations, offtracking is a primary consideration. Much of present offtracking analysis is based upon a “zero-speed” assumption. In other words, the magnitude of offtracking is computed simply as a kinematic problem, with no dynamic effects considered.

Engineering Dynamics Corporation (EDC) recently updated the Human, Vehicle, Environment (HVE) software program to enable modeling of passenger cars and light trucks towing trailers. This paper reports on a comparison between the HVE EDSMAC4 collision module of the 3-dimensional computer simulation program and instrumented crash tests, in which one vehicle in each test was a pickup truck pulling a trailer. Use of the EDSMAC4 trailer model was found to provide better correlation between the simulation and test damage profiles, rest positions, vehicle trajectories, velocities, and Delta-V. It was also determined that the NHTSA-derived stiffness coefficients are sensitive to the impact configuration and depending on the impact configuration, it may be necessary to refine the coefficients according to the configuration.

A new algorithm for carrier removal, a key step in the Fourier transform method of fringe pattern analysis, is presented in this paper. The accuracy of frequency estimations is critical to carrier removal to avoid potential significant errors in the recovered phase. A new algorithm on Fourier transform and curve fitting technique is developed. To avoid an ill-conditioned result in solving the least-square problem, an orthogonal polynomial curve fitting algorithm is developed. A new system that combines projected grating moiré (PM) with shadow moiré (SM), recently designed and built with large dynamic range for both component level and board level warpage measurement for the reliability study of electronic packaging materials and structures, is presented and demonstrated.

Computer simulations are frequently used to analyze occupant kinematics in motor vehicle crashes, including what they collide with during the crash and the severity of these internal collisions. From study of such occupant simulations, it is then possible to infer how the actual human occupants may have been injured in a crash. When using a simulation to study how occupants react in a vehicle crash, a crash-pulse is usually required as input to the occupant simulation model. This crash-pulse is typically generated from a study of the vehicle motion and acceleration during the crash. There are several different methods for obtaining such a crash-pulse which are in common use. Each of these methods produces a different shape for the crash-pulse, even with identical velocity changes for the vehicle. The time duration, maximum acceleration, and general shape of the crash-pulse may influence the predicted motion of the occupants.

OEM's and car manufacturers suppliers have agreed to increase the electrical system operation voltage up to 42VDC -36VDC battery voltage- in order to save electricity and to enable near future vehicles, characterized by a high demand for power consumption, mainly because current mechanical operated systems - valves, air conditioning - are expected to be replaced by electrically powered systems. However, this transition towards a pure 42VDC network is going to be gradual, in a first step combining the current 14VDC -12VDC battery voltage -and the new 42VDC operating voltages, the so called “Dual Voltage architecture”. Electrical and Electronic Distribution Systems (EEDS) are the keystone of energy optimisation strategies that will successfully fulfil the new requirements and the following electrical systems' aspects must be taken into consideration for a Dual Voltage power network: protection, switching, conversion, control signal management and distribution.

A unified approach has been developed and applied to solder joint life prediction in this paper, which indicates a breakthrough for solder joint reliability simulation. It includes the material characterization of solder alloys, the testing of solder joint specimens, a unified viscoplastic constitutive framework with damage evolution, numerical algorithm development and implementation, and experimental validation. The emphasis of this report focuses on the algorithm development and experimental verification of proposed viscoplasticity with damage evolution.