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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.

A dynamic computer model of automotive air conditioning systems was developed. The model uses simulation software for the coding of 1-D heat transfer, thermodynamics, fluid flow, and control valves. The same software is used to model 3-D solid dynamics associated with mechanical mechanisms of the compressor. The dynamics of the entire AC system is thus simulated within the same software environment. The results will show the models potential applications in component and system design, calibration and control.

Virtual design validation of an air induction system (AIS) requires a proper finite element (FE) assembly model for various simulation based design tasks. The effect of the urethane air filter seal within an AIS assembly, however, still poses a technical challenge to the modeling of structural dynamic behaviors of the AIS product. In this paper, a filter seal model and its modeling approach for AIS assemblies are introduced, by utilizing the feature finite elements and empiric test data. A bushing element is used to model the unique nonlinear stiffness and damping properties of the urethane seal, as a function of seal orientation, preloading, temperature and excitation frequency, which are quantified based on the test data and empiric formula. Point mobility is used to character dynamic behaviors of an AIS structure under given loadings, as a transfer function in frequency domain.

Accurate evaluation of vehicles' transient total power requirement helps achieving further improvements in vehicle fuel efficiency. When operated, the air-conditioning (A/C) system is the largest auxiliary load on a vehicle, therefore accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation models, such as "Autonomie," have been used by OEMs to evaluate vehicles' energy performance. However, the load from the A/C system on the engine or on the energy storage system has not always been modeled in sufficient detail. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software MATLAB/Simulink® is frequently used by vehicle controls engineers to develop new and more efficient vehicle energy system controls.

Generalized predictive control (GPC) is a discrete time control strategy proposed by Clark et al [1]. The controller tries to predict the future output of a system or plant and then takes control action at present time based on future output error. Such a predictive control algorithm is presented in this paper for yaw stability management of an automobile. Most of the existing literature on the yaw stability management systems lacks the insight into the yaw rate error growth when the automobile is in a understeer or oversteer condition on a low friction coefficient surface in a handling maneuver. Simulation results show that the predictive feature of the proposed controller provides an effective way to control the yaw stability of a vehicle.

Generalized predictive control (GPC) is a discrete time control strategy proposed by Clark et al [1]. The controller tries to predict the future output of a system or plant and then takes control action at present time based on future output error. Such a predictive control algorithm is presented in this paper for deceleration slip regulation in an automobile. Most of the existing literature on the anti-lock brake control systems lacks the effectiveness of the wheel lockup prevention when the automobile is in a skid condition (in a low friction coefficient surface with panic braking situation). Simulation results show that the predictive feature of the proposed controller provides an effective way to prevent wheel lock-up in a braking event.

The traditional method of engine knock detection is to compare the knock intensity with a predetermined threshold. The calibration of this threshold is complex and difficult. A statistical knock detection method is proposed in this paper to reduce the effort of calibration. This method dynamically calculates the knock threshold to determine the knock event. Theoretically, this method will not only adapt to different fuels but also cope with engine aging and engine-to-engine variation without re-calibration. This method is demonstrated by modeling and evaluation using real-time engine dynamometer test data.

Application of Ultra Thin Wall (UTW) ceramic substrates in the catalytic converter system requires the canner and component manufacturers to better understand the root cause and physics behind substrate breakage during the canning process. For this purpose, a ceramic substrate strength study for shoebox design has been conducted within Visteon Corporation. Computer Numerical Control (CNC) machined top and bottom fixtures, with identical inner surfaces as shoebox converter upper and lower shells, were used to crush mat wrapped substrates. Thin film pressure sensor technology enables the recording of substrate surface pressure during the compression process. Shell rib, washcoat, canning speed and cell density effects on substrate failure have been experimentally investigated. The development of a mathematical model helps to identify a better indicator to evaluate the substrate strength in the canning process and establish the strength for uncoated & coated substrates.

Experimental correlation is essential in the development of analytical simulation models. A methodology for correlating an All-Wheel Drive (AWD) minivan, created with ADAMS/Pre is presented in this paper. The paper is developed in three parts. Presented first are detailed component and system level, static and dynamic tests, including tire tests that were performed for inputs to the model. Then, the static correlation of the model, in particular, the front and rear suspension kinematics and compliance correlation are presented. Finally the dynamic correlation of the model, for the constant radius test and the swept steer test, is discussed. The paper concludes with some observations on AWD modeling.

The process for accurately estimating product reliability early in the development process can be a difficult and costly task. Traditional methods like Reliability Prediction Models and Life Testing Strategies yield beneficial results when relative information is known about the product that is to be analyzed. When there is minimal information known (prior failure rates…) such a new concept design these above reliability methods have limitations. For these cases a Virtual Testing Strategies have proven to yield valuable results. This paper will demonstrate a reliability analysis procedure for a new automotive concept design. This analysis procedure composes of a mathematical model, model validation, parameter diagram, design of experiment (DOE), response surface, and optimization.

Reliable prediction of the radiated noise due to the air pressure pulsation inside air-intake manifolds (AIM) is of significant interest in the automotive industry. A practical methodology to model plastic AIMs and a prediction process to compute the radiated noise are presented in this paper. The measured pressure at the engine inlet valve of an AIM is applied as excitation on an acoustic boundary element model of the AIM in order to perform a frequency response analysis. The measured air pressure pulsation is obtained in the crank-angle domain. This pressure is read into MATLAB and transformed into the frequency domain using the fast Fourier transform. The normal modes of the structure are computed in ABAQUS and a coupled analysis in SYSNOISE is launched to couple the boundary element model and the finite element model of the structure. The computed surface vibration constitutes the excitation for an acoustic uncoupled boundary element analysis.

Traditionally fog lamps use halogen filament light sources. With the emergence of high brightness white LEDs, it is now possible to develop automotive forward lighting systems with LED light sources. Six LEDs are shown to be sufficient for the implementation of a European fog lamp using a faceted reflector optical approach. Each reflector together with the LED light source forms a modular element. The optical parameters of two different lamp designs are compared and correlation between the simulation and prototype measurements is shown. Further, additional forward lighting functions can be implemented through the use of additional elements.

This paper discusses our experiences on the implementation and benefits of using the Hardware-In-the-Loop (HIL) systems for Powertrain control system software verification and validation. The Visteon HIL system integrated with several off-the-shelf diagnostics and calibration tools is briefly explained. Further, discussions on test automation sequence control and failure insertion are outlined The capabilities and advantages of using HIL for unit level software testing, open loop and closed-loop system testing, fault insertion and test automation are described. HIL also facilitates Software and Hardware Interface validation testing with low-level driver and platform software. This paper attempts to show the experiences with and capabilities of these HIL systems.

This paper presents an assessment of competing algorithms for normalizing volume levels between tracks and/or sources in an automotive infotainment system. Portable media players such as smartphones and iPod® devices are extremely popular for listening to music collections or streaming content from the Internet. The lack of normalization is a source of dissatisfaction if the user experiences significant changes in audio level between tracks. Several commercially available algorithms exist to solve this problem. This research includes a double-blind listening test comparing an audio sample processed with the different leveling algorithms to an unprocessed reference. The listener preference rating is recorded and results indicate which algorithm is preferred.

Occupant head impact simulations on automotive instrument panels (IP) are routinely performed as part of an integrated design process during the course of IP development. Based on the requirements (F/CMVSS, ECE), head impact zones on the IP are first established, which are then used to determine the various “hit” locations to be tested/analyzed. Once critical impact locations are identified, CAE simulations performed which is a repetitive process that involves computing impact angles, positioning the rigid head form with an assigned initial velocity and defining suitable contacts within the finite element model. A commercially available CAE process automation tool was used to automate these steps and generate a head impact simulation model. Once the input model is checked for errors by the automated process, it can be submitted to a solver without any user intervention for analysis and report generation.

Up to date, computer aided engineering (CAE) has been used in improvement of design quality and reduction of cost and delivery time. Although it has been widely accepted as a standard product development tool by the engineering community, CAE still faces many challenges in improving simulation process efficiency through process integration and automation, and simulation accuracy by analytical model/physical testing correlation. CAE engineers are constantly improving the accuracy of their analytical models through test correlation to deliver higher confidence for their analysis result. Although laboratory testing has provided an effective way to accelerate product development, analytical simulation of the lab test has been used frequently to further reduce the development cost and time throughout many industries. This paper presents a case study of CAE correlation of a finite element (FE) model of an automotive beam axle assembly in a laboratory test environment.

A practical and low cost Blind Spot Monitoring system is proposed. By using a single camera, the range and azimuth position of a vehicle in a blind spot are measured. The algorithm is based on the proposed RWA (Range Window Algorithm). The camera is installed on the door mirror and monitoring the side and rear of the host vehicle. The algorithm processes the image and identifies range and azimuth angle of the vehicle in the adjacent lane. This algorithm is applied to real situations. The 388 images including several kinds of vehicles are analyzed. The detection rate is 86% and the range accuracy is 1.6[m]. The maximum detection range is about 30[m].

Computational Fluid Dynamics (CFD) is an integral part of product development at Visteon Climate Systems with a validated set of CFD tools for airflow and thermal management processes. As we increasingly build CAE capabilities to design not only thermal comfort, but quiet systems, developing noise prediction capabilities becomes a high priority. Two Broadband Noise Source (BNS) models will be presented, namely Proudman's model for quadrupole source and Curle's boundary layer model for dipole source. Both models are derived from Lighthill's acoustic analogy which is based on the Navier-Stokes equations. BNS models provide aeroacoustic tools that are effective in screening air handling systems with higher noise levels and identifying components or surfaces that generate most of the noise, hence providing opportunities for early design changes. In this paper, BNS models were used as aeroacoustic design tools to redesign an automotive HVAC center duct with high levels of NVH.

Welding is one of the most commonly used fabrication method in various automotive applications. Welding is a metallurgical fusion process in which parts or work pieces to be joined are heated above their melting temperature and then solidified. Some of the effects of the welding include residual stresses and Heat Affected Zone (HAZ). A methodology is proposed to study the welding process using the commercial finite element software, ABAQUS. Non linear transient heat transfer analysis is used. Effects of heat energy input rate and heat input time on residual stresses and HAZ are determined.

A coupled vibration and pressure loading procedure has been developed to perform a CAE virtual test for engine air intake manifolds. The CAE virtual test simulates the same physical test configuration and environments, such as the base acceleration vibration excitation and pressure pulsation loads, as well as temperature conditions, for design validation (DV) test of air intake manifolds. The original vibration and pressure load data, measured with respect to the engine speed rpm, are first converted to their respective vibration and pressure power spectrum density (PSD) profiles in frequency domain, based on the duty cycle specification. The final accelerated vibration excitation and pressure PSD load profiles for design validation are derived based on the key life test (KLT) duration and reliability requirements, using the equivalent fatigue damage technique.