Passenger Car Model Research Articles

Validation and Modeling of Transient Aerodynamic Loads Acting on a Simplified Passenger Car Model in Sinusoidal Motion

Validation and Modeling of Transient Aerodynamic Loads Acting on a Simplified Passenger Car Model in Sinusoidal Motion

Parameter Study for Child Injury Mitigation in Near-Side Impacts Through FE Simulations

Objective: The objective of this study is to investigate the effects of crash-related car parameters on head and chest injury measures for 3- and 12-year-old children in near-side impacts. Methods: The evaluation was made using a model of a complete passenger car that was impacted laterally by a barrier. The car model was validated in 2 crash conditions: the Insurance Institute for Highway Safety (IIHS) and the US New Car Assessment Program (NCAP) side impact tests. The Small Side Impact Dummy (SID-IIs) and the human body model 3 (HBM3) (Total HUman Model for Safety [THUMS] 3-year-old) finite element models were used for the parametric investigation (HBM3 on a booster). The car parameters were as follows: vehicle mass, side impact structure stiffness, a head air bag, a thorax–pelvis air bag, and a seat belt with pretensioner. The studied dependent variables were as follows: resultant head linear acceleration, resultant head rotational acceleration, chest viscous criterion, rib deflection, and relative velocity at head impact. The chest measurements were only considered for the SID-IIs. Results: The head air bag had the greatest effect on the head measurements for both of the occupant models. On average, it reduced the peak head linear acceleration by 54 g for the HBM3 and 78 g for the SID-IIs. The seat belt had the second greatest effect on the head measurements; the peak head linear accelerations were reduced on average by 39 g (HBM3) and 44 g (SID-IIs). The high stiffness side structure increased the SID-IIs’ head acceleration, whereas it had marginal effect on the HBM3. The vehicle mass had a marginal effect on SID-IIs’ head accelerations, whereas the lower vehicle mass caused 18 g higher head acceleration for HBM3 and the greatest rotational acceleration. The thorax–pelvis air bag, vehicle mass, and seat belt pretensioner affected the chest measurements the most. The presence of a thorax–pelvis air bag, high vehicle mass, and a seat belt pretensioner all reduced the chest viscous criterion (VC) and peak rib deflection in the SID-IIs. Conclusions: The head and thorax–pelvis air bags have the potential to reduce injury measurements for both the SID-IIs and the HBM3, provided that the air bag properties are designed to consider these occupant sizes also. The seat belt pretensioner is also effective, provided that the lateral translation of the torso is managed by other features. The importance of lateral movement management is greater the smaller the occupant is. Light vehicles require interior restraint systems of higher performance than heavy vehicles do to achieve the same level of injury measures for a given side structure.

Impact of Vehicle add-ons on Energy Consumption and Greenhouse Gas Emissions

The primary objective of this study is to determine the impact of vehicle add-ons on energy consumption and greenhouse gas emissions (mainly CO2) for commonly used fossil fuels in passenger car. Various commonly used vehicle add-ons (police siren, advertising sign, taxi sign and roof rack) and roof load (e.g., ladder and barrel) produce additional aerodynamic drag. To measure the aerodynamic drag produced by these add-ons a wind tunnel study was undertaken using a replica reduced scale model passenger car. The aerodynamic drag for different add-on configurations were measured for a range of vehicle operating speeds and yaw angles. The results show that the vehicle add-ons have notable impact on aerodynamic drag as they can generate 5% to 40% more aerodynamic drag depending on cross wind effects. The taxi sign has minimum impact and the advertising sign has highest impact on aerodynamic drag. Also roof load such as ladder and barrel can significantly increase the drag. The aerodynamic drag was related to a range of commonly used fuels e.g., petrol, diesel, compressed natural gas (CNG) and liquefying petroleum gas (LPG) consumption, and their relative CO2 gas emissions. The results indicate that for a given range, the emission of CO2 is the highest for the CNG due to its lowest energy density.

Effects on the Lumbar & Quadriceps Muscle Activities when Getting in and Out of RV · and Passenger Cars

Objective: The objective of this study is to compare muscle activity levels of the lumbar and rectus femoris muscle when entering and exiting RV and passenger vehicles. Background: Three varieties of RVs and two varieties of passenger vehicles were selected for this study. Method: Twenty individual(10 male and 10 female) in their twenties and thirties with no chronic back pain or any other illness participated in this study. Participants performed entering and exiting the three models of RVs and two models of passenger cars. Appropriate rest time was given to participants between entering and exiting each vehicle in order to recover from muscle fatigue while performing their tasks. Results: Results from this study show that muscle activity levels were highest for entering RVs and exiting passenger vehicles. There were no significant differences in muscle activity levels for left and right side muscles in regards to entering and exiting vehicles. Application: These results can be used to provide baseline information for reduce muscle fatigue when getting in and out of vehicles.

Sequencing Mixed Model Assembly Lines Based on Genetic Algorithm Optimization

Firstly, genetic algorithm optimization method was put forward to solve optimization problems of sequencing in actual mixed model passenger car factory assembly line. Then genetic algorithm optimization methods and procedures of mixed model total assembly line production sequencing were studied. Finally, according to the characteristics of the mixed production line, the least total waiting time of vehicle was set to complete assembly as a sequencing optimization objective, the AutoMod simulation software was used to balance the allocation of resources and optimize the sequence by way of genetic algorithm, and the optimal sequencing solution was obtained. After optimization and balance, the total waiting time of mixed model vehicles in complete assembly line was reduced by 69.5%, which improves production efficiency greatly. This also proves the effectiveness of genetic algorithm optimization.

Experimental analysis on a spark ignition petrol engine fuelled with LPG (liquefied petroleum gas)

The use of LPG (liquefied petroleum gas) as alternative fuel to petrol is common practise in spark ignition engines. While the main driving force to the use of LPG still remains the low cost for the end user, its favourable pollutant emissions, in particular carbon dioxide, will in the middle term probably increase interest in LPG as an IC engine fuel. In addition, there are both theoretical and technical reasons to consider LPG as an attractive fuel also in terms of engine performance. Despite the continuously increasing stock production of dual-fuel (petrol–LPG) passenger car models, doubts still exist about both real engine performance in LPG operation and the reliability of the dual-fuel feeding system. This paper deals with the theoretical advantages of using LPG as fuel for SI engines. Brake performance tests of a passenger car engine fed with petrol and LPG are analysed and compared. The stock engine has been equipped with a “third-generation” standard kit for dual-fuel operation. The performance reductions in LPG operation are discussed in both steady state and transient condition. The results of some modifications to the set-up of both the petrol and LPG metering devices, designed for a better justification of the measured performance, are also presented.

Railroad passenger car collision analysis and modifications for improved crashworthiness

In this study, crashworthiness assessment and suggestions for the modification of a railroad passenger car are presented. To assess the crashworthiness, collision of the railroad passenger car onto a rigid wall is simulated by using finite element (FE) methods. A full-length, detailed passenger car model is used in FE analyses. In order to validate the FE model, simulation results obtained for different types of static loading conditions in compliance with various scenarios defined in UIC CODE OR 577 are compared with experimental measurements before running collision analyses of the railroad passenger car. The good agreement between static tests and FE analyses results indicates that the FE model accurately represents the real structure. Following the FE model validation, analysis of the collision behaviour of the railroad passenger car consists of two stages. In the first stage, the crashworthiness of the initial concept design of the railroad passenger car is analysed. It was observed that local buckling takes place at various points, which prevents the desired progressive damage behaviour in the railroad car body. Having revealed the structural weaknesses, the initial design was modified and simulated again under the same conditions. Using size optimisation, thickness of some sheet metal components is changed in order to obtain the intended progressive damage behaviour. As a result of the modifications, the passenger car design with better crashworthiness properties was obtained, in which large plastic deformations occur around the collision side of the car while mainly elastic deformations occur in the car's body away from the bumpers.

Energy-absorbing FUPDs and their interactions with fronts of passenger cars

Structural and in-depth analyses of the crash accidents between heavy goods vehicles and passenger cars showed that the front underrun protective device (FUPD), obeying the Economic Commission for Europe Regulation No. 93, is not sufficient to protect the passenger cars from overriding by heavy goods vehicles in all expected traffic situations. This is based on the expectation that an FUPD will mitigate the severity of these accidents. The unpredictable behaviour of a car during frontal collisions has been identified as a central issue to resolve for FUPD development and testing. On the basis of the findings from the in-depth accident analysis, a simulation matrix was designed and simulations between a passenger car model and a model of FUPD with energy-absorbing elements were run. The goal of the simulations was to understand the theoretical possibilities for energy-absorbing FUPDs and identify some of the critical structural requirements needed to improve frontal crash protection. An analysis of the simulation results showed that a properly activated FUPD with energy-absorbing elements can decrease the severity of the crash by absorbing more than 30% of the total kinetic energy. It was found that the force needed to activate the deformation of FUPD energy-absorbing elements can be used to improve the deformation mode of the car front structure in such a way as to decrease the crash severity.

Optimisation of vehicle side interior panels for occupant safety in side impact

In a car side crash, the interior panels of the door and B-pillar could have a direct contact with the occupant of a struck car, which is a risk for occupant chest injuries. Therefore, the objective of the study is to enhance car safety performance for occupant chest protection by optimising the interior panel's properties and design parameters. A production passenger car finite-element model was developed and used to analyse the interior panels design for occupant protection. Prescribed structural motion technology was employed to reduce the computation time. The elastic modulus and thickness of the interior panels of the door and B-pillar are considered as design parameters. An optimisation of the interior panels was carried out by using the response surface methodology with quadratic functions. The efficiency of the optimisation was identified by reducing the risk of thorax injury by 25%.

Acceleration of Ray-Based Radar Cross Section Predictions Using Monostatic-Bistatic Equivalence

An approach is presented to simulate the monostatic scattering properties of complex shaped realistic objects in a very efficient way. To achieve this, the calculation of the radar cross section (RCS) in the high frequency regime based on the well known shooting and bouncing rays (SBR) technique is considerably accelerated by the use of the monostatic bistatic equivalence principle. Instead of performing independent simulations for all required aspect angles, the concept is based on the idea of additionally exploiting bistatic information for some neighboring aspect angles. This information is obtained relatively cheaply during the SBR process and it can be favorably exploited under certain conditions, mainly that the bistatic angle is small and the object is sufficiently smooth. In this case, the results of the geometrical ray tracing, which consumes a large part of the computational resources for complex shaped objects is reused multiple times with only low additional computational resources. The basic principles and benefits of the methodology are discussed as well as its limitations and drawbacks. Different generic simulation examples are used to show the general applicability of the method and to examine the degradation of the results depending on the applied bistatic angle. Based on these experiences, a passenger car model is simulated at 10 GHz and a considerable reduction of the computational effort by a factor of 32 is estimated for the complete multiaspect simulation problem.

Evaluation of a plug‐in hybrid electric vehicle considering power generation best mix

AbstractIn the transport section, it is necessary to reduce the amount of CO2 emissions and oil dependence. Bio fuels and fuel cell vehicle (FCV), electric vehicle (EV) and plug‐in hybrid electric vehicle (PHEV) are expected to reduce CO2 emissions and oil dependence. We focus on PHEV. PHEV can reduce total energy consumption because of its high efficiency and can run with both oil and electricity. Introduction of PHEV reduces oil consumption, but it also increases electricity demands. Therefore, we must evaluate PHEV's CO2 reduction potential, not only in the transport section but also in the power grid section. To take into account the distribution of the daily travel distance is also very important. All energy charged in the PHEV's battery cannot always be used. That influences the evaluation.We formulate the total model that combines passenger car model and power utility grid model, and we also consider the distribution of the daily travel distance. With this model, we show the battery cost per kWh at which PHEV begins to be introduced and oil dependence in the passenger car section is to be reduced to 80%. We also show PHEV's CO2 reduction potentials and effects on the power supply system. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(2): 12–22, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20920

A new criterion for assessment of train derailment risk

A new criterion for prediction of train derailment is presented in this article. A three-degrees-of-freedom (3 DOF) wheelset model is used to identify the main dynamic parameters that affect wheelset derailment. Using these parameters and conventional definition of derailment coefficient, a new criterion for prediction of wheelset derailment is introduced. The proposed criterion, in addition to providing the required precision in prediction of wheel set derailment, requires measurements that are easy to perform. To evaluate the capability of the new criterion in prediction of derailment, a full wagon model with 48 DOF moving on a track with different random irregularities was used. The track is assumed to be mounted on a viscoelastic foundation. The wagon model is a three-dimensional, non-linear model of a train passenger car. The model includes non-linear elements for primary and secondary suspension systems. Friction and slack between elements, the centre pivot with kinematics constraints, forces between pads, and bolster are also included in this model. The motion of the wagon on tangent and curved tracks is simulated for different travel speeds. Derailment coefficient and a new derailment criterion are used to investigate the possibility of wheelset derailment in each case. The study shows that the new criterion can very well predict wheelset derailment and can duplicate the predictions by conventional derailment coefficient ( Y/ Q).

Product variety: an auto industry analysis and a benchmarking study

PurposeThe purpose of this paper is to develop a product variety multi‐market study in the auto industry and to conduct a benchmarking analysis of the practical findings against the theoretical ones obtained in a European Community Research Project (Intelligent Logistics for Innovative Product Technologies – ILIPT) that aims to rethink the automotive supply chain.Design/methodology/approachThe authors conduct an exploratory research including an empirical multi‐market study, which embraces many significant passenger car models from a global vehicle manufacturer in relevant automotive markets. To provide a rich dataset, the authors utilize a combination of data collection techniques including interviews, contextual performance data and a detailed analysis of product offerings available from the vehicle manufacturer's regional web sites. This paper also shares the experience of a European Community Research Project benchmarking the results for the automobile industry.FindingsIn this paper, product variety in the auto industry is classified into four general categories. The empirical results suggest that the platform (most aggregated form of variety) follows the same logic worldwide while all the other product variety categories (in particular variants) are restricted in emerging markets and very refined in Europe. The benchmarking shows that the European variety offered exceeds the “appropriate” level of variety considered best in class by the ILIPT project while the emerging countries variety offered is below this level. This fact points to space for improvement in the product variety management of both supply chains.Originality/valueThis is a valuable empirical research study that examines the current behaviour of the auto product variety in significant markets and gives an overview where the variety is created world wide. A benchmarking analysis is also offered, which gives an idea of how far vehicle manufacturers are in terms of providing the “appropriate” level of variety.

Interior sound field refinement of a passenger car using modified panel acoustic contribution analysis

Panel acoustic contribution analysis (PACA) is a practical engineering tool for the reduction of interior structure-borne noise in passenger cars. In this study, the current PACA method has been improved for sound field refinement of the entire interior. Two new parameters, the “acoustic contribution sum” and the “total sound field contribution”, are introduced to analyze the interior sound field characterized with multiple field points and sound pressure peaks, and to evaluate the integrated acoustic contributions of auto body panels. In addition, a systematic methodology for automotive interior sound field refinement is also proposed on the basis of the modified PACA method. An example of a passenger car model demonstrates the application of the sound-field-refinement methodology and shows the advantage of using damping layers at optimum locations on the auto body. The example also shows that the modified PACA method has practical significance for refining the interior sound field and decreasing added mass in accord with the trend towards lightweight auto bodies.

The application of power-based transfer path analysis to passenger car structure-borne noise

Structure-borne noise in a passenger car is usually transmitted through multiple and/or multi-dimensional paths. Therefore, identification and control of these transfer paths are effective measures for noise reduction. A power-based transfer path analysis methodology is proposed for this purpose. First, the power flow of each transfer path is estimated with an equivalent-uncoupled-system method based on linear network theory and the Thevenin equivalent theorem. Next, the correlation between the power flow of each transfer path and the sound pressure in the passenger compartment is established; then the contribution of each transfer path is ranked; meanwhile the dominant paths and their key parameters are identified through the equations of power flow calculation. Finally, these key parameters can be analysed and then improved to reduce the structure-borne noise. An illustration of this methodology is given with a passenger car model containing a power plant, three mounts, a compliant car body, and an enclosed acoustic cavity. It is demonstrated that the methodology is effective to analyse and control the structure-borne noise transfer paths.

Two tracking control problems applied to damping nonlinear vehicle vibrations

A global control strategy of linear and nonlinear control methods is developed for application to the design of hydraulic suspensions in ground vehicles. A nonlinear, three-dimensional passenger car model of 7-dof is used to investigate vehicle ride capabilities with hydraulic actuators employed as active suspension elements. The design procedure starts with the application of an optimal control method of multiple-structure constraints to the optimization of suspension performance in the absence of system nonlinearities. Hence, the strong nonlinearity of hydraulic actuators is considered, and the optimal linear solutions are implemented as reference values to be asymptotically tracked. Two contrasting nonlinear control methods, called input–output linearization and sliding mode control, are used to achieve the asymptotic tracking problem in the presence of Coulomb friction and model uncertainties. Digital simulation shows that the input–output controller is effective as long as the suspension is frictionless and the system knowledge is perfect. Conversely, the robustness of the sliding mode controller makes it capable of providing good tracking even in cases of model uncertainty. The whole design procedure is demonstrated with numerical examples showing its significance. The procedure also allows for the simultaneous design of optimal passive suspension elements to be mechanized in parallel with the hydraulic actuators in order to increase suspension reliability.

Superior Industries International, Inc.

AbstractAutomotive (MIC: 15.1 SIC: 3714 NAIC: 336399)Superior Industries International is primarily engaged in the design and manufacture of aluminum road wheels for sale to original equipment manufacturers. In addition, Co. supplies cast and forged aluminum wheels to the worldwide automobile and light truck manufacturers, with wheel manufacturing operations in the U.S., Mexico and Hungary. As of Dec 31 2006, Co. supplied cast and forged aluminum wheels and components for many North American model passenger cars and light trucks, including, but not limited to, Ford's F‐150 and Mustang, General Motors' GMT800 trucks, Chevrolet Malibu and Corvette, and DaimlerChrysler's Jeep Grand Cherokee.

系統電源構成を考慮したプラグインハイブリッド自動車の導入評価

In transport section, it is necessary to reduce amount of CO2 emissions and Oil dependence. Bio fuels and Fuel Cell Vehicle (FCV), Electric Vehicle (EV) and Plug-in Hybrid Electric Vehicle (PHEV) are expected to reduce CO2 emissions and Oil dependence. We focus on PHEV. PHEV can reduce total energy Consumptions because of its high efficiency and can run with both oil and electricity. Introduction of PHEV reduces oil consumptions, however it also increases electricity demands. Therefore we must evaluate PHEV's CO2 reduction potential, not only in transport section but also in power grid section. To take into account of the distribution of the daily travel distance is also very important. All energy charged in the PHEV's battery cannot always be used. That influences the evaluation.We formulate the total model that combines passenger car model and power utility grid model, and we also consider the distribution of the daily travel distance. With this model, we show the battery cost per kWh at which PHEV begins to be introduced and oil dependence in passenger car section is to be reduced to 80%. We also show PHEV's CO2 reduction potentials and effects on the power supply system.

Superior Industries International, Inc.

AbstractAutomotive (MIC: 15.1 SIC: 3714 NAIC: 336399)Superior Industries International is primarily engaged in the design and manufacture of aluminum road wheels for sale to original equipment manufacturers (OEM). Co. supplies cast and forged aluminum wheels to the worldwide automobile and light truck manufacturers, with wheel manufacturing operations in the U.S., Mexico and Hungary. As of Dec 31 2006, Co. supplied cast and forged aluminum wheels and components for many North American model passenger cars and light trucks, including Ford's F‐150 and Mustang, General Motors' GMT800 trucks, Chevrolet Malibu and Corvette, and DaimlerChrysler's Jeep Grand Cherokee.

Superior Industries International, Inc.

AbstractAutomotive (MIC: 15.1 SIC: 3714 NAIC: 336399)Superior Industries International is primarily engaged in the design and manufacture of aluminum road wheels for sale to original equipment manufacturers (OEM). Co. supplies cast and forged aluminum wheels to the worldwide automobile and light truck manufacturers, with wheel manufacturing operations in the U.S., Mexico and Hungary. As of Dec 31 2006, Co. supplied cast and forged aluminum wheels and components for many North American model passenger cars and light trucks, including Ford's F‐150 and Mustang, General Motors' GMT800 trucks, Chevrolet Malibu and Corvette, and DaimlerChrysler's Jeep Grand Cherokee.