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Viewing 1 to 30 of 7617
2010-10-25
Journal Article
2010-01-2104
Ulf Aronsson, Clément Chartier, Öivind Andersson, Bengt Johansson, Johan Sjöholm, Rikard Wellander, Mattias Richter, Marcus Alden, Paul C. Miles
The soot distribution as function of ambient O₂ mole fraction in a heavy-duty diesel engine was investigated at low load (6 bar IMEP) with laser-induced incandescence (LII) and natural luminosity. A Multi-YAG laser system was utilized to create time-resolved LII using 8 laser pulses with a spacing of one CAD with detection on an 8-chip framing camera. It is well known that the engine-out smoke level increases with decreasing oxygen fraction up to a certain level where it starts to decrease again. For the studied case the peak occurred at an O₂ fraction of 11.4%. When the oxygen fraction was decreased successively from 21% to 9%, the initial soot formation moved downstream in the jet. At the lower oxygen fractions, below 12%, no soot was formed until after the wall interaction. At oxygen fractions below 11% the first evidence of soot is in the recirculation zone between two adjacent jets.
2010-10-05
Technical Paper
2010-01-2033
Gergis W. William
Currently, the chassis assembly contributes about 73 percent of the overall weight of a 14.63 m long haul trailer. This paper presents alternative design concepts for the structural floor of a van trailer utilizing sandwich panels with various material and geometric characteristics of the core layer in order to reduce its weight significantly below that of the current design configuration. The main objective of the new designs is to achieve optimal tradeoffs between the overall structural weight and the flexural stiffness of the floor. Various preliminary design concepts of the core designs were compared on the basis of a single section of the core structure. Six different designs were analyzed by weight, maximum displacement and maximum stress under bending and torsion loads. Each concept was kept uniform by length, thickness, loading and boundary conditions. Each design concept was examined through testing of scaled model for floor assemblies.
2010-10-05
Technical Paper
2010-01-2039
Stargel Doane, Drew Landman, Richard M. Wood
A computer simulation was developed to investigate the effect of wind on test track estimation of heavy truck fuel efficiency. Monte Carlo simulations were run for various wind conditions, both with and without gusts, and for two different vehicle aerodynamic configurations. The vehicle configurations chosen for this study are representative of typical Class 8 tractor trailers and use wind tunnel measured drag polars for performance computations. The baseline (control) case is representative of a modern streamlined tractor and conventional trailer. The comparison (test) case is the baseline case with the addition of a trailer drag reduction device (trailer skirt). The integrated drag coefficient, overall required power, total fuel consumption, and average rate of fuel consumption were calculated for a heavy truck on an oval test track to show the effect of wind on test results.
2010-10-05
Technical Paper
2010-01-2040
Mathew Heinecke, Jeremy Beedy, Kevin Horrigan, Raja Sengupta
The importance of fuel economy and emission standards has increased rapidly with high fuel costs and new environmental regulations. This requires analysis techniques capable of designing the next generation long-haul truck to improve both fuel efficiency and cooling. In particular, it is important to have a predictive design tool to assess how exterior design changes impact aerodynamic performance. This study evaluates the use of a Lattice Boltzmann based numerical simulation and the National Research Council (NRC) Canada's wind tunnel to assess aerodynamic drag on a production Volvo VNL tractor-trailer combination. Comparisons are made between the wind tunnel and simulation to understand the influence of wind tunnel conditions on truck aerodynamic performance. The production VNL testing includes a full range of yaw angles to demonstrate the influence of cross wind on aerodynamic drag.
2010-10-05
Technical Paper
2010-01-2036
Gergis W. William
Recent advances in Metal Matrix Composites have made them ready for transition to large-volume production and commercialization. Such new materials seem to allow the fabrication of higher quality parts at less than 50 percent of the weight as compared to steel. The increasing requirements of weight savings and extended durability motivated the potential application of MMC technology into the heavy vehicle market. However, significant technical barriers such as joining are likely to hinder the broad applications of MMC materials in heavy vehicles. The focus of this paper is to examine the feasibility of manufacturing and the behavior of bolted joint connections made from aluminum matrix reinforced with Silicon Carbide (SiC) particles. Two reinforcement ratios: 20% and 45% were considered in this study. The first part of the paper concentrates on experimental evaluation of bolted MMC joints.
2010-10-05
Technical Paper
2010-01-2025
Abhijeet Pingale, Deepak Vani
In traditional manufacturing processes a lot of material is wasted in hidden ways. These can be identified through Lean Manufacturing systems. It is proven that the Lean Approach eliminates waste and improves value. This reduces excessive investment in working capital and improves Return on Invested Capital (RoIC). As a result, the shareholder's value is maximized through simultaneously reducing costs and increasing capital efficiency. To demonstrate this we analyzed the production process of the Upper Output Shaft , a key component in a typical drive train assembly like a Four Wheel Drive transfer case, used in a pickup truck or SUV. Value Stream Mapping (VSM) is used to identify and reduce non value-added activities.
2010-10-05
Technical Paper
2010-01-2031
Robert Hupfer, Georg Habbel
The heavy-duty truck industry has adopted various methods and technologies to provide comfort in sleeper cabins during rest periods. For heating a sleeper cabin the fuel-operated heating technology has been used already industry wide, due to performance, ecological, and economical reasons. The same criteria apply to the comfort requirements in the summer or in warmer climate. One of the most common methods is still the idling of the main truck engine. While engine idling increases both fuel consumption and emissions, it is also having a negative effect on the engine and exhaust system maintenance, especially with the latest changes of the emission regulation and the application of active and passive Diesel Particulate Filter (DPF) regeneration strategies.
2010-10-05
Technical Paper
2010-01-2011
Carsten John
Geometric product representations are of gaining importance in product manufacturing industries. Several case studies yield that the utilization of three-dimensional digital product data in the product development chain has given many manufacturing companies a big advantage in business competition. The field of application for 3D technology is versatile and its further implementation still proceeds along product delivery processes. Leveraging 3D graphics in service information creation processes like the creation of manual illustrations or service instruction imagery is currently a big topic at many companies. E. g. the utilization of animated 3D product representations for explanation of service tasks becomes possible due to the recent advances in computer hardware more and more popular.
2010-10-05
Technical Paper
2010-01-2010
Josko Petric
Recent innovative drives in hydraulics could introduce very competitive hybrid hydraulic vehicles (HHV). These drives has been considered and analyzed only in the serial HHV architecture. The series-parallel transmission architecture, also called power-split or e-CVT is highlighted as the most popular concept for full (strong) hybrid electric vehicles (HEV). The examples are one-mode power-split in Toyota Prius and two-mode (compound) power-split in GM-Allison EVT. Ambitions to make the hybrid hydraulic power trains better and more efficient would certainly require deeper analysis of more complex power-split (series-parallel) HHV transmission structures and related optimal controls. This paper presents bond graph based mathematical model of kinematics of a one-mode and a two-mode power-split hybrid hydraulic vehicle transmissions which are based on their hybrid electrical counterpart.
2010-10-05
Technical Paper
2010-01-2015
Saurabh Singh, Narayan Jadhav, Kamaljeet Nandkeolyar, Shirish Pandav, Pankaj Sali
The automotive sector is going through a phase of stiff competition among various Original Equipment Manufacturers for increasing their profitability while ensuring highest levels of customer satisfaction. The biggest challenge for such companies lies in minimizing their overall cost involving investments in Research and Development, manufacturing, after sales service and warranty costs. Higher warranty costs not only affect the net profit but in turn it also affects the brand image of the company to a large extent in the long run. An effort is made here to target such warranty costs due to frequent tail pinion and hub seal leakages on single reduction/hub reduction axles of Heavy Commercial Vehicles in the field. A preliminary study involving the severity analysis of such failures is followed by a step by step investigation of these failures.
2010-10-05
Technical Paper
2010-01-2012
Arnold Taube, Matthew Cappel, Vincent Boens
Light-weight, tessellated surface models are increasingly used in marketing websites and electronic documents as well as in electronic training materials and service information documents. While these models are effective in developing consumer interest and communicating information, without implementing adequate Intellectual Property Protection (IPP) they also provide valuable geometry to miscreants wanting to reverse engineer a product and/or its component parts. Geometry Distortion is an excellent component of a layered IPP Plan for implementation when publishing 3-D models. However, how much distortion is needed to provide adequate IPP? Too much distortion detracts from their appearance while too little does not sufficiently complicate reverse engineering analysis. This paper describes a practical process for determining rational geometry distortion values that provide adequate IPP.
2011-04-12
Technical Paper
2011-01-0269
Adam Bryant, Joseph Beno, Damon Weeks
Battlefield reconnaissance is an integral part of today's integrated battlefield management system. Current reconnaissance technology typically requires land based vehicle systems to observe while stationary or, at best, significantly limits travel speeds while collecting data. By combining current Canadian Light Armored Vehicle based reconnaissance systems with the Center for Electromechanics (CEM) electronically controlled active Electromechanical Suspension System (EMS), opportunities exist to substantially increase cross-country speeds at which useful reconnaissance data may be collected. This report documents a study performed by The University of Texas Center for Electromechanics with funding from L3-ES to use existing modeling and simulation tools to explore potential benefits provided by EMS for reconnaissance on the move.
2011-04-12
Technical Paper
2011-01-0333
Yousef Jeihouni, Stefan Pischinger, Ludger Ruhkamp, Thomas Koerfer
Fuel properties are always considered as one of the main factors to diesel engines concerning performance and emission discussions. There are still challenges for researchers to identify the most correlating and non-correlating fuel properties and their effects on engine behavior. Statistical analyses have been applied in this study to derive the most un-correlating properties. In parallel, sensitivity analysis was performed for the fuel properties as well as to the emission and performance of the engine. On one hand, two different analyses were implemented; one with consideration of both, non-aromatic and aromatic fuels, and the other were performed separately for each individual fuel group. The results offer a different influence on each type of analysis. Finally, by considering both methods, most common correlating and non-correlating properties have been derived.
2011-04-12
Technical Paper
2011-01-0335
Lucas Murphy, David Rothamer
The effects of jet fuel properties on compression ignition engine operation were investigated under high-load conditions for jet fuels with varying cetane number. A single-cylinder oil-test engine (SCOTE) with 2.44 L displacement was used to test a baseline #2 diesel fuel with a cetane number of 43, a Jet-A fuel with a cetane number of 47, and two mixtures of Jet-A and a Fishcer-Tropsch JP-8 with cetane numbers of 36 and 42, respectively. The engine was operated under high-load conditions corresponding to traditional diesel combustion, using a single injection of fuel near TDC. The fuels were tested using two different intake camshafts with closing times of -143 and -85 CAD BTDC. Injection timing sweeps were performed over a range of injection timings near TDC for each camshaft. The apparent net heat release rate (AHRR) data showed an increase in the premixed burn magnitude as cetane number decreased in agreement with previous work.
2011-04-12
Technical Paper
2011-01-0266
J.Y. Wong
With growing globalization of the economy, to gain a competitive edge in world markets shortening the product development cycle is crucial. Virtual product development is, therefore, being actively pursued in the off-road vehicle industry. To implement this process successfully, the development of comprehensive and realistic computer-aided methods for performance and design evaluation of off-road vehicles is of vital importance. To be useful to the engineer in industry for the development and design of new products, the computer-aided methods should take into account all major vehicle design parameters and pertinent terrain characteristics. They should be based on the understanding of the physical nature and the mechanics of vehicle-terrain interaction. Their capabilities should be substantiated by test data.
2011-04-12
Journal Article
2011-01-0437
Mina M.S. Kaldas, Roman Henze, Ferit Küçükay
Due to the importance of the fast transportation under every circumstance, the transportation process may require a high speed heavy vehicle from time to time, which may turn the transportation process more unsafe. Due to that fact the truck safety during braking and the ride comfort during long distance travelling with high speeds should be improved. Therefore, the aim of this work is to develop a control system which combines the suspension and braking systems. The control system consists of three controllers; the first one for the active suspension system of the truck body and cab, the second one for the ABS and, the third for the integrated control system between the active suspension system and the ABS. The control strategy is also separated into two strategies.
2011-04-12
Journal Article
2011-01-0459
Chee Yap, Ronald Stapleton, Ronald Smolinski
The drive to incorporate renewable resources continues to gain momentum within the automotive industry. FXI has developed a grade of low (1.7 pcf) density slabstock foam which uses a natural oil polyol in place of a petroleum-based polyol. This foam grade, trademarked GreenBlend\St, has been developed specifically to produce foam-fabric/vinyl laminates for automotive seating, and interior trim applications such as headrests, armrests, visors and door panels. This new foam grade satisfies all of the OEM specifications for physical properties, including fogging and flammability, and yields satisfactory bond strengths when flame-laminated to cover stock. It is also s cost competitive technology compared to conventional slabstock foam using petroleum-based polyols.
2011-04-12
Technical Paper
2011-01-0399
Andre Ferrarese, Jason Bieneman, David J. Domanchuk, Thomas Smith, Thomas Stong, Peter Einberger
Changing emission legislation limits are challenging the engine developers in many aspects. Requirement to improve combustion and engine efficiency have resulted in increased loads and higher levels of abrasive particles within the engine environment. Concerning piston rings and piston ring grooves, such engine modifications are leading to critical tribological conditions and side wear is becoming a key issue in the design of these components. Historically one of the most common forms of side wear protection on piston rings has been chromium plate. This solution has limitations on durability (low thickness) and on topography (rough surfaces). In response to these limitations, nitrided stainless steel top rings have been used to improve the side protection; it is harder and typically has a smoother surface finish when compared to chromium coating.
2011-04-12
Technical Paper
2011-01-0471
Jiwoong Ha, Yujong Kim, Jiho Lim
This paper proposes an alternative methodology to construct a dynamic failure model of spot welds under combined axial and shear loading conditions for auto-body crash analyses performing cross-tension tests and lap-shear tests which are substitution of pure-shear tests. To construct a failure model of a spot weld proposed by Song and Huh, failure tests of spot welds with an imposed angle to the weldment have to be carried out at an interval of 15° from 0° to 90°. In the general case, it was suggested that the β value of 1.45 from the results of the failure load of cross-tension tests and pure-shear tests can be used for constructing their failure model. However, the scheme is not practical because of difficulties in making pure-shear specimens with the same welding conditions of two-sheet spot weld because the pure-shear specimen is generally prepared with three-sheet spot weld.
2011-04-12
Technical Paper
2011-01-0656
Jason A. Lustbader, John P. Rugh, Brianna R. Rister, Travis S. Venson
In the United States, intercity long-haul trucks idle approximately 1,800 hrs per year primarily for sleeper cab hotel loads, consuming 838 million gallons of diesel fuel [1]. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is working on solutions to this challenge through the CoolCab project. The objective of the CoolCab project is to work closely with industry to design efficient thermal management systems for long-haul trucks that keep the cab comfortable with minimized engine idling. Truck engine idling is primarily done to heat or cool the cab/sleeper, keep the fuel warm in cold weather, and keep the engine warm for cold temperature startup. Reducing the thermal load on the cab/sleeper will decrease air conditioning system requirements, improve efficiency, and help reduce fuel use. To help assess and improve idle reduction solutions, the CoolCalc software tool was developed.
2011-04-12
Technical Paper
2011-01-0240
Saurav Talukdar, Salil Kulkarni
The planar rigid bicycle model is one of the most popular models used in vehicle dynamics. It has widely been used in studying vehicle handling characteristics and designing steering control system for vehicles. This paper analyses a modified dynamic model called the "Elastic Bicycle Model." This model improves upon the classical bicycle model by taking into account the flexibility of the vehicle frame by using concepts from the Euler beam theory. Complete set of the resulting dynamic equations of this model are presented. Non-dimensional versions of the equations are used to investigate the steady state response of the model. Finally, the results of the response study obtained by modeling a small truck with an elastic model and the classical bicycle model are presented. These include the steady state solutions as function of different parameters as well as a transient solution in response to a saw-tooth steering input and a step input. Octave® has been used for simulation purpose.
2011-04-12
Journal Article
2011-01-0183
Brad Hopkins, Saied Taheri
Models for off-road vehicles, such as farm equipment and military vehicles, require an off-road tire model in order to properly understand their dynamic behavior on off-road driving surfaces. Extensive literature can be found for on-road tire modeling, but not much can be found for off-road tire modeling. This paper presents an off-road tire model that was developed for use in vehicle handling studies. An on-road, dry asphalt tire model was first developed by performing rolling road force and moment testing. Off-road testing was then performed on dirt and gravel driving surfaces to develop scaling factors that explain how the lateral force behavior of the tire will scale from an on-road to an off-road situation. The tire models were used in vehicle simulation software to simulate vehicle behavior on various driving surfaces. The simulated vehicle response was compared to actual maximum speed before sliding vs. turning radius data for the studied vehicle to assess the tire model.
2011-04-12
Journal Article
2011-01-0178
Jeff Howell
Vehicles on the road operate in the turbulent flow field resulting from the combined effects of the natural wind and the wakes of other vehicles. While substantial data exists on the properties of the natural wind, much less information is available for the wake properties of road vehicles. The wake information available for road vehicle shapes is mainly restricted to the near wake region, but to understand the vehicle operating environment it is the wake downstream of this region which is of interest. To determine the range of this area of interest requires some knowledge of the decay of the wake properties. From wind tunnel studies using small simple bluff bodies in free stream and in ground proximity the principle wake properties, velocity deficit and peak turbulence intensity have been measured. The maximum velocity deficit is shown to approximately decay with x-2/3, where x is the distance downstream, while turbulence intensity decays at a slightly slower rate.
2011-04-12
Technical Paper
2011-01-0174
Lisa Larsson, Torbjörn Wiklund, Lennart Löfdahl
The aim of the study was to investigate the cooling performance of two cooling package positions for distribution vehicles by using Computational Fluid Dynamics. The first cooling package was positioned in the front of the vehicle, behind the grill and the second position was at the rear of the vehicle. Each case was evaluated by its cooling performance for a critical driving situation and its aerodynamic drag at 90 km/h, where the largest challenge of an alternative position is the cooling air availability. The geometry used was a semi-generic commercial vehicle, based on a medium size distribution truck with a heat rejection value set to a fixed typical level at maximum power for a 13 litre Euro 6 diesel engine. The heat exchangers included in the study were the air conditioning condenser, the charge air cooler and the radiator. It was found that the main problem with the rear mounted cooling installation was the combination of the fan and the geometry after the fan.
2011-04-12
Technical Paper
2011-01-0191
Edoardo Sabbioni, Silvia Negrini, Francesco Braghin, Stefano Melzi lng
The paper investigates the interaction between soil and tractor tires through a 2D numerical model. The tire is schematized as a rigid ring presenting a series of rigid tread bars on the external circumference. The outer profile of the tire is divided into a series of elements, each one able to exchange a normal and a tangential contact force with the ground. A 2D soil model was developed to compute the forces at the ground-tire interface: the normal force is determined on the basis of the compression of the soil generated by the sinking of the tire. The soil is modeled through a layer of springs characterized by two different stiffness for the loading (lower stiffness) and unloading (higher stiffness) condition. This scheme allows to introduce a memory effect on the soil which results stiffer and keeps a residual sinking after the passage of the tire. The normal contact force determines the maximum value of tangential force provided before the soil fails.
2011-04-12
Journal Article
2011-01-0162
Ming Jiang, Huaizhu Wu, Kebing Tang, Minsuk Kim, Sivapalan Senthooran, Heinz Friz, Yingzhe Zhang
The engineering process in the development of commercial vehicles is facing more and more stringent emission regulations while at the same time the market demands for better performance but with lower fuel consumption. The optimization of aerodynamic performance for reduced drag is a key element for achieving related performance targets. Closely related to aerodynamics are wind noise and cabin soiling and both of them are becoming more and more important as a quality criterion in many markets. This paper describes the aerodynamic and aero-acoustic performance evaluation of a Dongfeng heavy truck using digital simulation based on a LBM approach. It includes a study for improving drag within the design of a facelift of the truck. A soiling analysis is performed for each aerodynamic result by calculating the accumulation of particles emitted form the wheels on the cabin. One of the challenges in the development process of trucks is that different cabin types have to be designed.
2011-04-12
Technical Paper
2011-01-0090
Wei Liu, Wenku Shi Sr
In this paper, a Magneto-Rheological (MR) fluid semi-active suspension system was tested on a commercial vehicle, a domestic light bus, to determine the performance improvements compared to passive suspensions. MR fluid is a material that responds to an applied magnetic field with a significant change in its rheological behavior. When the magnetic field is applied, the properties of such a fluid can change from a free-flowing, low viscosity fluid to a near solid, and this change in properties takes place in a few milliseconds and is fully reversible. A quarter suspension test rig was built out to test the nonlinear performance of MR damper. Based on a large number of experimental data, a phenomenological model of MR damper based on the Bouc-Wen hysteresis model was adopted to predict both the force-displacement behavior and the complex nonlinear force-velocity response.
2011-04-12
Technical Paper
2011-01-0108
Rainer Neumann, Thorsten Warwel
Due to the general requirements in the automotive industry to reduce the power consumption, fuel consumption rate and CO2 emission a new HID (High Intensity Discharge) bulb with only 25W is under development for front lighting systems. A first headlamp integrated in a hybrid vehicle is now launched as a first application in the market. The current regulation in ECE allows to get rid of the mandatory headlamp cleaning system and the automatic leveling requirement once the 25W HID bulb is applied. The reason for this is the objective luminous flux of the 25W HID bulb, which emits less than 2000 lm, a boundary defined in the regulation, where a headlamp cleaning and an automatic leveling is requested. That simplifies especially the integration in smaller vehicles and electric and hybrid vehicles. The paper describes the special design of the headlamp, the projector unit, the light performance, packaging advantages and future outlook of further applications in the near future.
2011-04-12
Technical Paper
2011-01-0109
Flavio Cimolin, Michele Rabito, Andrea Menotti
A complete methodology for the thermo-mechanical analysis of optical devices for the automotive industry is presented. The objective is to predict the thermal field all over the lamp, highlighting the zones with risk of melting, and the deformations and stresses associated with it. The proposed approach is based on a Computational Fluid-Dynamic (CFD) simulation capable of capturing all the heat transfer phenomena occurring inside and outside the lamp: conduction between different components of the device, natural convection associated with density changes in air (buoyancy effects), and radiation heat transfer. The latter requires a fairly complex modeling strategy in order to provide a satisfactory (and conservative) treatment for the source of power, i.e. the filament, which can be obtained by means of a proper inclusion of transparency.
2011-04-12
Technical Paper
2011-01-0116
Josef Schug
Today, LED automotive exterior lighting is already widely used on high end and upper middle class vehicles. We see already first examples of application as the standard lighting solution even in the mid class segment. A compact design and the feasibility of car life sealed solution is a strong argument to use LEDs for CHMSLs. Long lifetime and new styling opportunities speak for LEDS in front or rear position lights as well as in daytime running lamps;. Mainstream penetration of LED lighting solutions will first happen for functions where the benefits of LEDs have the highest positive impact and where this value can be realized in the most cost-effective way. During the different phases of the introduction of LEDs different requirements dominate the decision process. Providing unique styling opportunity and showing advanced technical functionality is leading for the early adopters.
Viewing 1 to 30 of 7617

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