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Journal Article

Virtual Motorsports as a Vehicle Dynamics Teaching Tool

2008-12-02
2008-01-2967
The paper describes a ‘virtual motorsports’ event developed by the University of Windsor Vehicle Dynamics and Control Research Group. The event was a competitive project-based component of a Vehicle Dynamics course offered by the University's Department of Mechanical, Automotive, & Materials Engineering. The simulated race was developed to provide fourth year automotive engineering students with design and race experience, similar to that found in Formula SAE®or SAE Baja®, but within the confines of a single academic semester. The project, named ‘Formula463’, was conducted entirely within a virtual environment, and encompassed design, testing, and racing of hi-fidelity virtual vehicle models. The efficacy of the Formula463 program to provide students with a design experience using model based simulation tools and methods has been shown over the past two years. All of the software has been released under a General Public License and is freely available on the authors website.
Technical Paper

Uses for Stabilized Aluminum Foam in Crashworthiness and Strengthening Applications

2003-03-03
2003-01-1295
Stabilized Aluminum Foam (SAF) is a material produced by introducing gas bubbles into molten aluminum. Two examples will be used to illustrate the potential use of SAF in energy absorption and structural reinforcement applications. The first is use of SAF in a crashbox to absorb energy in a 15km/hr collision and prevent damage to the rails as part of a front-end energy management system. The second is as a filler in a hollow structure subject to bending loads, which potentially could find application in rails and pillars. By filling a hollow structure with SAF, the bending strength is increased dramatically while the weight increases are not significant. Numerical modeling using LS DYNA gave very good agreement with experimental results.
Technical Paper

Transient Response of Minichannel Heat Exchanger Using Al2O3-EG/W Nanofluid

2016-04-05
2016-01-0229
A numerical study is performed to investigate the transient heat transfer and flow characteristics of aluminum oxide (Al2O3) nanoparticles dispersed in 50:50 ethylene glycol/water (EG/W) base fluid in a multipass crossflow minichannel heat exchanger. The time dependent thermal responses of the system in a laminar regime are predicted by solving the conservation equations using the finite volume method and SIMPLE algorithm. The transient regime is caused by a step change of nanofluid mass flow rate at the inlet of the minichannel heat exchanger. This step change can be analogous with a thermostat operation. In this study, three volume fractions up to 3 percent of Al2O3 nanoparticles dispersed to the base fluid EG/W are modeled and analyzed. In the numerical simulation, Al2O3-EG/W nanofluid is considered as a homogenous single-phase fluid. An analysis of the transient response for the variation of nanofluids volume concentrations is conducted.
Journal Article

Suitability Assessment of an Uncalibrated Body Force Based Fan Modeling Approach to Predict Automotive Underhood Airflows

2021-04-06
2021-01-0820
The automotive fan is a critical component of the cooling module, providing the majority of the cooling airflow over the heat exchangers and to underbody components at low speed, idle, and key-off conditions. Accurately predicting the performance of the automotive cooling fan is critical for sizing heat exchangers and ensuring that underhood and underbody components remain below target temperatures. This is normally done with computational fluid dynamics, but in a full-vehicle simulation it is impractical to model the rotation of the fan blades using a sliding mesh approach. Thus, simplified models which capture the fan behavior are employed. In this paper, a body force-type fan modeling approach is adopted and assessed. Many industrial fan models are calibrated based on experiments or higher-fidelity simulations. This can slow the design process. The approach employed eliminates this step, requiring only fan geometry information and no a-priori performance data.
Journal Article

Simulation of the Axial Cutting Deformation of AA6061-T6 Round Tubes Utilizing Eulerian and Mesh Free Finite Element Formulations

2008-04-14
2008-01-1117
Experimental and numerical studies have been completed on the deformation behaviour of round AA6061-T6 aluminum extrusions during an axial cutting deformation mode employing both curved and straight deflectors to control the bending deformation of petalled side walls. Round extrusions of length 200 mm with a nominal wall thickness of 3.175 mm and an external diameter of 50.8 mm were considered. A heat treated 4140 steel alloy cutter and deflectors, both straight and curved, were designed and manufactured for the testing considered. The four blades of the cutter had an approximate average thickness of 1.00 mm which were designed to penetrate through the round AA6061-T6 extrusions. Experimental observations illustrated high crush force efficiencies of 0.82 for the extrusions which experienced the cutting deformation mode with the deflectors. Total energy absorption during the cutting process was approximately 5.48 kJ.
Technical Paper

Separation and Liberation Factors in Designing for Automotive Materials Recovery

2004-03-08
2004-01-0471
One critical aspect of design-for-environment efforts is to increase the effectiveness of materials recovery from end-of-life vehicles. Recovery itself depends on both the amount of material recovered and the purity of the material stream. Shredding, and screening are often used to separate recyclable materials from wastes. However, with the increasing amount of composite components, particularly those made from plastics, separation processes may be inadequate. Instead, liberation processes, which reduce the physical joints between materials, are also important. In this research, samples of ABS and PVC plastics were assembled into various configurations, ground up, and then characterized by their size distributions and degrees of liberation. Two primary fastening methods - adhesive and riveting - were used to simulate how plastic components would be actually attached together.
Journal Article

Rotary Fatigue Analysis of Forged Magnesium Road Wheels

2008-04-14
2008-01-0211
Fatigue analysis incorporating explicit finite element simulation was conducted on a forged magnesium wheel model where a rotating bend moment was applied to the hub to simulate rotary fatigue testing. Based on wheel fatigue design criteria and a developed fatigue post-processor, the safety factor of fatigue failure was calculated for each finite element. Fatigue failure was verified through experimental testing. Design modifications were proposed by increasing the spoke thickness. Further numerical and experimental testing indicated that the modified design passed the rotary fatigue test.
Technical Paper

Roof Strength Requirement for Vehicles Involved in Rollover Crash

2008-04-14
2008-01-0510
Rollover crash is one of the most serious safety problems for light weight vehicles. In the USA, rollover crashes account for almost one-third of all occupant fatalities in light weight vehicles. Similar statistics are found for other countries. Thus, rollover crashes have received significant attention in recent years. In the USA and Canada, automotive manufacturers are required to comply with the roof strength requirement of “1.5 times the unloaded vehicle weight” to ensure safety in rollover. NHTSA is currently considering a set of countermeasures to improve the rollover safety, where one of the proposals is to increase the roof strength limit to “2.5 times the unloaded vehicle weight”. This increased roof strength limit seemingly has been motivated based on the benchmark study of current vehicle fleet.
Journal Article

Residual Stresses and Dimensional Changes in Ferritic Nitrocarburized Navy C-rings and Prototype Stamped Parts Made from SAE 1010 Steel

2009-04-20
2009-01-0425
Nitrocarburizing is an economical surface hardening process and is proposed as an alternative heat treatment method to carbonitriding. The focus of this study is to compare the size and shape distortion and residual stresses resulting from the ferritic nitrocarburizing and gas carbonitriding processes for SAE 1010 plain carbon steel. Gas, ion and vacuum nitrocarburizing processes utilizing different heat treatment temperatures and times were performed to compare the different ferritic nitrocarburizing processes. Navy C-Ring specimens and prototype stamped parts were used to evaluate size and shape distortion. X-ray diffraction techniques were used to determine the residual stresses in the specimens. Overall, the test results indicate that the nitrocarburizing process gives rise to smaller dimensional changes than carbonitriding, and that the size and shape distortion can be considerably reduced by applying appropriate ferritic nitrocarburizing procedures.
Technical Paper

Real-time Heat Release Analysis for Model-based Control of Diesel Combustion

2008-04-14
2008-01-1000
A number of cylinder-pressure derived parameters including the crank angles of maximum pressure, maximum rate of pressure rise, and 50% heat released are considered as among the desired feedback for cycle-by-cycle adaptive control of diesel combustion. For real-time computation of these parameters, the heat release analyses based on the first law of thermodynamics are used. This paper intends to identify the operating regions where the simplified heat release approach provides sufficient accuracy for control applications and also highlights those regions where its use can lead to significant errors in the calculated parameters. The effects of the cylinder charge-to-wall heat transfer and the temperature dependence of the specific heat ratio on the model performance are reported. A new computationally efficient algorithm for estimating the crank angle of 50% heat released with adequate accuracy is proposed for computation in real-time.
Journal Article

Preliminary Investigation of Exhaust Pressure Waves in a Single Cylinder Diesel Engine and the Impacts on Aftertreatment Sprays

2017-03-28
2017-01-0616
The pressure wave actions were investigated in the exhaust system of a single cylinder diesel engine through both experimental and simulation methods. The characteristics of the exhaust pressure waves under different engine operating conditions, such as engine load and exhaust backpressure, were examined. The results showed that the strength of the exhaust pressure wave was affected by both the in-cylinder pressure and the exhaust backpressure in the exhaust system during the period when the exhaust valves were open. The exhaust gas flow velocity was also estimated by the one dimensional simulation tool AVL BOOST™. The results suggested that the velocity of the exhaust gas fluctuated during the engine cycle, and followed trends similar to the exhaust pressure wave. The transient gas flow velocity was high when there was a strong compression wave, and it was reduced when the pressure fluctuations in the exhaust manifold were small.
Technical Paper

Power Management Methodologies for Fuel Cell-Battery Hybrid Vehicles

2010-04-12
2010-01-0849
The implementation of fuel cell-battery hybrid vehicles requires a supervisory control strategy that manages the power distribution between the fuel cell and the energy storage device (i.e., battery). Several advanced control methods have already been developed and published in literature. However, most control methods have been developed for different vehicle types and using different mathematical models. The performance of these power management methods have not been directly compared for the same application. This study aims at obtaining direct analytical comparisons, which will provide useful insight in selecting a power management method for fuel cell-battery hybrid vehicles.
Technical Paper

Oxygenated Fuels as Reductants for Lean NOx Trap Regeneration

2024-04-09
2024-01-2132
The push for environmental protection and sustainability has led to strict emission regulations for automotive manufacturers as evident in EURO VII and 2026 EPA requirements. The challenge lies in maintaining fuel efficiency and simultaneously reducing the carbon footprint while meeting future emission regulations. Alcohol (primarily methanol, ethanol, and butanol) and ether (dimethyl ether) fuels, owing to their comparable energy density to existing fuels, the comparative ease of handling, renewable production, and suitable emission characteristics may present an attractive drop-in replacement, fully or in part as an additive, to the gasoline/diesel fuels, without extensive modifications to the engine geometry. Additionally, lean and diluted combustion are well-researched pathways for efficiency improvement and reduction of engine-out emissions of modern engines.
Technical Paper

Numerical Investigation of Active and Passive Cooling Systems of a Lithium-Ion Battery Module for Electric Vehicles

2016-04-05
2016-01-0655
In this work, a pseudo three-dimensional coupled thermal-electrochemical model is established to estimate the heat generation and temperature profiles of a lithium ion battery as functions of the state of the discharge. Then, this model is used to investigate the effectiveness of active and passive thermal management systems. The active cooling system utilizes cooling plate and water as the working fluid while the passive cooling system incorporates a phase change material (PCM). The thermal effects of coolant flow rate examined using a computational fluid dynamics model. In the passive cooling system, Paraffin wax used as a heat dissipation source to control battery temperature rise. The effect of module size and battery spacing is studied to find the optimal weight of PCM required. The results show that although the active cooling system has the capability to reduce the peak temperatures, it leads to a large temperature difference over the battery module.
Technical Paper

Noise Cancellation Technique for Automotive Intake Noise Using A Manifold Bridging Technique

2005-05-16
2005-01-2368
Due to considerable efforts of automobile manufacturers to attenuate various noise sources within the passenger compartment, other sources, including induction noise have become more noticeable. The present study investigates the feasibility of using a non-conventional noise cancellation technique to improve the acoustic performance of an automotive induction system by using acoustic energy derived from the exhaust manifold as the dynamic noise source to cancel intake noise. The validity of this technique was first investigated analytically using a computational engine simulation software program. Using these results, a physical model of the bridge was installed and tested on a motored engine. The realized attenuation of the intake noise was evaluated using conventional FFT analysis techniques as well as psychoacoustic metrics including loudness, sharpness, roughness and fluctuation strength.
Technical Paper

Modular Design and Methods to Optimize Seat Complete Assemblies

2017-03-28
2017-01-1309
Modularity in product architecture and its significance in product development have become an important product design topics in the last few decades. Several Product Modularity definitions and methodologies were developed by many researchers; however, most of the definitions and concepts have proliferated to the extent that it is difficult to apply one universal definition for modular product architecture and in product development. Automotive seat modular strategy and key factors for consideration towards modular seat design and assemblies are the main focus of this work. The primary objectives are focused on the most “natural segmentation” of the seat elements (i.e., cushions, backs, trims, plastics, head restraints, etc.) to enable the greatest ease of final assembly and greatest flexibility for scalable feature offerings around common assembly “hard-points.”
Technical Paper

Metrics for Evaluating the Ride Handling Compromise

2010-04-12
2010-01-1139
Though the purpose of a vehicle's suspension is multi-faceted and complex, the fundamentals may be simply stated: the suspension exists to provide the occupants with a tolerable ride, while simultaneously ensuring that the tires maintain good contact with the ground. At the root of the familiar ride/handling compromise, is the problem that tuning efforts which improve either grip or handling are generally to the detriment of the other. This study seeks to set forth a clear means for examining the familiar ride/handing compromise, by first exploring the key ideas of these terms, and then by describing the development of content-rich metrics to permit a direct optimization strategy. For simplicity, the optimization problem was examined in a unilateral manner, where heave (vertical; z-axis) behaviour is examined in isolation, though the methods described herein may be extended to pitch and roll behaviour as well.
Technical Paper

Lumped Parameter Thermal Network Modeling for Online Temperature Prediction of Permanent Magnet Synchronous Motor for Different Drive Cycles in Electric Vehicle Applications

2020-04-14
2020-01-0455
Electric vehicle is increasingly becoming popular and an alternative choice for the consumers because of its environment-friendly operation. Permanent magnet synchronous machines are widely and commonly used as traction motors since they provide higher torque and power density. High torque and power density mean higher current which eventually causes higher temperature rise in the motor. Higher temperature rise directly affects the motor output. Standard tests for UDDS (Urban Dynamometer Driving Schedule) and HWFET (Highway Fuel Economy Driving Schedule) drive cycles are used to determine performance of traction motors in terms of torque, power, efficiency and thermal health. Traction motors require high torque at low speed for starting and climbing; high power at high speed for cruising; wide speed range; a fast torque response; high efficiency over wide torque and speed ranges and high reliability.
Technical Paper

Laser Welding of Elastomers to Polypropylene

2003-03-03
2003-01-1134
The effects of varying laser-welding parameters were studied for the welding of the thermoplastic elastomer EPDM to glass filled polypropylene. Through-thickness scanning transmission welding (contour welding) was carried out with a diode laser with a wavelength of 940 nm using various power levels up to 150W and line speeds up to 2500 mm/minute. The observable weld attributes: weld strengths, weld widths, and failure modes, have been tabulated and discussed.
Technical Paper

Kinematic Analysis of a 6DOF Gantry Machine

2015-04-14
2015-01-0497
Gantry robots are mainly employed for applications requiring large workspace, with limited higher manipulability in one direction than the others. The Gantries offer very good mechanical stiffness and constant positioning accuracy, but low dexterity. Common gantries are CNC machines with three translational joints XYZ (3DOF) and usually with an attached wrist (+3DOF). The translational joints are used to move the tool in any position in the 3D workspace. The wrist is used to orient the tool by rotation about X, Y and Z axis. This standard kinematic structure (3T3R) produces a rectangular workspace. In this paper a full kinematic model for a 6DOF general CNC (gantry) machine is presented, along with the Jacobian matrix and singularity analysis. Using Denavit-Hartenberg convention, firstly, the general kinematic structure is presented, in order to assign frames at each link. The forward kinematic problem is solved using Maple 17 software.
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