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Sliding wear of magnesium (Mg) engine cylinder bore surfaces and corrosion of Mg engine coolant channels are the two unsolved critical issues that automakers have to deal with in development of magnesium-intensive engines. In this paper, Plasma Electrolytic Oxidation (PEO) process was used to produce oxide coatings on AJ62 Mg alloy to provide wear and corrosion protection. In order to optimize the PEO process, orthogonal experiments were conducted to investigate the effect of PEO process parameters on the wear properties of PEO coatings. The PEO coatings showed a much better wear resistance, as well as a smaller friction coefficient, than the AJ62 substrate. The galvanic corrosion property of AJ62 Mg coupled with stainless steel and aluminum (Al) was investigated via immersion corrosion test in an engine coolant. Applying PEO coating on Mg can effectively prevent the galvanic corrosion attack to Mg.

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.

This research focuses on the injury potential of children seated in forward facing child restraint seats during frontal vehicle crashes. Experimental sled tests were completed in accordance to the Federal Motor Vehicle Safety Standard 213 using a Hybrid III three-year-old dummy in a five point child restraint system. A full vehicle crash test was completed in accordance to the Canadian Motor Vehicle Safety Standard 208 with the addition of a three-year-old Hybrid III crash test dummy, seated behind the passenger seat, restrained in the identical five-point child safety seat. Different child restraint finite element models were developed incorporating a subset of the apparatus used in the two experimental tests and simulated using LS-DYNA.

This study provides an overview of a novel method for evaluating in-vehicle speech intelligibility using the Speech Intelligibility Index (SII). The approach presented is based on a measured speech signal evaluated at the sentence Speech Reception Threshold (sSRT) in a simulated driving environment. In this context, the impact of different band importance functions in the evaluation of the SII using the Hearing in Noise Test (HINT) in a driving simulator is investigated.

In order to reduce the weight of an automotive engine, an aluminum (Al) alloy engine block with cast iron liner has been successfully used to replace the gray cast iron engine. For newly emerging Al linerless engine in which the low surface hardness of the aluminum alloy has to be overcome, a few surface processing technologies are used to protect the surface of cylinders. Among them, plasma transferred wire arc (PTWA) thermal spraying coating is becoming popular. Plasma electrolytic oxidation (PEO) coating is also proposed for increasing the wear resistance of aluminum alloy and reducing the friction between the cylinder and piston. In this work, a PEO coating with a thickness of ∼20 μm was prepared, and a high speed pin-on-disc tribometer was used to study the tribological behavior of the coating at oil lubricant conditions. Different surface roughness of the coating and a large range of the sliding speeds were employed for the tests.

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.

This research focuses on the response of the Q3, Hybrid III 3-year-old dummy and a child finite element model in a simulated 213 sled test. The Q3 and Hybrid III 3-year old child finite element models were developed by First Technology Safety Systems. The 3-year-old child finite element model was developed by Nagoya University by model-based scaling from the AM50 (50 percentile male) total human model for safety. The child models were positioned in a forward facing, five-point child restraint system using Finite Element Model Builder. An acceleration pulse acquired from an experimental 213 sled test, which was completed following the guidelines outlined in the Federal Motor Vehicle Safety Standard 213 using a Hybrid III 3-year-old dummy, was applied to the seat buck supporting the child restraint seat. The numerical simulations utilizing the Q3, Hybrid III 3-year-old and the child finite element model were conducted using the explicit non-linear finite element code LS-DYNA.

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.

Diesel engines operating in the low-temperature combustion (LTC) mode generally tend to produce very low levels of NOx and soot. However, the implementation of LTC is challenged by the higher cycle-to-cycle variation with heavy EGR operation and the narrower operating corridors. The robustness and efficiency of LTC operation in diesel engines can be enhanced with improvements in the promptness and accuracy of combustion control. A set of field programmable gate array (FPGA) modules were coded and interlaced to suffice on-the-fly combustion event modulations. The cylinder pressure traces were analyzed to update the heat release rate concurrently as the combustion process proceeds prior to completing an engine cycle. Engine dynamometer tests demonstrated that such prompt heat release analysis was effective to optimize the LTC and the split combustion events for better fuel efficiency and exhaust emissions.

Automotive steering wheels depend on a structural skeleton made of steel, aluminum, or magnesium to be the basis for the mechanical properties of the finished part. The mechanical properties of concern are the fatigue properties and the crash performance. The purpose of this study was to evaluate the crash and the fatigue performance of a steering wheel skeleton fabricated by high pressure die casting. Two materials were used to produce two groups of wheels with identical geometry. The production part was designed, optimized and fabricated with AM50A magnesium. The production magnesium component met all of the regulatory design and performance requirements. A small sample run was made in a proprietary aluminum - magnesium alloy. The fatigue and crash properties were evaluated empirically. In fatigue testing, the aluminum skeletons displayed a significant improvement, with respect to the magnesium skeletons, in the number of cycles to failure at the loads tested.

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.

Friction between the piston and cylinder accounts for large amount of the friction losses in an internal combustion (IC) engine. Therefore, any effort to minimize such a friction will also result in higher efficiency, lower fuel consumption and reduced emissions. Plasma electrolytic oxidation (PEO) coating is considered as a hard ceramic coating which can provide a dimpled surface for oil retention to bear the wear and reduce the friction from sliding piston rings. In this work, a high speed pin-on-disc tribometer was used to generate the boundary, mixed and hydrodynamic lubrication regimes. Five different lubricating oils and two different loads were applied to do the tribotests and the COFs of a PEO coating were studied. The results show that the PEO coating indeed had a lower COF in a lower viscosity lubricating oil, and a smaller load was beneficial to form the mixed and hydrodynamic lubricating regimes earlier.

Rally cars are among the most technologically advanced and complex race cars, with intercooled forced induction, adaptive all wheel drive and high-feature engine management being standard features for open class racers in all major North American Rally series. This high level of technology and complexity places additional burden on the service crews and mechanics charged with the task of preparing and repairing the vehicles during the competition. As such, it is of great importance that the brief service stops (thirty minutes per FIA regulation 17.2.2 [2008]) be executed as efficiently as possible. In the pursuit of valuable seconds, rally mechanics have shown a great deal of ingenuity, creating tools and procedures which are unique to the sport. One such innovation is the peg-style jack stand.

Individuals with hearing impairments often report hearing difficulties within the driving environment. This is an ever growing issue given the increasing population of senior aged drivers. In this study, Speech Intelligibility Index (SII) is used to predict in-vehicle speech intelligibility of individuals having common hearing impairments. The effect of hearing threshold levels obtained from audiograms and the impact of vehicle background noise measured for various vehicle operating conditions, road surface types and talker and listener configurations are investigated. This is done by using measured and user-defined speech spectra as described by ANSI S3.5-1997 (Methods for Calculation of the Speech Intelligibility Index). The results demonstrate poor speech intelligibility for most situations considered and provide evidence for the need to improve automotive interior sound quality in terms of speech intelligibility for hearing impaired drivers including aged drivers.

Highly accurate cylinder pressure data can be acquired using a wall-mounted and water-cooled quartz piezoelectric transducer. However, this type of transducer does not satisfy the cost and packaging constraints when used in a production engine application. A potential solution to these issues that has been the interest of many is the much smaller and less expensive optical fiber based pressure transducer. This research compares Kistler piezoelectric transducers to Optrand optical fiber transducers. The influence of the transducer type and mounting arrangement on the quality of cylinder pressure data was examined. The transducers were evaluated on a DaimlerChrysler 4.7L V-8 Compressed Natural Gas fuelled test engine. The analysis method is comprised of examining measured individual cycle and ensemble-averaged cylinder pressure records to assess the quality of the data and its usefulness for engine management.

A Split-Cycle engine fueled with methane has been constructed and operated at the University of Windsor. A split-cycle engine consists of two interconnected cylinders working together to preform the four engine strokes. Cylinder 1 preforms intake and compression strokes while cylinder 2 is where combustion, expansion and exhaust occur. The connecting high pressure crossover passage is where methane is injected, resulting in a well pre-mixed air-fuel mixture. Transfer occurs to the combustion cylinder near TDC, resulting in intense small scale turbulence that leads to short combustion durations under 30° CA. Short durations are achieved despite low engine speeds of 850-1200 rpm, late combustion phasing and part loads. Of note is the lean limit of operation of the engine at the equivalence ratio Φ = 0.85, which is high compared to other natural gas engines which have limits around Φ = 0.6.

This research focuses on comparing the biomechanical response of the head and neck of the Hybrid III 3-year-old anthropometric test device finite element model and pediatric cadaver data, under flexion-extension bending and axial tensile loading conditions. Previous experimental research characterized the quasi-static biomechanical response of the pediatric cervical spine under flexion-extension bending and tolerance in tensile distraction loading conditions. Significant differences in rotational and linear stiffness were found between the Hybrid III model and the pediatric cadaver data. In this research the biomechanical child cadaver neck response has been implemented into the 3-year-old Hybrid III child dummy FE model. An explicit finite element code (LS-DYNA) and the modified Hybrid III model were used to numerically simulate the previous cadaver tests and validate the altered Hybrid III neck.

This research focuses on the further development of a child finite element model whereby implementation of pediatric cadaver testing observations considering the biomechanical response of the neck of children under tensile and bending loading has occurred. Prior to this investigation, the biomechanical neck response was based upon scaled adult cadaver behaviour. Alterations to the material properties associated with ligaments, intervertebral discs and facet joints of the pediatric cervical spine were considered. No alteration to the geometry of the child neck finite element model was considered. An energy based approach was utilized to provide indication on the appropriate changes to local neck biomechanical characteristics. Prior to this study, the biomechanical response of the neck of the child finite element model deviated significantly from the tensile and bending cadaver tests completed by Ouyang et al.

In order to improve the fuel economy for future high-efficiency spark ignition engines, the use of advanced combustion strategies with an overall lean and/or exhaust gas recirculation diluted cylinder charge is deemed to be beneficial, provided a reliable ignition process available. In this paper, experimental results of igniting methane-air mixture by means of capacitive coupled ignition and multi-coil distributed spark ignition are presented. It is found that with a conventional spark plug electrode configuration, increase of spark energy does not proportionally enhance the ignition flame kernel development. The use of capacitive coupled ignition to enhance the initial transient power resulted in faster kernel growth compared to the conventional system. The distribution of the spark energy across a number of spark gaps shows considerable benefit.

Heat-release and cylinder pressure based adaptive fuel-injection control tests were performed on a modern common-rail diesel engine to improve the engine operation in the low-temperature combustion (LTC) region. A single shot injection strategy with heavy amount of exhaust gas recirculation (EGR) was used to modulate the in-cylinder charge conditions to achieve the low-temperature combustion. Adaptive fuel-injection techniques were used to anchor the cylinder pressure characteristics in the desired crank angle window and thereby stabilize the engine operation. The response of the adaptive control to boost, fueling, and engine speed variations was also tested. A combination of adaptive fuel-injection and automatic boost/back-pressure controls had helped to make the transient emissions comparable to the steady-state LTC emissions.