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An investigation was performed to study the effects of convection, diffusion and thermophoresis on diesel exhaust soot deposition inside a plate-type rectangular cooling section for recirculation (EGR) applications since deposited soot can be detrimental to the heat transfer efficiency of EGR cooling devices. A non-destructive neutron radiography technique was used to measure the soot deposition thickness distribution on the plate surface inside the cooling chamber. The chamber cooled with an inlet water coolant of 20 and 40°C, was installed in a modified exhaust system of a 2.4kW diesel engine and subjected to a mass flow rate of 20kg/hr of diesel exhaust ranging 0 to 3 hours with the exhaust gas temperature at 260°C upstream of the cooling chamber. In this work, the effect of cooling temperature and operation time on thermophoretic deposition was investigated.

An investigation was performed to study the soot deposition and its effect on heat transfer in a cooled cylindrical section. The soot layer thickness was measured using a non-destructive neutron radiography technique. Experiments were performed for a diesel exhaust mass flow rate of 20kg/hr or Reynolds number of approximately 9,000, initial inlet coolant temperatures of approximately 22 and 40°C, and exposure times from 1 to 3 hours. The results show that the nominal soot layer thickness was approximately uniform in the flow direction, hence, the thicker soot layer observed near the entrance by Ismail et al. [8] and de la Cruz et al. [9] was due to entrance effects. The deposited soot layer shows evidence of long wavy thickness variations that appears to be due to a soot re-entrainment and re-deposition moving bed type mechanism. The soot thickness increased and the long wavy variations persisted for larger soot thicknesses when the coolant temperature or wall temperature was lower.

Magnesium AZ80 is a medium strength alloy with good corrosion resistance and very good forging capability which offers an affordable commercial alternative to the Mg ZK60 alloy used for wheels in racing cars. Extending the market of Mg AZ80 alloy to automotive wheels requires a better understanding of macro- and micro-properties of this structural material, especially its forging behaviour. In this study the deformation behaviour of Mg AZ80 alloy is characterized by uniaxial compression tests from ambient to 420°C at a variety of strain rates using a Gleeble 1500 simulator. A constitutive relationship coupling materials work hardening and strain rate and temperature dependences is calibrated based on test results. This flow behaviour is input into a finite element model to simulate the forging operation of an automotive wheel with ABAQUS codes.

The constitutive behavior of aluminum alloy sheet and their resistance spot welds at large strains is critical for light weight vehicle design analysis and life prediction. However, data from uniaxial tensile tests are usually limited to small strains or by material instability. A novel technique was developed using digital image correlation coupled with a modified shear test to directly measure the stress - strain curves of aluminum alloy sheet at large strains. The modified shear sample prevents end rotation of the shear zone as compared to the ASTM B831 test. The results show that the effective stress - effective strain curves from shear tests match those obtained by uniaxial tension, but only by incorporating material anisotropy using the Barlat-Lian yield function. For the first time, the technique was applied to aluminum resistance spot welds to determine both the shear strength and stress-strain curves of spot welds at large strains.

In recent years, environmental regulations in the automotive industry have become increasingly strict, particularly with respect to emissions from diesel engines. Large amounts of these harmful emissions are released during the cfold start of a vehicle, due to the catalytic converter system not yet reaching its light-off temperature. This paper presents an induction heating system which heats the catalytic converter during a cold start, reducing the time for it to reach light-off temperature, and thus reducing cold-start emissions. Detailed dynamometer testing results are used to develop vehicle models of the induction heating system for a diesel Peugeot 308 light duty vehicle. The model is used to quantify the changes in hydrocarbons (HC), carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), nitrogen oxide (NOx), and fuel consumption on a variety of standard drive cycles.

We have studied the formability of continuous strip cast (CC) AA5754 aluminum alloy for automotive applications. Strip casting technology can considerably reduce material cost compared with conventional direct chill (DC) cast aluminum sheets. However, the CC material tends to exhibit much less post-localization deformation and lower fracture strains compared with DC sheets with similar Fe content, although both alloys show similar strains for the onset of localization. Bendability of the CC alloy is also found to be inferior. The inferior behavior (post-necking and bendability) of the CC alloy can be attributed to the higher incidence of stringer-type particle distributions in the alloy. The formability of the AA5754 alloy has also been studied using two dimensional microstructure-based finite element modeling. The microstructures are represented by grains and experimentally measured particle distributions.

Using urea-based Selected Catalytic Reduction (SCR) systems is an effective way in diesel engine after-treatment systems to meet increasingly stringent emission regulations. The amount of urea injection is critical to achieve high NOx reduction efficiency and low ammonia slip and overdosing or under-dosing of urea injection need to be avoided. One of the difficulties in urea injection amount control lies in the accurate measurement/estimation of the urea injection mass. To effectively address this issue, this paper defined a correction factor for under-dosing or overdosing detection and correction and proposed two methods to identify the correction factor. The first method is based on urea pump model and line pressure. Through frequency analysis, the relation between the urea pump speed and power spectrum characteristics of the line pressure by using FFT method was revealed.

The purpose of this work was to initiate a comparative evaluation of the aqueous corrosion resistance of ferritic stainless steels currently used to fabricate automotive exhaust systems. Both acid condensate and double loop electrochemical potentiokinetic reactivation (DL-EPR) testing using both as-received and heat treated test coupons prepared from Types 409, 409Al, 436 and 439 stainless steel was conducted for this purpose. A truncated version of an in-house acid condensate testing protocol revealed that Type 409Al stainless steel was the most resistant to corrosion of the four ferritic stainless steels examined, whereas Type 409 stainless steel was the least resistance to corrosion.

The purpose of this study was to conduct a comparative corrosion assessment of alloys and coating schemes of interest for the fabrication of multi-material lightweight vehicle architectures. Alloys considered for this application included galvanized high strength low alloy steel, aluminum alloy AA6111 and magnesium alloy ZEK100. The coating scheme considered for corrosion protection included a layered paint top-coat scheme that was applied to a pre-treated surface. The pre-treatments included an alloy-specific commercial conversion coating (CC) and a plasma electrolytic deposition (PED) process that was applied only to the ZEK100 material. The corrosion assessment of the scribed coated alloy panels was conducted after 1000 h exposure in the ASTM B117 salt fog environment. Characterization of the mode and extent of corrosion damage observed and the role played by the exposed alloy microstructure utilized both light optical microscopy and electron microscopy.

This paper presents a model for predicting the energy consumption of a 2017 Chevrolet Bolt electric vehicle. The model is validated using 93 measured drive cycles covering in excess of 10,600 kilometres of driving and temperatures from −8 to 32 °C. The mechanical road load acting on the vehicle is calculated via ABC parameters from the publicly available US Environmental Protection Agency (EPA) Annual Certification Data database. The vehicle model includes wheel diameter, gear ratio, rated electric machine torque and power, 12V accessory load based off measurements, measured electric machine efficiency obtained from a publication from General Motors, and modelled inverter efficiency. Assumptions are made regarding gearbox losses as well. To ensure accuracy under real-world conditions, road grade, temperature effects, and heating and cooling energy are included as well. The model predicts an EPA range of 380 km, which is very close to the 383 km rating.

As centralization of automotive E/E (Electrical and/or Electronic) architectures becomes reality for future vehicles, it is crucial that existing assets be reused in the most efficient and effective manner. We report on our experience developing a new centralized E/E architecture for a propulsion domain, and migrating the corresponding propulsion elements of an existing decentralized, CAN-based architecture to a prototype of the centralized propulsion domain. Our migration adopts automotive Ethernet and supporting standards as a next-generation communications backbone technology; a next-generation computation platform from automotive supplier NXP; and a new automotive virtualization solution from OpenSynergy. We discuss aspects of legacy software reuse and adaptation; modification of vehicle HiL simulation models used in testing; existing vendor tool support; and implications arising from functional safety and the ISO 26262 standard.

This paper presents the characteristics of more than 260 trim levels for over 50 production electric vehicle (EV) models on the market since 2014. Data analysis shows a clear trend of all-wheel-drive (AWD) powertrains being increasingly offered on the market from original equipment manufacturers (OEMs). The latest data from the U.S. Environmental Protection Agency (EPA) shows that AWD EVs have seen a nearly 4 times increase in production from 21 models in 2020 to 79 models in 2023. Meanwhile single axle front-wheel-drive (FWD) and rear-wheel-drive (RWD) drivetrains have seen small to moderate increases over the same period, going from 9 to 11 models and from 5 to 12 models, respectively. Further looking into AWD architectures demonstrates dual electric machine (EM) powertrains using different EM types on each axle remain a small portion of the dual-motor AWD category.