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Dramatic changes in transportation are coming. Cities and states looking to be at the forefront and reap the benefits, need an engaged and informed citizenry. Hear how the SAE Demo Day in Tampa supported Florida's AV initiatives and can benefit states nationwide.

In May 2018, SAE International in partnership with THEA and leading AV technology companies gave citizens in Tampa a chance to test ride the future. The event included a pre- and post-ride survey, a ride in an automated vehicle, interactive displays and engagement with industry experts. See highlights of the event and feedback from participants.

In “Simulation Tools for Engine Design” engineers from Ricardo Software discuss the use of simulation software in new powertrain development. Another engineer, this time from General Motors, talks about how simulation tools helped them solve the challenge of fuel flow reversion while designing the new turbocharged Cadillac V6 engine. This episode highlights: The challenge of simulating complex and combined systems in one vehicle An example of how a library of components in a software package can be chosen to form a specific system and analyzed How computational fluid dynamics simulation tools were used to help redesign a new planum Also Available in DVD Format To subscribe to a full-season of Spotlight on Design, please contact SAE Corporate Sales: CustomerSales@sae.org or 1-888-875-3976.

“Spotlight on Design” features video interviews and case studies, focusing on technology breakthroughs, hands-on testimonials, and the importance of fundamentals. Viewers are virtually taken to industry labs and research centers to learn how design engineers solve real-life problems. These challenges include enhancing product performance, reducing costs, improving quality and safety, while decreasing environmental impact, and achieving regulatory compliance. In the episode “Additive Manufacturing: 3D Printing in the Automotive Industry” (20:00), engineers from Fiat Chrysler Corporation (FCA) explain the importance of using 3D printing to test multiple design scenarios and develop solutions that can be quickly evaluated on test tracks. And Local Motors shows how it builds a vehicle from the ground up with a 3D printer, and without a traditional assembly line.

“Spotlight on Design” features video interviews and case studies, focusing on technology breakthroughs, hands-on testimonials, and the importance of fundamentals. Viewers are virtually taken to industry labs and research centers to learn how design engineers solve real-life problems. These challenges include enhancing product performance, reducing cost, improving quality and safety, while decreasing environmental impact, and achieving regulatory compliance. In the episode “Engine Development for Performance and Efficiency” (22:00), engineers from Ricardo and General Motors explain the importance of lessons learned on the race tracks, how using the appropriate design and simulation tools expedite development, and present the new testing frontiers now available with 3D printing.

In “Using Turbocharging in New Engine Design” (9:23), engineers from Schaeffler Group USA and McLaren Performance Tech explain what turbocharging is, and what it can do to improve both the power output of an engine and its fuel efficiency. Another engineer from the General Motors Powertrain group talks about how turbocharging was used in the new engine design for the Cadillac CT6. This episode highlights: The lessons learned from when turbocharging was first used to help heavy-duty trucks go uphill The experience acquired from car racing using turbo-charged engines The advantages of using turbo charging to decrease the size of engines without losing power output Also Available in DVD Format To subscribe to a full-season of Spotlight on Design, please contact SAE Corporate Sales: CustomerSales@sae.org or 1-888-875-3976.

“Spotlight on Design” features video interviews and case study segments, focusing on the latest technology breakthroughs. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. Fuel efficiency, or simply put, how to get more mileage out of the same amount of fuel has become one of the main goals to be achieved by new automotive technologies in the future, thanks in part to new government regulations. In the episode “Fuel Efficiency: Racing toward CAFE 2025” (21:24) AVL engineers show simulation and testing being used to design more fuel efficient vehicles, including the equipment that actually analyzes fuel economy.

“Spotlight on Design: Insight” features an in-depth look at the latest technology breakthroughs impacting mobility. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. Telematics, the convergence of telecommunications and informatics, uses electronic and computer technology built in to the vehicle to provide vehicle tracking, satellite navigation, wireless technology, and diagnostic information. In the episode “Diagnostics and Prognostics: Telematics Deep Dive” (8:09), an engineer from Delphi’s Telematics program discusses the advantages and challenges of telematics devices for the automotive industry, demonstrates the installation of an aftermarket telematics device, and shows how telematics can enhance diagnostics and preventative maintenance.

Formula SAE challenges students to conceive, design, fabricate, and compete with small formula-style racing car. 120 university teams from around the globe spend 8-12 months designing, building and preparing their vehicles for the competition. Learn why sponsors support Formula SAE and become a sponsor today!

The conference of choice for the sharing of technical knowledge and networking for the global on-road and off-road commercial vehicle industry. To learn more about this industry driven and industry relevant event, visit www.sae.org/events/comvec

The local equivalence ratio, Φ, was measured in fuel jets using laser-induced spontaneous Raman scattering in an optical heavy duty diesel engine. The measurements were performed at 1200 rpm and quarter load (6 bar IMEP). The objective was to study factors influencing soot formation, such as gas entrainment and lift-off position, and to find correlations with engine-out particulate matter (PM) levels. The effects of nozzle hole size, injection pressure, inlet oxygen concentration, and ambient density at TDC were studied. The position of the lift–off region was determined from OH chemiluminescence images of the flame. The liquid penetration length was measured with Mie scattering to ensure that the Raman measurement was performed in the gaseous part of the spray. The local Φ value was successfully measured inside a fuel jet. A surprisingly low correlation coefficient between engine-out PM and the local Φ in the reaction zone were observed.

The combustion timing in internal combustion engines affects the fuel consumption, in-cylinder peak pressure, engine noise and emission levels. The combination of an in-cylinder pressure sensor together with a direct injection fuel system lends itself well for cycle-to-cycle control of the combustion timing. This paper presents a method of controlling the combustion timing by the use of a cycle-to-cycle injection-timing algorithm. At each cycle the currently estimated heat-release rate is used to predict the in-cylinder pressure change due to a combustion-timing shift. The prediction is then used to obtain a cycle-to-cycle model that relates combustion timing to gross indicated mean effective pressure, max pressure and max pressure derivative. Then the injection timing that controls the combustion timing is decided by solving an optimization problem involving the model obtained.

Partially premixed combustion (PPC) is a promising way to achieve high thermal efficiency and low emissions, especially by using multiple injection strategies. The mechanisms behind PPC efficiency are still to be explained and explored. In this paper, multiple injections have been used to affect the gross indicated efficiency in an optical PPC engine modified from a Volvo MD13 heavy-duty diesel engine. The aim is both to improve and impair the gross indicated efficiency to understand the differences. The combustion natural luminosity is captured by a high-speed camera, and the distribution of fuel, oxygen, and temperature during the combustion process has been further explored by CFD simulation. The results show that with the right combination of the pilot, main, and post injection the gross indicated efficiency can be improved.

The effects of injection pressure and swirl ratio on the in-cylinder soot oxidation are studied using simultaneous PLIF imaging of OH and LII imaging of soot in an optical diesel engine. Images are acquired after the end of injection in the recirculation zone between two adjacent diesel jets. Scalars are extracted from the images and compared with trends in engine-out soot emissions. The soot emissions decrease monotonically with increasing injection pressure but show a non-linear dependence on swirl ratio. The total amount of OH in the images is negatively correlated with the soot emissions, as is the spatial proximity between the OH and soot regions. This indicates that OH is an important soot oxidizer and that it needs to be located close to the soot to perform this function. The total amount of soot in the images shows no apparent correlation with the soot emissions, indicating that the amount of soot formed is a poor predictor of the emission trends.

In a previous study, in order to investigate the effect of charge stratification on combustion behavior such as combustion efficiency and combustion phasing which also largely affects the emissions, an experiment was conducted in a heavy-duty compression ignition (CI) metal engine. The engine behavior and emission characteristics were studied in the transition from HCCI mode to PPC mode by varying the start of injection (SOI) timing. To gain more detailed information of the mixing process, in-cylinder laser diagnostic measurements, namely fuel-tracer planar laser induced fluorescence (PLIF) imaging, were conducted in an optical version of the heavy-duty CI engine mentioned above. To the authors’ best knowledge, this is the first time to perform fuel-tracer PLIF measurements in an optical engine with a close to production bowl in piston combustion chamber, under transition conditions from HCCI to PPC mode.

The partially premixed combustion (PPC) concept is regarded as an intermediate process between the thoroughly mixed Homogeneous charge compression ignition (HCCI) combustion and compression ignition (CI) combustion. It’s a combination of auto-ignition mode, a fuel-rich premixed combustion mode, and a diffusion combustion mode. The concept has both high efficiency and low soot emission due to low heat losses and less stratified fuel and air mixtures compared to conventional diesel CI. The mechanisms behind the combustion process are not yet very well known. This work focuses on the efficiency and the in-cylinder process in terms of fuel distribution and the initial phase of the combustion. More specifically, double injection strategies are compared with single injection strategies to achieve different levels of stratification, ranging from HCCI to PPC like combustion as well as poor (43%) to good (49%) of gross indicated efficiency.

Post-injection strategies aimed at reducing engine-out emissions of unburned hydrocarbons (UHC) were investigated in an optical heavy-duty diesel engine operating at a low-load, low-temperature combustion (LTC) condition with high dilution (12.7% intake oxygen) where UHC emissions are problematic. Exhaust gas measurements showed that a carefully selected post injection reduced engine-out load-specific UHC emissions by 20% compared to operation with a single injection in the same load range. High-speed in-cylinder chemiluminescence imaging revealed that without a post injection, most of the chemiluminescence emission occurs close to the bowl wall, with no significant chemiluminescence signal within 27 mm of the injector. Previous studies have shown that over-leaning in this near-injector region after the end of injection causes the local equivalence ratio to fall below the ignitability limit.

Methods for detection of the spatial position and timing of diesel ignition with improved accuracy are demonstrated in an optically accessible constant-volume chamber at engine-like pressure and temperature conditions. High-speed pressure measurement using multiple transducers, followed by triangulation correction for the speed of the pressure wave, permits identification of the autoignition spatial location and timing. Simultaneously, high-speed Schlieren and broadband chemiluminescence imaging provides validation of the pressure-based triangulation technique. The combined optical imaging and corrected pressure measurement techniques offer improved understanding of diesel ignition phenomenon. Schlieren imaging shows the onset of low-temperature (first-stage) heat release prior to high-temperature (second-stage) ignition. High-temperature ignition is marked by more rapid pressure rise and broadband chemiluminescence.

Mixing in wall-jets was investigated in an optical heavy-duty diesel engine with several injector configurations and injection pressures. Laser-induced fluorescence (LIF) was employed in non-reacting conditions in order to quantitatively measure local equivalence ratios in colliding wall-jets. A novel laser diagnostic technique, Structured Laser Illumination Planar Imaging (SLIPI), was successfully implemented in an optical engine and permits to differentiate LIF signal from multiply scattered light. It was used to quantitatively measure local equivalence ratio in colliding wall-jets under non-reacting conditions. Mixing phenomena in wall-jets were analyzed by comparing the equivalence ratio in the free part of the jet with that in the recirculation zone where two wall-jets collide. These results were then compared to φ predictions for free-jets. It was found that under the conditions tested, increased injection pressure did not increase mixing in the wall-jets.

In the automotive industry, the piezo-based in-cylinder pressure sensor is getting commercialized and used in production vehicles. For example, the pressure sensor offers the opportunity to design algorithms for estimation of engine emissions, such as soot and NO , during a combustion cycle. In this paper a zero-dimensional NO model for a diesel engine is implemented that will be used in real time. The model is based on the thermal NO formation and the Zeldovich mechanism using two non-geometrical zones: burned and unburned zone. The influence of EGR on combustion temperature was modeled using a well-known thermodynamic identity where specific heat at constant pressure is included. Specific heat will vary with temperature and the gas composition. The model was implemented in LabVIEW using tools specific for an FPGA (Field-Programmable Gate Array).