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An over-expanded spark ignited engine was investigated in this work via engine simulation with a design constrained, mechanically actuated Atkinson cycle mechanism. A conventional 4-stroke spark-ignited turbo-charged engine with a compression ratio of 9.2 and peak brake mean effective pressure of 22 bar was selected for the baseline engine. With geometry and design constraints including bore, stroke, compression ratio, clearance volume at top dead center (TDC) firing, and packaging, one over-expanded engine mechanism with over expansion ratio (OER) of 1.5 was designed. Starting with a validated 1D engine simulation model which included calibration of the in-cylinder heat transfer model and SI turbulent combustion model, investigations of the Atkinson engine including cam optimization was studied. The engine simulation study included the effects of offset of piston TDC locations as well as different durations of the 4-strokes due to the mechanism design.

Automotive exhaust noise is one of the major sources of noise pollution and it is controlled by passive control system (mufflers) and active control system (loudspeakers and active control algorithm). Mufflers are heavy, bulky and large in size while loudspeakers have a working temperature limitation. Carbon nanotube (CNT) speakers generate sound due to the thermoacoustic effect. CNT speakers are also lightweight, flexible, have acoustic and light transparency as well as high operating temperature. These properties make them ideal to overcome the limitations of the current exhaust noise control systems. An enclosed, coaxial CNT speaker is designed for exhaust noise cancellation application. The development of a 3D multi-physics (coupling of electrical, thermal and acoustical domains) model, for the coaxial speaker is discussed in this paper. The model is used to simulate the sound pressure level, input power versus ambient temperature and efficiency.

A three phase catalytic mathematical model was developed for analysis and optimization of the volatile reactor assembly (VRA) used on International Space Station (ISS) Water Processor. The Langmuir-Hinshelwood Hougen-Watson (L-H) expression was used to describe the surface reaction rate. Small column experiments were used to determine the L-H rate parameters. The test components used in the experiments were acetic acid, acetone, ethanol, 1-propanol, 2-propanol and propionic acid. These compounds are the most prevalent ones found in the influent to the VRA reactor. The VRA model was able to predict performance of small column data and experimental data from the VRA flight experiment.

The FlexRay serial data protocol is being considered in automotive vehicle architectures as an enabler for active safety, time critical systems due to the advantages it provides for time-determinism, increased data bandwidth, and multiple data channels to support fault tolerance strategies. To improve the robustness/availability of the electrical/physical layer when used for these critical applications, a FlexRay Active Star device is available. The Active Star is part of the physical layer and facilitates the creation of robust, fault tolerant network systems by partitioning the network into individual branches connected to one or more ECUs. This partitioning allows fault confinements and isolation activities to be performed at individual branches with minimal disruption to network communication. This paper describes the investigation of Active Star capabilities and some complexities related to their network integration.

The emerging need of building an efficient Electric Vehicle (EV) charging infrastructure requires the investigation of all aspects of Vehicle-Grid Integration (VGI), including the impact of EV charging on the grid, optimal EV charging control at scale, and communication interoperability. This paper presents a cloud-based simulation and testing platform for the development and Hardware-in-the-Loop (HIL) testing of VGI technologies. Although the HIL testing of a single charging station has been widely performed, the HIL testing of spatially distributed EV charging stations and communication interoperability is limited. To fill this gap, the presented platform is developed that consists of multiple subsystems: a real-time power system simulator (OPAL-RT), ISO 15118 EV Charge Scheduler System (EVCSS), and a Smart Energy Plaza (SEP) with various types of charging stations, solar panels, and energy storage systems.

One of the keys to a good reliable design is evaluating potential and past issues, ascertaining and then mitigating the risk that past and future issues will potentially occur. This is even more important with the automobile designs of today and for those in the future, specifically the hybrid and fuel cell vehicle. DFMEA and FTA are tools that aid in the understanding of complex design risks, from the system level down to the component level. This session will look at different case studies (from simple to complex) and the strategies used to understand systemic failure modes using both DFMEA and FTA.

Fuel economy and stringent emissions requirements have steered the automotive industry to invest in advanced propulsion hybrids, including Plug-in hybrid vehicles (PHEV) and Fuel cell vehicles. The choice of battery technology, its power and thermal management and the overall vehicle energy optimization during different conditions are crucial design considerations for PHEVs and battery electric vehicles (BEV). Current industry focus is on Li-Ion batteries due to their high energy density. However, extreme operating temperatures may impact battery life and performance. Different cooling strategies have been proposed for efficient thermal management of battery systems. This paper discusses the modeling and analysis strategy for a thermally managed Lithium Ion (Li-Ion) battery pack, with coolant as the conditioning medium.

The fifth generation of General Motor's “Small Block” 90-degree V engine family has been developed with a totally new combustion system. This system employs direct fuel injection (DI) and carefully architected in-cylinder flow field development in order to significantly improve all aspects of combustion system performance. Efficiency improvements stem from increased compression ratio, greatly improved dilution tolerance, and excellent knock resistance. The asymmetric, 2-valve (2V) layout of the “Small Block” engine presented unique challenges in developing the combustion system, but also offered unusual opportunities for an elegant solution while retaining the traditional “Small Block” attributes of packaging efficiency and power density.

Rubber isolators and bushings are very important components for vehicle performance. However, one often finds it is difficult to get the dynamic properties to be readily used in CAE analysis, either from suppliers or from OEM's own test labs. In this paper, the author provides an analytical method to obtain the dynamic stiffness of an exhaust isolator, using ABAQUS and iSight, with tested or targeted isolator static stiffness information. The analysis contains two steps. The first step is to select the (rubber/EPDM) material properties for the FE isolator model by matching the static stiffness with either the targeted spring rate (linear or nonlinear) or the (tested) load / deflection curve. The second step is to perform dynamic analysis on the statically “validated” FE isolator model to obtain its dynamic properties.

The initial presence and dynamic formation of internal voids in human body models have been subjects of discussion within the human body modeling community. The relevant physics of the human body are described and the importance of capturing this physics for modeling of internal organ interactions is demonstrated. Basic modeling concepts are discussed along with a proposal of simulation setups designed to verify model behavior in terms of volume and pressure between internal organs.

With reference to present literature, most OEMs are working on reducing product development time by around ~20%, through seamless integration of digital ecosystem and focusing on dynamic customer needs. The Systems Engineering approach focuses on functions & systems rather than components. In this approach, designers (Computer Aided Design) / analysts (Computer Aided Engineering) need to understand program requirements early to enable seamless integration. This approach also reduces the number of iterative loops between cross functions thereby reducing the development cycle time. In this paper, we have attempted to tackle a common challenge faced by Closures (Liftgate) engineering: meeting slam durability fatigue life while replicating customer normal and abusive closing behavior.

In a parallel hybrid electric vehicle, higher fuel economy gains are typically achieved if significant electric drive (or engine-off) operation is possible, shifting the engine operating schedule so that it only runs at medium to high load for best efficiency. To enable efficient engine-off driving, a typical configuration will have a disconnect clutch between the engine and the rest of the driveline. In some configurations, when engine-on operation is requested the disconnect clutch is applied in conjunction with the traction motor/generator to crank the engine (i.e., a flying engine start). In this paper we describe the development of a control system for a flying engine start using an engine disconnect clutch. The clutch is located between the engine and electric motor, which is connected to the input of a multispeed transmission. We first describe an initial control algorithm evaluation using a driveline model.

Carbon Nanotube (CNT) thin film speakers produce sound with the thermoacoustic effect. Alternating current passes through the low heat capacity CNT thin film changing the surface temperature rapidly. CNT thin film does not vibrate; instead it heats and cools the air adjacent to the film, creating sound pressure waves. These speakers are inexpensive, transparent, stretchable, flexible, magnet-free, and lightweight. Because of their novelty, developing a model and better understanding the performance of CNT speakers is useful in technology development in applications that require ultra-lightweight sub-systems. The automotive industry is a prime example of where these speakers can be enabling technology for innovative new component design. Developing a multi-physics (Electrical-Thermal-Acoustical) FEA model, for planar CNT speakers is studied in this paper. The temperature variation on the CNT thin film is obtained by applying alternating electrical current to the CNT film.

Future lunar missions will utilize a Lunar DC microgrid (LDCMG) to construct the infrastructure for distributing, storing, and utilizing electrical energy. The LDCMG’s energy management, of which energy storage systems (ESS) are crucial components, will be essential to the success of the missions. Standard system design currently employs a rule-of-thumb approach in which design methodologies rely on heuristics that may only evaluate local power balancing requirements. The Hamiltonian surface shaping and power flow control (HSSPFC) method can also be utilized to analyze and design the lunar LDCMG power distribution network and ESS. In this research, the HSSPFC method will be utilized to determine the ideal energy storage requirements for ESS and the optimally distributed control architecture.

The GD₃ or GD Cubed method of problem prevention has been applied to product changes and to test results at the component, subsystem and vehicle level. GD₃ stands for Good Design - Good Discussion - Good Dissection. Good Discussion of changes (Design Review Based on Failure Mode) identifies BUDS of PROBLEMS that may arise from interfaces and areas of change. Good Dissection (Design Review Based on Test Results) is applied to physical test samples during and after tests to identify Buds of Problems that may not be obvious from inspection of the parts or test results. The paper first describes implementation of the GD₃ principles and methods supporting Good Discussion (DRBFM) and Good Dissection, and then discusses how they are applied and embedded in the Vehicle Development Process at General Motors Co.

Eco Approach and Departure (Eco-AnD) is a Connected Automated Vehicle (CAV) technology aiming to reduce energy consumption for crossing a signalized intersection or set of intersections in a corridor that features vehicle-to-infrastructure (V2I) communication capability. This research focuses on developing a Dynamic Programming (DP) based algorithm for a PHEV operating in Charge Depleting mode. The algorithm used the Reduced Order Energy Model (ROM) to capture the vehicle powertrain characteristics and road grade to capture the road dynamics. The simulation results are presented for a real-world intersection and 20-25% energy benefits are shown by comparing against a simulated human driver speed profile. The vehicle-level validation of the developed algorithm is carried out by performing closed-course track testing of the optimized speed solutions on a real CAV vehicle.

The AutoDrive Challenge competition sponsored by General Motors and SAE gives undergraduate and graduate students an opportunity to get hands-on experience with autonomous vehicle technology and development as they work towards their degree. Michigan Technological University has participated in the AutoDrive Challenge since its inception in 2017 with students participating through MTU’s Robotic System Enterprise. The MathWorks Simulation Challenge has been a component of the competition since its second year, tasking students with the development of perception, control and testing algorithms using MathWorks software products. This paper presents the pedagogical approach graduate student mentors used to enable students to build their understanding of autonomous vehicle concepts using familiar tools. This approach gives undergraduate students a productive experience with these systems that they may not have encountered in coursework within their academic program.

This research investigates the energy savings achieved through eco-driving controls in connected and automated vehicles (CAVs), with a specific focus on the influence of powertrain characteristics. Eco-driving strategies have emerged as a promising approach to enhance efficiency and reduce environmental impact in CAVs. However, uncertainty remains about how the optimal strategy developed for a specific CAV applies to CAVs with different powertrain technologies, particularly concerning energy aspects. To address this gap, on-track demonstrations were conducted using a Chrysler Pacifica CAV equipped with an internal combustion engine (ICE), advanced sensors, and vehicle-to-infrastructure (V2I) communication systems, compared with another CAV, a previously studied Chevrolet Bolt electric vehicle (EV) equipped with an electric motor and battery.

Predictive Signal Phase and Timing (SPAT) message set is one fundamental building block for vehicle-to-infrastructure (V2I) applications such as Eco-Approach and Departure (EAD) at traffic signal controlled urban intersections. Among the two complementary communication methods namely short-range sidelink (PC5) and long-range cellular radio link (Uu), this paper documents the work with long-range link: the complete data chain includes connecting to the traffic signals via existing backhaul communication network, collecting the raw signal phase state data, predicting the signal state changes and delivering the SPAT data via a geofenced service to requests over HTTP protocols. An Application Programming Interface (API) library is developed to support various cellular data transmission reduction and latency improvement techniques.

A 2-D computational model was developed to describe the flow and filtration processes, in a honeycomb structured ceramic diesel particulate trap. This model describes the steady state trap loading, as well as the transient behavior of the flow and filtration processes. The theoretical model includes the effect of a copper fuel additive on trap loading and transient operation. The convective terms were based on a 2-D analytical flow field solution derived from the conservation of mass and momentum equations. The filtration theory incorporated in the time dependent numerical code included the diffusion, inertia, and direct interception mechanisms. Based on a measured upstream particle size distribution, using the filtration theory, the downstream particle size distribution was calculated. The theoretical filtration efficiency, based on particle size distribution, agreed very well (within 1%) with experimental data for a number of different cases.