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This paper describes a configuration and controller, designed using Autonomie,1 for dual-motor battery electric vehicle (BEV) heavy-duty trucks. Based on the literature and current market research, this model was designed with two electric motors, one on the front axle and the other on the rear axle. A rule-based control algorithm was designed for the new dual-motor BEV, based on the model, and the control parameters were optimized by using a genetic algorithm (GA). The model was simulated in diverse driving cycles and gradeability tests. The results show both a good following of the desired cycle and achievement of truck gradeability performance requirements. The simulation results were compared with those of a single-motor BEV and showed reduced energy consumption with the high-efficiency operation of the two motors.

In-cylinder surface temperature is of heightened importance for Homogeneous Charge Compression Ignition (HCCI) combustion since the combustion mechanism is thermo-kinetically driven. Thermal Barrier Coatings (TBCs) selectively manipulate the in-cylinder surface temperature, providing an avenue for improving thermal and combustion efficiency. A surface temperature swing during combustion/expansion reduces heat transfer losses, leading to more complete combustion and reduced emissions. At the same time, achieving a highly dynamic response sidesteps preheating of charge during intake and eliminates the volumetric efficiency penalty. The magnitude and temporal profile of the dynamic surface temperature swing is affected by the TBC material properties, thickness, morphology, engine speed, and heat flux from the combustion process. This study follows prior work of authors with Yttria Stabilized Zirconia, which systematically engineered coatings for HCCI combustion.

Thermal barrier coatings with low conductivity and low heat capacity have been shown to improve the performance of homogeneous charge compression ignition (HCCI) engines. These coatings improve the combustion process by reducing heat transfer during the hot portion of the engine cycle without the penalty thicker coatings typically have on volumetric efficiency. Computational fluid dynamic simulations with conjugate heat transfer between the in-cylinder fluid and solid piston of a single cylinder HCCI engine with exhaust valve rebreathing are carried out to further understand the impacts of these coatings on the combustion process. For the HCCI engine studied with exhaust valve rebreathing, it is shown that simulations needed to be run for multiple engine cycles for the results to converge given how sensitive the rebreathing process is to the residual gas state.

The Organic Rankine Cycle (ORC) has proven to be a promising technology for Waste Heat Recovery (WHR) systems in heavy duty diesel engine applications. However, due to the highly transient heat source, controlling the working fluid flow through the ORC system is a challenge for real time application. With advanced knowledge of the heat source dynamics, there is potential to enhance power optimization from the WHR system through predictive optimal control. This paper proposes a look-ahead control strategy to explore the potential of increased power recovery from a simulated WHR system. In the look-ahead control, the future vehicle speed is predicted utilizing road topography and V2V connectivity. The forecasted vehicle speed is utilized to predict the engine speed and torque, which facilitates estimation of the engine exhaust conditions used in the ORC control model.

The current work studies the reliability of a solenoid valve (SV) used in automobile transmissions through a joint theoretical and experimental approach. The goal of this work is to use accelerated tests to characterize SV failure and correlate the results to new comprehensive finite element models (Part 1). A custom test apparatus has been designed and built to simultaneously monitor and actuate up to four SVs. The test apparatus is capable of applying a controlled duty cycle, current and actuation frequency. The SVs are also placed in a thermal chamber so that the ambient temperature can be controlled precisely. The apparatus measures in real-time the temperature, current, and voltage of each SV. A series of tests have been conducted to produce repeated failures of the SV. The failure of the SV appears to be caused by overheating and failure of the insulation used in the solenoid coil.

A comprehensive multi-physics theoretical model of the solenoid valve used in an automobile transmission is constructed using the finite element method. The multi-physics model includes the coupled effects of electromagnetic, thermodynamics and solid mechanics. The resulting finite element model of the solenoid valve provides useful information on the temperature distribution, mechanical and thermal deformations, and stresses. The model results predict that the solenoid valve is susceptible to a coupled electrical-thermo-mechanical failure mechanism. The coil can generate heat which can cause compressive stress and high temperatures that in turn could fail the insulation between the coil wires. The model facilitates the characterization of the solenoid valve performance, life and reliability and can be used as a predictive tool in future solenoid design.

The application of hydrogen (H2) as an internal combustion (IC) engine fuel has been under investigation for several decades. The favorable physical properties of hydrogen make it an excellent alternative fuel for IC engines and hence it is widely regarded as the energy carrier of the future. Direct injection of hydrogen allows optimizing this potential as it provides multiple degrees of freedom to influence the in-cylinder combustion processes and consequently engine efficiency and exhaust emissions. At certain operating conditions the stratification associated with hydrogen direct injection (DI) leads to an efficiency improvement. However, it also results in higher emissions levels. This paper examines the effects of combining an advanced direct injection strategy with water injection for efficiency benefits and emissions reduction of a hydrogen fuelled DI spark ignition (SI) engine.

At 70 miles per hour, overcoming aerodynamic drag represents about 65% of the total energy expenditure for a typical heavy truck vehicle. The goal of this US Department of Energy supported consortium is to establish a clear understanding of the drag producing flow phenomena. This is being accomplished through joint experiments and computations, leading to the intelligent design of drag reducing devices. This paper will describe our objective and approach, provide an overview of our efforts and accomplishments related to drag reduction devices, and offer a brief discussion of our future direction.

Structure borne sound is one of the most important reasons of noise pollution in the automobiles and aircraft's. Noise is mostly generated by the vibrating panels excited by either a mechanical or an acoustical excitation. Examples of the typical vibrating structures in automobiles are engine cylinder, gearbox cover, transmission system covers, panels of the body etc. Sound radiation characteristics are also important in the phenomenon of resonant sound transmission through a panel. Resonant sound transmission occurs because of resonant modes of the panel within the frequency bandwidth of interest. Typical example of resonant sound transmission is the transmission through a firewall of an automobile, which forms the partition between the engine compartment and the cabin interior. Radiation characteristics can be typically defined by radiated sound power, radiation efficiency and space average mean square velocity of the panel.