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Prior work with the concept of dividing the exhaust process into an early and late phase has shown the potential of applying only the early stage (blow-down) of the exhaust period directly to a turbocharger or turbocharger system, and the later stage (scavenge) arranged to bypass the turbine. In this manner, the exhaust backpressure required to extract high turbine work from the engine can be isolated from the displacement phase of the exhaust stroke and thereby greatly reduce the exhaust pumping work and Residual Gas Fraction. In previously-published efforts, the challenges of valve-event control and high turbine inlet temperature have been revealed. The BorgWarner Engine Systems Group, in conjunction with Presta, has applied a cam-phaser controlled concentric camshaft system to the exhaust side of a divided exhaust port 4-valve per cylinder DOHC GDI engine, to enable variable phasing between the Blow-down and Scavenge cam profiles.

As CO2 legislation tightens, the next generation of turbocharged gasoline engines must meet stricter emissions targets combined with increased fuel efficiency standards. Recent studies have shown that the following technologies offer significant improvements to the efficiency of turbocharged GDI engines: Miller Cycle via late intake valve closing (LIVC), low pressure loop cooled EGR (LPL EGR), port water injection (PWI), and cylinder deactivation (CDA). While these efficiency-improving technologies are individually well-understood, in this study we directly compare these technologies to each other on the same engine at a range of operating conditions and over a range of compression ratios (CR). The technologies tested are applied to a boosted and direct injected (DI) gasoline engine and evaluated both individually and combined.

As CO2 legislation tightens, the next generation of turbocharged gasoline engines must meet stricter emissions targets combined with increased fuel efficiency standards. Promising technologies under consideration are: Miller Cycle via late intake valve closing (LIVC), low pressure loop cooled exhaust gas recirculation (LPL EGR), port water injection (PWI), and cylinder deactivation (CDA). While these efficiency improving options are well-understood individually, in this study we directly compare them to each other on the same engine at a range of operating conditions and over a range of compression ratios (CR). For this purpose we undertake a comprehensive simulation of the above technology options using a GT-Power model of the engine with a kinetics based knock combustion sub-model to optimize the fuel efficiency, taking into account the total in-cylinder dilution effects, due to internal and external EGR, on the combustion.

Wound rotor synchronous machines (WRSM) without rare-earth magnets are becoming more popular for traction applications, but their potential in drive performance has not yet been fully explored. This paper presents a Pulse Width Modulation (PWM) scheme optimization procedure to minimize motor and inverter losses. It leverages different PWM schemes with different PWM switching strategies and switching frequencies. First, a generic PWM-induced motor loss calculation tool developed by BorgWarner is introduced. This tool iteratively calculates motor losses with PWM inputs across the entire operating map, significantly improving motor loss prediction accuracy. The inverter losses are then calculated analytically using motor and wide-bandgap (WBG) switching device characteristics. By quantifying these various scenarios, the optimal PWM scheme for achieving the best system efficiency across the entire operating map is obtained.

This paper gives a thorough review of the HC/CO emissions challenge and discusses the effects of different diesel oxidation catalyst designs in a pre turbine and post turbine position on steady state and transient turbo charger performance as well as on HC and CO tailpipe emissions, fuel economy and performance of modern Diesel engines. Results from engine dynamometer testing are presented. Both classical diffusive and advanced premixed Diesel combustion modes are investigated to understand the various effects of possible future engine calibration strategies.

Diesel engines nowadays are faced with enhanced emission standards, which limit further improvements in fuel economy. In order to meet future emission regulations in a cost effective way, high levels of EGR are needed. One way of increasing the level of EGR with current technology boosting systems is to utilize low pressure loop EGR. This paper discusses the benefits of low pressure loop EGR as well as some of the challenges. A new component is presented which overcomes some of these challenges. Also, modifications to current technology compressor wheels are presented which enable the compressor wheel to survive ingestion of exhaust gas.

Considering the current trend towards the electrification of commercial vehicles, the development of Beam eAxle solutions has become necessary. The utilization of an electric drive unit in heavy-duty solid axle-based commercial vehicles presents unique and demanding challenges. These include the necessity for elevated peak and continuous torque while meeting packaging constraints, structural integrity requirements, and extended service life. One such solution was developed by BorgWarner to address these challenges. This paper offers a comprehensive overview of the design and development process undertaken for this Dual Motor Beam eAxle system. This includes the initial comparison of various eAxle solutions, the specifications of components selected for this design, and the initial results from dyno and vehicle development.

The design of a demonstration vehicle is presented where improvements to the electrical and air induction systems are made which provide increased performance with improved fuel economy. This is made possible by a 48 V architecture which enables the deployment of new components, specifically a belted motor generator unit (MGU) and electrically-driven compressor (eBooster®). The synergy between these components enables energy efficient means to collect regenerated energy and provide added torque, faster engine response, and extended engine off operation among a list of added features. Control features and strategy are highlighted along with simulation and vehicle test data. Resultant performance and fuel economy benefits are reviewed which support the contention of 48 V being a cost effective architecture to enable CO2 reduction relative to a higher voltage hybrid.

This reference contains the latest knowledge on vehicle development with CVT powertrains, transmission assembly design and performance, and the design and development of the five major components of CVT technology: launch device, variator systems, geartrains, control systems, and lubrication. Building on an earlier SAE publication, the 37 technical papers selected for this book cover updated information on a variety of topics within the area of CVTs. Although this book is not intended to represent the full body of CVT technology, it provides technical presentations and their reference documents, which can lead to discussions covering several topics of interest in CVTs.

Cooled LPL EGR is a proven means of improving the efficiency of a Gasoline Turbocharged Direct-Injection engine. One of the most significant hurdles to overcome in implementing a LPL EGR system is dealing with condensation of water near the entrance of the turbocharger's compressor wheel. A gasoline engine, and to a greater extent a spark ignition engine running on Natural Gas, will encounter enough water condensation at some steady-state conditions to damage the compressor wheel due to the high-speed collision between the compressor blades and the water droplets. As an alternative to not utilizing beneficial EGR at the condensing conditions, the team at BorgWarner have developed a LPL EGR mixer that is effective at condensing and collecting the water droplets and routing the water around the compressor wheel. The new Condensing EGR mixer was developed from the known concept of utilizing a mild venturi section to enhance EGR delivery and mixing.

Accelerated adoption of electric propulsion system in mobility industry has stressed the time and iterations of product development cycle which was traditionally known to go over multiple iterations and phases. Current market demands a timely introduction of compelling products that brings high value to end user. Further, a growing emphasis over reducing mineral content using sustainable options and process, adds further complexity to multi-objective-optimization of electric drive systems. At BorgWarner our engineers use Digital-Twins, physics-based models which closely represent BorgWarner products in greater dept (physics) thus allowing an improved assessment of product design (components and systems) to target application at very early stage in product development. The spring success with Digital-Twin, BorgWarner furthered enhanced the model through introducing Artificial Intelligent (AI) and Machine Learning (ML) technologies in both modelling and virtual sensing.

Trying to improve the modern diesel engine's NOx/soot tradeoff without giving up fuel economy continues to be a core target for the engine development community. One of the options not yet fully investigated for the diesel is applying variable valve events to the engine breathing process. Already used in some heavy-duty applications, late intake valve closing has long been regarded as a possible strategy for small diesel engines. Single-cylinder tests applying fully variable valve events have demonstrated potential but also raised doubts about VVA benefits on automotive size diesel engines. Full engine testing using realistic valve train technology is seen as key to judging its true performance because it covers not only combustion benefits but also influences like engine pumping on emissions and CO₂. Different to past publications, this paper focuses on testing a production feasible variable valve train technology on a fully instrumented modern Common Rail diesel engine.

A 1-D GT-Power model based investigation has been carried out to identify the impact of late intake valve closing (LIVC) on fuel economy and emission reduction of a modern small bore diesel engine. The diesel engine examined employed a variable turbine geometry (VTG) turbocharger with air-to-air charge cooler, cooled low pressure exhaust gas re-circulation (LP-EGR), and cooled high pressure exhaust gas re-circulation (HP-EGR). The LIVC system investigated varied the closing time of the intake valve by increasing or decreasing the dwell at the maximum valve lift point. This paper describes how the fuel economy and NOx emission of the diesel engine were affected by varying the intake valve closing time. The intake valve closing time was delayed by as much as 60 degrees.

The paper presents the structure of an air system controller and its application to a modern boosted dual loop EGR Diesel engine. Results over a U.S. FTP cycle which show improvements in emissions and fuel consumption with future opportunities for increased performance are discussed. A recent application of the controller is also shown where standard engine sensors are eliminated to reduce cost and their function is replaced with in-cylinder pressure measurement combined with signal processing techniques.

The paper presents a thermal management development capability and approach that was put in place to understand the relative benefit of various thermal components, layouts and control strategies. The use of the approach on a modern diesel powered vehicle is given. Thermal performance along with associated fuel economy improvements are shown over various test cycles including the FTP and US06. Results are given for a GT-Suite simulation as well as on vehicle.

The paper presents the results of applying an advanced thermal management approach to a light duty commercial vehicle. The relative benefit of various thermal components, layouts and control strategies is discussed. Thermal performance along with associated fuel economy improvements are shown over various test cycles including the FTP, NEDC and US06. Results are given for a GT-Suite simulation as well as on vehicle.

A GT-suite commercial code was used to develop a fully integrated model of a light duty commercial vehicle with a V6 diesel engine, to study the use of a BorgWarner dual mode coolant pump (DMCP) in active thermal management of the vehicle. An Urban Dynamometer Driving Schedule (UDDS) was used to validate the simulation results with the experimental data. The conventional mechanical pump from the validated model was then replaced with the dual mode coolant pump. The control algorithm for the pump was based on controlling the coolant temperature with pump speed. Maximum electrical speed of the pump and the efficiency of the pump were used to determine whether the pump should run in mechanical or electrical mode. The model with the dual mode coolant pump was simulated for the UDDS cycle to demonstrate the effectiveness of control strategy.

There are many methods developed over the past decade to solve the problem of energy management control for hybrid electric vehicles. A novel method is introduced in this paper to address the same problem which reduces the problem to a set of physical equations and maps. In simple terms, this method directly calculates the actual cost or savings in fuel energy from the generation or usage of electric energy. It also calculates the local optimum electric power that yields higher electric fuel savings (EFS) or lower electric fuel cost (EFC) in the fuel energy that is spent for driving the vehicle (which in general does not take the system to the lowest engine Brake Specific Fuel Consumption (BSFC)). Based on this approach, a control algorithm is developed which attempts to approach the global optimum over a drive cycle.