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The tightening emissions regulations across the globe pose significant challenges to vehicle OEMs. As a result, OEMs are diversifying their powertrain solutions e.g., CNG/Propane based conventional powertrains, BEVs, H2 ICE, FCEV, etc. to meet these regulations. More recently, the ‘CARB Advanced Clean Trucks’ and ‘EPA GHG Phase 3’ regulations are forcing manufacturers to increasingly adopt zero tailpipe emission solutions. While passenger vehicle applications are trending towards a single consensus i.e., BEVs, the heavy-duty on-road applications are challenged with unique requirements of high payload capacity, higher range, lower sales volumes, higher durability, short refueling time, etc. These requirements are driving manufacturers to consider FCEV as an alternative powertrain solution to BEV specifically for higher payload capacity, and range applications.

The Environmental Protection Agency (EPA) and California Air Resources Board (CARB) have recently announced rulemakings focused on tighter emission limits for oxides of nitrogen (NOx) from heavy-duty trucks. As part of the new rulemaking CARB has proposed a Low Load Cycle (LLC) to specifically evaluate NOx emission performance over real-world urban and vocational operation typically characterized by low engine loads, thereby demanding the implementation of continuous active thermal management of the engine and aftertreatment system. This significant drop in NOx levels along with continued reduction in the Green House Gas (GHG) limits poses a more significant challenge for the engine developer as the conventional emission reduction approaches for one species will likely result in an undesirable increase in the other species.

The automotive industry continues to develop new powertrain and vehicle technologies aimed at reducing overall vehicle-level fuel consumption. Specifically, the use of electrified propulsion systems, including electrified and electric drive units (EDU), is expected to play a significant role in helping OEMs meet fleet CO2 reduction targets for 2025 and beyond. The change to vehicles propelled by electrified powertrains leads to a reduction in vehicle noise levels. Despite the overall noise levels being low, the NVH behavior of such vehicles can be objectionable due to the presence of tonal noise coming from electric machines and geartrain components. In order to ensure customer acceptance of electrically propelled vehicles, it is imperative that these NVH challenges are understood and solved. Specifically, this paper discusses the EDU NVH development process. This includes considerations for CAE/test-based development and validation processes to ensure optimal NVH development.

The automotive industry continues to develop new powertrain and vehicle technologies aimed at reducing overall vehicle-level fuel consumption. Specifically, the use of electrified propulsion systems is expected to play an increasingly important role in helping OEM’s meet fleet CO2 reduction targets for 2025 and beyond. This will also include a strong growth in the global demand for electric drive units (EDUs). The change from conventional vehicles to vehicles propelled by EDUs leads to a reduction in overall vehicle exterior and interior noise levels, especially during low-speed vehicle operation. Despite the overall noise levels being low, the NVH behavior of such vehicles can be objectionable due to the presence of tonal noise coming from electric machines and geartrain components as well as relatively high shares of road/wind noise. In order to ensure customer acceptance of electrically propelled vehicles, it is imperative that these NVH challenges are understood and solved.

A novel approach to the Integration of Turbocompounding/WHR, Electrification and Supercharging technologies (ITES) to reduce fuel consumption in a medium heavy-duty diesel engine was previously published by FEV. This paper describes a modified approach to ITES to reduce fuel consumption on a heavy-duty diesel engine applied in a Class 8 tractor. The original implementation of the ITES incorporated a turbocompound turbine as the means for waste heat recovery. In this new approach, the turbocompound unit connected to the sun gear of the planetary gear set has been replaced by an organic Rankine cycle (ORC) turbine expander. The secondary compressor and the electric motor-generator are connected to the ring gear and the carrier gear respectively. The ITES unit is equipped with dry clutch and band brake allowing flexibility in mechanical and electrical integration of the ORC expander, secondary compressor and electric motor-generator to the engine.

Automatic engine start/stop systems are becoming more prevalent and increasing market share of these systems is predicted due to demands on improving fuel efficiency of vehicles. Integration of an engine start/stop system into a “conventional” drivetrain with internal combustion engine and 12V board system is a relatively cost effective measure to reduce fuel consumption. Comfort and NVH aspects will continue to play an important role for customer acceptance of these systems. Possible delay during vehicle launch due to the engine re-start is not only a safety relevant issue but a hesitating launch feel characteristic will result in reduced customer acceptance of these systems. The engine stop and re-start behavior should be imperceptible to the driver from both a tactile and acoustic standpoint. The lack of masking effects of the engine during the engine stop phases can cause other “unwanted” noise to become noticeable or more prominent.

The interest in electric propulsion of vehicles has increased in recent years and is being discussed extensively by experts as well as the public. Up to now the driving range and the utilization of pure electric vehicles are still limited in comparison to conventional vehicles due to the limited capacity and the long charging times of today's batteries. This is a challenge to customer acceptance of a pure electric vehicle, even for a city car application. A Range Extender concept could achieve the desired customer acceptance, but should not impact the “electric driving” experience, and should not cause further significant increases in the manufacturing and purchasing cost. The V2 engine concept presented in this paper is particularly suited to a low cost, modular vehicle concept. Advantages regarding packaging can be realized with the use of two generators in combination with the V2 engine.

Since the 1990's regulatory requirements for On-Board-Diagnostics (OBD) have continuously evolved with an increasing application of advanced electronics and control systems that have been adopted for automotive applications. The current and future demands on emissions and performance requirements are pushing the envelope with respect to management of complex control software strategies, hardware components and their interactions. This further challenges the implementation of OBD. In order to build a robust monitor for a complex system which has minimum risk of false detection, a thorough understanding of both system and components is required. In this paper, several methods will be presented that can be utilized to achieve a successful and robust diagnostic system implementation. Implementation begins with a discussion of the major challenges to achieve consistent performance in the base system control.

The growing complexity of powertrain control strategies, software, and hardware is proving to be a significant challenge to the engineering community with regard to managing effective optimization to meet the desired performance. With an increased emphasis on shorter development time and the use of additional sensors and actuators becoming common, the increased dependence on physical models and use of complex interdependent control systems demands a thorough system understanding. This also encourages the use of process improvement tools to assist in an effective engineering process. In this paper, such a tool is discussed in its second phase of development. The Micro-HiL system will be discussed over a wide scope that focuses on the interests of the calibration and development community. The purpose of this paper is to provide an update on the Phase 2 activity of Micro-HiL development; Phase 1 was discussed in-depth at the 2011 SAE World Congress [2011-01-0703].

Beginning in 2010, implementation of on-board diagnostics (OBD) is mandatory for all the heavy-duty engine applications in the United States. The task of developing OBD strategies and calibrating them is a challenging one. The process involves a strong interdependency on base engine emissions, controls and regulations. On top of that the strategies developed as a result of the regulatory requirements need to go through a stringent and time-intensive process of software implementation and integration. The recent increasing demands to minimize the development process have been pushing the envelope on the methodologies used in developing the strategies and the calibration for robust monitoring. The goal of this paper is to provide a concise overview of a process utilized to help the development, testing and calibration of the OBD strategies on a 2010 model year heavy-duty diesel engine.

Raising interest in Diesel powered passenger cars in the United States in combination with the government mandated policy to reduce dependency of foreign oil, leads to the desire of operating Diesel vehicles with Biodiesel fuel blends. There is only limited information related to the impact of Biodiesel fuels on the performance of advanced emission control systems. In this project the implementation of a NOx storage and a SCR emission control system and the development for optimal performance are evaluated. The main focus remains on the discussion of the differences between the fuels which is done for the development as well as useful life aged components. From emission control standpoint only marginal effects could be observed as a result of the Biodiesel operation. The NOx storage catalyst results showed lower tailpipe emissions which were attributed to the lower exhaust temperature profile during the test cycle. The SCR catalyst tailpipe results were fuel neutral.

Due to raising interest in diesel powered passenger cars in the U.S. in combination with a desire to reduce dependency on imported petroleum, there has been increased attention to the operation of diesel vehicles on fuels blended with biodiesel. One of several factors to be considered when operating a vehicle on biodiesel blends is understanding the impact and performance of the fuel on the emission control system. This paper documents the impact of the biodiesel blends on engine-out emissions as well as the overall system performance in terms of emission control system calibration and the overall system efficiency. The testing platform is a light-duty HSDI diesel engine with a Euro 4 base calibration in a 1700 kg sedan vehicle. It employs 2nd generation common-rail injection system with peak pressure of 1600 bar as well as cooled high-pressure EGR. The study includes 3 different fuels (U.S.

In order to allow continued production of the AM General Optimizer 6500 during MY 2007 through 2010 this IDI engine (Indirect Injection - swirl chamber) requires sophisticated aftertreatment controls while maintaining its fuel economy and durability. The main purpose of the development program was to retain the relatively inexpensive and simple base engine with distributor pump and waste-gated turbocharger, while adding hardware and software components that allow achievement of the phase-in emission standards for 2007 through 2010. The aftertreatment system consists of Diesel Oxidation Catalyst (DOC), NOx Adsorber Catalyst (or DeNOx Trap - DNT) and Diesel Particle Filter (DPF). In addition to the base hardware, an intake air throttle valve and an in-exhaust fuel injector were installed. The presented work will document the development process for a 2004 certified 6.5 l IDI heavy-duty diesel engine to comply with the 2007 heavy-duty emission standards.

The U.S. Tier 2 emission regulations require sophisticated exhaust aftertreatment technologies for diesel engines. One of the projects under the U.S. Department of Energy's (DOE's) Advanced Petroleum Based Fuels - Diesel Emission Controls (APBF-DEC) activity focused on the development of a light-duty passenger car with an integrated NOx (oxides of nitrogen) adsorber catalyst (NAC) and diesel particle filter (DPF) technology. Vehicle emissions tests on this platform showed the great potential of the system, achieving the Tier 2 Bin 5 emission standards with new, but degreened emission control systems. The platform development and control strategies for this project were presented in 2004-01-0581 [1]. The main disadvantage of the NOx adsorber technology is its susceptibility to sulfur poisoning. The fuel- and lubrication oil-borne sulfur is converted into sulfur dioxide (SO2) in the combustion process and is adsorbed by the active sites of the NAC.

Increasing fuel costs, the need to reduce dependence on foreign oil as well as the high efficiency and the desire for superior durability have caused the diesel engine to again become a prime target for light-duty vehicle applications in the United States. In support of this the U.S. Department of Energy (DOE) has engaged in a test project under the Advanced Petroleum Based Fuels-Diesel Emission Control (APBF-DEC) activity to develop a passenger car with the capability to demonstrate compliance with Tier 2 Bin 5 emission targets with a fresh emission control catalyst system. In order to achieve this goal, a prototype engine was installed in a passenger car and optimized to provide the lowest practical level of engine-out emissions.