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A simulation framework with a validated system model capable of estimating fuel consumption is a valuable tool in analysis and design of the hybrid vehicles. In particular, the framework can be used for (1) benchmarking the fuel economy achievable from alternate hybrid powertrain technologies, (2) investigating sensitivity of fuel savings with respect to design parameters (for example, component sizing), and (3) evaluating the performance of various supervisory control algorithms for energy management. Presenter Chinmaya Patil, Eaton Corporation

An advanced exhaust aftertreatment system is characterized following end-of-life catalyst aging to meet final Tier 4 off-highway emission requirements. This system consists of a fuel dosing system, mixing elements, fuel reformer, lean NOx trap (LNT), diesel particulate filter (DPF), and a selective catalytic reduction (SCR) catalyst. The fuel reformer is used to generate hydrogen (H2) and carbon monoxide (CO) from injected diesel fuel. These reductants are used to regenerate and desulfate the LNT catalyst. NOx emissions are reduced using the combination of the LNT and SCR catalysts. During LNT regeneration, ammonia (NH3) is intentionally released from the LNT and stored on the downstream SCR catalyst to further reduce NOx that passed through the LNT catalyst. This paper addresses system durability as the catalysts were aged to 500 desulfation events using an off-highway diesel engine.

Diesel exhaust aftertreatment systems are required for meeting both EPA 2010 and final Tier 4 emission regulations. This paper addresses aftertreatment system performance of a fuel reformer, lean NOx trap (LNT) and selective catalytic reduction (SCR) system designed to meet the EPA 2010 emission standards for an on-highway heavy-duty vehicle. The aftertreatment system consists of a fuel dosing system, mixing elements, fuel reformer, LNT, diesel particulate filter (DPF), and SCR for meeting NOx and particulate emissions. System performance was characterized in an engine dynamometer test cell, using a development, 13L, heavy-duty engine. The catalyst performance was evaluated using degreened catalysts. Test results show that system performance met the EPA 2010 emission standards under a range of test conditions that were reflective of actual vehicle operation.

Diesel Cylinder Deactivation (CDA) has been shown in previous work to increase exhaust temperatures, improve fuel efficiency, and reduce engine-out NOx for engine loads up to 3 bar BMEP. The purpose of this study is to determine whether or not the turbocharger needs to be altered when implementing CDA on a diesel engine. This study investigates the effect of CDA on exhaust temperature, fuel efficiency, and turbocharger performance in a 15L heavy-duty diesel engine under low-load (0-3 bar BMEP) steady-state operating conditions. Two calibration strategies were evaluated. First, a “stay-hot” thermal management strategy in which CDA was used to increase exhaust temperature and reduce fuel consumption. Next, a “get-hot” strategy where CDA and elevated idle speed was used to increase exhaust temperature and exhaust enthalpy for rapid aftertreatment warm-up.

Sintered valve guides are increasingly used in various engine applications due to their superior durability and cost. Typical valve guide materials are low alloyed materials of the type Fe-Cu-C. More severe applications may require higher alloying content. One such application is EGR where the exhaust temperatures are much higher as compared to the conventional automotive valve guide. A new material was developed to work in this harsh environment. The object of this paper is to report development of this material including material properties and durability test results.

An LNT + SCR diesel aftertreatment system was developed in order to meet the 2010 US HD EPA on-road, and tier 4 US HD EPA off-road emission standards. This system consists of a fuel reformer (REF), lean NOx trap (LNT), catalyzed diesel particulate filter (DPF), and selective catalytic reduction (SCR) catalyst arranged in series to reduce tailpipe nitrogen oxides (NOx) and particulate matter (PM). This system utilizes a REF to produce hydrogen (H2), carbon monoxide (CO) and heat to regenerate the LNT, desulfate the LNT, and actively regenerate the DPF. The NOx stored on the LNT is reduced by the H2 and CO generated in the REF converting it to nitrogen (N2) and ammonia (NH3). NH3, which is normally an undesired byproduct of LNT regeneration, is stored in the downstream SCR which is utilized to further reduce NOx that passes through the LNT. Engine exhaust PM is filtered and trapped by the DPF reducing the tailpipe PM emissions.

The paper covers the NOx performance evaluation of an LNT + SCR system designed to meet the 2010 on-highway heavy-duty (HD) US EPA emission standards. The system combines a fuel reformer catalyst (REF), lean NOx trap (LNT), diesel particulate filter (DPF), and selective catalytic reduction (SCR) in series, to reduce engine-out NOx and PM. System NOx reduction performance was verified in an engine dynamometer test cell, using a 2007 7.6L medium-duty engine. System NOx performance was characterized using fresh LNT and SCR along with hydrothermal aged LNT and fresh SCR. Test results show levels consistent with EPA 2010 limits under various test conditions. Catalysts performance was characterized at eight steady engine-operating conditions (A100, B50, B75, A75, B100, C100, C75, C50, across a 13-mode Supplemental Emission Test (SET), and an on-highway Heavy Duty Federal Test Procedure (HD-FTP).

Global environmental and economic concerns regarding increasing fuel consumption and greenhouse gas emission are driving changes to legislative regulations and consumer demand. As regulations become more stringent, advanced engine technologies must be developed and implemented to realize desired benefits. Discrete variable valve lift technology is a targeted means to achieve improved fuel economy in gasoline engines. By limiting intake air flow with an engine valve, as opposed to standard throttling, road-load pumping losses are reduced resulting in improved fuel economy. This paper focuses on the design and development of a switching roller finger follower system which enables two mode discrete variable valve lift on end pivot roller finger follower valvetrains. The system configuration presented includes a four-cylinder passenger car engine with an electro-hydraulic oil control valve, dual feed hydraulic lash adjuster, and switching roller finger follower.

ADVISOR is a flexible drivetrain analysis tool, developed in MATLAB/Simulink® to compare fuel economy and emissions performance between different drivetrain configurations. This paper reports a couple of numerical issues with application of ADVISOR 2002 to commercial vehicles with traditional powertrain systems. One instance is when ADVISOR model is set up to simulate running a heavy-duty (HD) truck with an automated manual transmission (AMT) on a demanding pickup-delivery duty cycle. The other is highlighted during an analysis of a medium-duty (MD) truck with an automatic transmission (AT) where wide-open throttle, i.e., fast acceleration is requested. These two cases have shown different numerical difficulties by using ADVISOR 2002. Based on studying the details of the models, solutions to these numerical issues are developed. The simulation results will demonstrate the effectiveness of these solutions.

An advanced exhaust aftertreatment system is being developed using a fuel dosing system, mixing elements, fuel reformer, lean NOx trap (LNT), diesel particulate filter (DPF) and a selective catalytic reduction (SCR) catalyst arranged in series for both on- and off- highway diesel engines to meet the upcoming emissions regulations. This system utilizes a fuel reformer to generate hydrogen (H2) and carbon monoxide (CO) from injected diesel fuel. These reductants are used to regenerate and desulfate the LNT catalyst. NOx emissions are reduced using the combination of the LNT and SCR catalysts. During LNT regeneration, ammonia is intentionally released from the LNT and stored on the downstream SCR catalyst to further reduce NOx that passed through the LNT catalyst. This paper addresses LNT and SCR catalyst degradation as these were subjected to 150 desulfation events using a pre-production 2007 medium heavy-duty, on-highway diesel engine.

Due to the increasing application of polymer material in structural components within automotive industry, the application of robust structural design becomes increasingly more important. In this paper, a fractured polymer component, a position sensor rotor from a heavy-duty diesel Exhaust Gas Recirculation (EGR) valve, was studied in detail by finite element methods (FEM). This process included three stages. First, a 3D nonlinear FEM (contact element) was constructed and sensor rotor stress and deformation were obtained under assembly and operation environments. The Coulomb-Mohr failure theory was employed to evaluate the existing design margin relative to the load cases understood from the application. In the second stage, a design sensitivity analysis was performed to select the robust design alternatives from among several improved designs.

Eaton has developed a prototype hydraulic hybrid vehicle energy management system that substantially improves fuel economy and reduces harmful emissions. The system was developed cooperatively with the U.S. Environmental Protection Agency (EPA), Navistar Inc., and the U.S. Army. The system has demonstrated fuel economy improvements in real world use of up to 50 percent while simultaneously reducing carbon emissions by up to 30 percent. The first real world application of the technology will be in parcel delivery vehicles owned by United Parcel Service (UPS). The hybrid vehicle energy management system components will be described and principles of operation explained. Major properties of the system will be examined and it will be shown why the hydraulic hybrid system is well suited for the parcel delivery vehicle application. Several secondary beneficial properties of the system will also be discussed.

This paper discusses the effect of torque vectoring differential on improving vehicle handling and stability performance. The torque vectoring concept has been analyzed. The vehicle discussed in this paper is an AWD vehicle with torque vectoring differential in the rear and a torque biasing center differential. First, simulation results with vehicle model in CarSim® and torque vectoring control algorithm in Matlab®/Simulink® is discussed. Then, experimental results for vehicle tested at winter and summer test facility is presented. Both simulation and experimental results demonstrate the effectiveness of torque vectoring differential on vehicle handling & stability.

Eaton has developed a prototype hydraulic hybrid vehicle energy management system that substantially improves fuel economy and reduces harmful emissions. The system was developed cooperatively with the U.S. Environmental Protection Agency (EPA), Navistar Inc., and the U.S. Army. The system has demonstrated fuel economy improvements in real world use of up to 50 percent while simultaneously reducing carbon emissions by up to 30 percent. The first real world application of the technology will be in parcel delivery vehicles owned by United Parcel Service (UPS). The hybrid vehicle energy management system components will be described and principles of operation explained. Major properties of the system will be examined and it will be shown why the hydraulic hybrid system is well suited for the parcel delivery vehicle application. Several secondary beneficial properties of the system will also be discussed.

On-board measurements of fuel consumption and vehicle exhaust emissions of NOx, HC, CO, CO2, and PM are being conducted for three types of commercially available city buses in Guangzhou, China. The selected vehicles for this test include a diesel bus with Eaton hybrid electric powertrain, a conventional diesel bus with automated mechanical transmission (AMT), and a LPG powered city bus with manual transmission (MT). All of the tested vehicles were instrumented with on-board measurements. Horiba OBS-2200 was used for measuring NOx, HC, and CO emissions; ELPI (Electrical Low Pressure Impactor) was used for PM measurement. The vehicles were tested at Hainan National Proving Ground in southern China. Test data of fuel consumption and exhaust emissions were analyzed. The city bus with Eaton hybrid electric powertrain demonstrated more than 27% fuel consumption reduction over the conventional diesel powered bus, and over 68% over the LPG bus.

This paper addresses Hardware-In-the-Loop modeling and simulation for Diesel aftertreatment controls system development. Lean NOx Trap (LNT) based aftertreatment system is an efficient way to reduce NOx emission from diesel engines. From control system perspective, the main challenge in aftertreatment system is to predict temperature at various locations and estimate the stored NOx in LNT. Accurate estimation of temperatures and NOx stored in the LNT will result in an efficient system control with less fuel penalty while still maintaining the emission requirements. The optimization of the controls will prolong the lifespan of the system by avoiding overheating the catalysts, and slow the progressive process of component aging. Under real world conditions, it is quite difficult and costly to test the performance of a such complex controller by using only vehicle tests and engine cells.

Recent studies have shown that hydraulic hybrid drivelines can significantly improve fuel savings for medium weight vehicles on stop-start drive cycles. In a series hydraulic hybrid (SHH) architecture, the conventional mechanical driveline is replaced with a hydraulic driveline that decouples vehicle speed from engine speed. In an effort to increase the design space, this paper explores the use of a fixed displacement checkball piston pump in an SHH driveline. This paper identifies the potential life-limiting components of a fixed displacement checkball piston pump and examines the likelihood of surface fatigue in the check valves themselves. Numerical analysis in ABAQUS software suggests that under worst case operating conditions, cyclic pressure loading will result in low-cycle plastic deformation of check valve surfaces.

A special vehicle dynamometer has been developed that allows engineers to evaluate driveline components and control algorithms for advanced, electrically-assisted drive systems on commercial vehicles. This dynamometer allows objective measurements of performance, fuel economy, and exhaust emissions, while the full vehicle is operated over a specified driving cycle. This system can be used to exercise the electric motor, engine, transmission and battery systems on Medium Duty Hybrid Trucks - in regeneration as well as power mode - all indoors and in a controlled, repeatable environment. This paper will provide descriptions of the operating goals, control features, and results of testing with this dynamometer. Once the various parameters have been optimized for fuel and emissions performance in this facility, the vehicle can be evaluated where it counts - on the road.

Diesel exhaust aftertreatment systems are required for meeting Final Tier 4 emission regulations. This paper addresses an aftertreatment system designed to meet the Final Tier 4 emission standards for nonroad vehicle markets. The aftertreatment system consists of a fuel dosing system, mixing elements, fuel vaporizer, fuel reformer, lean NOx trap (LNT), diesel particulate filter (DPF), and an optional selective catalytic reduction (SCR) catalyst. Aftertreatment system performance, both with and without the SCR, was characterized in an engine dynamometer test cell, using a 4.5 liter, pre-production diesel engine. The engine out NOx nominally ranged between 1.6 and 2.0 g/kW-hr while all operating modes ranged between 1.2 and 2.8 g/kW-hr. The engine out particulate matter was calibrated to approximately 0.1 g/kW-hr for various power ratings. Three engine power ratings of 104 kW, 85 kW and 78 kW were evaluated.

Increased demands for reduction of fuel consumption and CO2 emissions are driven by the global warming. To meet these challenges with respect to the passenger car segment the strategy of utilizing IC-engine downsizing has shown to be effective. In order to additionally meet requirements for high power and torque output supercharging is required. This can be realized using e.g. turbo-chargers, roots blowers or a combination of several such devices for the highest specific power segment. Both turbo-chargers and roots blowers can be strong sources of sound depending on the operating conditions and extensive NVH abatements such as resonators and encapsulation might be required to achieve superior vehicle NVH. For an efficient resonator tuning process in-duct acoustic source data is required. No published studies exists that describe how the gas exchange process for roots blowers can be described by acoustic sources in the frequency domain.