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Many lubrication environments in various equipment applications are inherently contaminated with debris and require mechanical components that are, as much as possible, resistant to the potential detrimental effects of debris particles. Many design engineers and lubricant specialists often overlook potential relationships between the various component failure modes, lubricant debris contamination levels, and engineering solutions that are created to overcome them. In addition, design engineers are in need of an analysis tool that can combine the various amounts of cumulative bearing damage occurring over time. As an example, bearing functional surfaces in many cases are progressively damaged over the life of the equipment. A new surface analysis tool is available which allows surface damage analysis to be completed at various stages of equipment life. This new surface analysis tool is appropriately called Debris Signature Analysis(sm).

The implementation of emission standards has brought significant reductions in vehicle emissions in the EU, but road transport is still a major source of air pollution. Future emission standards will aim at making road vehicles as clean as possible under a wide range of driving conditions and throughout their complete lifetime. The current paper presents the methodology followed by the Consortium for ultra LOw Vehicle Emissions (CLOVE) to support the preparation of the Euro 7 proposal. As a first step, the emission performance of the latest-technology vehicles under various driving conditions was evaluated. Towards this direction, an emissions database was developed, containing data from a wide range of tests, both within and beyond the current RDE boundaries.

With the adoption of the Worldwide harmonized Light Vehicles Test Procedure (WLTP) and the Real Driving Emissions (RDE) regulations for testing and monitoring the vehicle pollutant emissions, as well as CO2 and fuel consumption, the gap between real world and type approval performances is expected to decrease to a large extent. With respect to CO2, however, WLTP is not expected to fully eliminate the reported 40% discrepancy between real world and type approval values. This is mainly attributed to the fact that laboratory tests take place under average controlled conditions that do not fully replicate the environmental and traffic conditions experienced over daily driving across Europe. In addition, any uncertainties of a pre-defined test protocol and the vehicle operation can be optimized to lower the CO2 emissions of the type approval test. Such issues can be minimized in principle with the adoption of a real-world test for fuel consumption.

In a gasoline engine, the unswept in-cylinder residual gas and introduction of external EGR is one of the important means of controlling engine raw NOx emissions and improving part load fuel economy via reduction of pumping losses. Since the trapped in-cylinder Residual Gas Fraction (RGF, comprised of both internal, and external) significantly affects the combustion process, on-line diagnosis and monitoring of in-cylinder RGF is very important to the understanding of the in-cylinder dilution condition. This is critical during the combustion system development testing and calibration processes. However, on-line measurement of in-cylinder RGF is difficult and requires an expensive exhaust gas analyzer, making it impractical for every application. Other existing methods, based on measured intake and exhaust pressures (steady state or dynamic traces) to calculate gas mass flowrate across the cylinder ports, provide a fast and economical solution to this problem.

The Frequency Response Function (FRF) is a fundamental component to identifying the dynamic characteristics of a system. FRF's have a significant impact on modal analysis and root cause analysis of NVH issues. In most cases the FRF can be easily measured, but there are instances when the measurement is unobtainable due to spatial constraints. This paper outlines a simple experimental method for obtaining a high quality input-output FRF of a structure in areas where an impact hammer can not reach during impact testing. Traditionally, the FRF in such an area is obtained by using a load cell extender with a hammer impact excitation. A common problem with this device is a double hit, that yields unacceptable results.

Virtual testing has grown to be an efficient tool in vehicle passive safety design. Most simulations currently are deterministic. Since the responses observed in real-life and standardized tests are greatly affected by scatter, a stochastic approach should be adopted in order to improve the predictability of the numerical responses with respect to the experimental data. In addition, an objective judgement of the performance of numerical models with respect to experimental data is necessary in order to improve the reliability of virtual testing. In the European VITES & ADVANCE project the software tool Adviser was developed in order to fulfil these two requirements. With Adviser, stochastic simulations can be performed and the quality of the numerical responses with respect to the experimental can be objectively rated using pre-defined and user-defined objective correlation criteria. The software Adviser was used to develop a stochastic HybridIII 50th% Madymo numerical model.

Economical steels with improved fatigue life performance continue to be sought for more demanding applications such as in the automotive and aerospace industries. Researchers at The Timken Company, pursuing improved fatigue performance in tapered roller bearings, have found that life is limited by large inclusion stringers that still exist in today's highly publicized steels. Stringers, by definition, are clusters of individual oxide particles observable in wrought steel. An ultrasonic method has been used to quantify the frequency of these stringers in steel in bearing components. The total length of these stringers has been correlated with bearing fatigue life. The use of this ultrasonic tool has expedited the development of the newly introduced Parapretnium™ steel. This air-melted steel has a stringer content less than nearly all of the other worldwide bearing steels evaluated and, in fact, its stringer content is approaching those low levels found only in vacuum-remelted steels.

This paper reports on DaimlerChrysler's participation in the Ad Hoc Diesel Fuels Test Program. This program was initiated by the U.S. Department of Energy and included major U.S. auto makers, major U.S. oil companies, and the Department of Energy. The purpose of this program was to identify diesel fuels and fuel properties that could facilitate the successful use of compression ignition engines in passenger cars and light-duty trucks in the United States at Tier 2 and LEV II tailpipe emissions standards. This portion of the program focused on minimizing engine-out particulates and NOx by using selected fuels, (not a matrix of fuel properties,) in steady state dynamometer tests on a modern, direct injection, common rail diesel engine.

An electro-mechanical infinitely variable transmission (eVT), comprising a pair of planetary trains interconnected with two electric machines and clutches, has been proposed. The transmission leverages the advantages of an output power-split configuration for low-speed operation and a compound power-split configuration for high-speed operation. It is capable of being operated in a number of operating modes including an eVT only mode and a hybrid mode when equipped with on-board energy storage devices. The transmission provides a compact, highly efficient and potentially low cost driveline solution for both conventional vehicles and hybrid electric vehicles. A virtual transmission prototype was built in EASY51. A base vehicle model was also constructed in EASY5 environment with Ricardo Powertrain Library components.

Charge motion is known to accelerate and stabilize combustion through its influence on turbulence intensity and flame propagation. The present work investigates the effect of charge motion generated by intake runner blockages on combustion characteristics and emissions under part-load conditions in SI engines. Firing experiments have been conducted on a DaimlerChrysler (DC) 2.4L 4-valve I4 engine, with spark range extending around the Maximum Brake Torque (MBT) timing. Three blockages with 20% open area are compared to the fully open baseline case under two operating conditions: 2.41 bar brake mean effective pressure (bmep) at 1600 rpm, and 0.78 bar bmep at 1200 rpm. The blocked areas are shaped to create different levels of swirl, tumble, and cross-tumble. Crank-angle resolved pressures have been acquired, including cylinders 1 and 4, intake runners 1 and 4 upstream and downstream of the blockage, and exhaust runners 1 and 4.

The goal of this work was to investigate the possibilities of applying high EGR rates with low NOx and PM emission levels on a two-stage turbocharged 12 liter heavy duty diesel engine. The EGR is applied by using a long and short route EGR system. For the ESC operating points A25 and C100 EGR is applied, such that the NOx emission is 0.5 g/kWh. Lowest PM level and BSFC are achieved when long route EGR is applied in A25 and short route is applied in C100. Increasing the fuel line pressure is an effective way to reduce PM at high EGR rate engine running conditions. At a fuel line pressure of 2400 bar PM emission are 0.06 g/kWh for A25 and 0.54 g/kWh for C100. At C100 the PM reduction coincides with also a significant fuel consumption improvement. Retarding the injection timing at C100 can improve the PM emission further to a level of 0.13 g/kWh at the expense of an increase in BSFC.

Many lubrication environments in various equipment applications are inherently contaminated with debris and require mechanical components that are, as much as possible, resistant to the potential detrimental effects of debris particles. Many design engineers and lubricant specialists often overlook potential relationships between the various component failure modes, lubricant debris contamination level and the engineering solutions that are created to overcome them. Various methods for evaluating the effectiveness of debris resistant bearings have been proposed for development. Some of these methods have become standard methods within each bearing manufacturer's organization. Using an experimental method, performance evaluation results of tapered roller bearings in the areas of material fatigue will be discussed. The potential performance advantages will be placed in context of understanding the performance needs in the application.

This paper focusses on the application of bioalcohols (ethanol and butanol) derived from seaweed in Heavy-Duty (HD) Compression Ignition (CI) combustion engines. Seaweed-based fuels do not claim land and are not in competition with the food chain. Currently, the application of high octane bioalcohols is limited to Spark Ignition (SI) engines. The Reactivity Controlled Compression Ignition (RCCI) combustion concept allows the use of these low carbon fuels in CI engines which have higher efficiencies associated with them than SI engines. This contributes to the reduction of tailpipe CO2 emissions as required by (future) legislation and reducing fuel consumption, i.e. Total-Cost-of-Ownership (TCO). Furthermore, it opens the HD transport market for these low carbon bioalcohol fuels from a novel sustainable biomass source. In this paper, both the production of seaweed-based fuels and the application of these fuels in CI engines is discussed.

Cam-phasing is increasingly considered as a feasible Variable Valve Timing (VVT) technology for production engines. Additional independent control variables in a dual-independent VVT engine increase the complexity of the system, and achieving its full benefit depends critically on devising an optimum control strategy. A traditional approach relying on hardware experiments to generate set-point maps for all independent control variables leads to an exponential increase in the number of required tests and prohibitive cost. Instead, this work formulates the task of defining actuator set-points as an optimization problem. In our previous study, an optimization framework was developed and demonstrated with the objective of maximizing torque at full load. This study extends the technique and uses the optimization framework to minimize fuel consumption of a VVT engine at part load.

Reactivity Controlled Compression Ignition (RCCI) combines very high thermal efficiencies with ultra-low engine out NOx and PM emissions. Moreover, it enables the use of a wide range of fuels. As this pre-mixed combustion concept relies on controlled auto-ignition, closed-loop combustion control is essential to guarantee safe and stable operation under varying operating conditions. This work presents a coordinated air-fuel path controller for RCCI operation in a multi-cylinder heavy-duty engine. This is an essential step towards real-world application. Up to now, transient RCCI studies focused on individual cylinder control of the fuel path only. A systematic, model-based approach is followed to design a multivariable RCCI controller. Using the Frequency Response Function (FRF) method, linear models are identified for the air path and for the combustion process in the individual cylinders.

A promising SCR-only solution is presented to meet post-2010 NOx emission targets for heavy duty applications. The proposed concept is based on an engine from a EURO IV SCR application, which is considered optimal with respect to fuel economy and costs. The addition of advanced SCR after treatment comprising a standard and a close-coupled SCR catalyst offers a feasible emission solution, especially suited for EURO VI. In this paper, results of a simulation study are presented. This study concentrates on optimizing SCR deNOx performance. Simulation results of cold start FTP and WHTC test cycles are presented to demonstrate the potential of the close-coupled SCR concept. Comparison with measured engine out emissions of an EGR engine shows that a close-coupled SCR catalyst potentially has NOx reduction performance as good as EGR. Practical issues regarding the use of an SCR catalyst in close-coupled position will be addressed, as well as engine and exhaust layout.

This paper presents a cylinder pressure-based control (CPBC) system for conventional diesel combustion with high EGR levels. Besides the commonly applied heat release estimation, the CPBC system is extended with a new virtual NOx and PM sensor. Using available cylinder pressure information, these emissions are estimated using a physically based combustion model. This opens the route to advanced On-Board Diagnostics and to optimized fuel consumption and emissions during all operating conditions. The potential of closed-loop CA50 and IMEP control is demonstrated on a multi-cylinder heavy-duty EGR engine. For uncalibrated injectors and fuel variations, the combustion control system makes the engine performance robust for the applied variations and reduces the need for a time-consuming calibration process. Cylinder balancing is shown to enable auto-calibration of fuel injectors and to enhance fuel flexibility.

This paper reports on a study of the TNO venturi EGR system and the Johnson Matthey CRT particulates trap on a DAF 355 kW engine. The results obtained indicate that this EGR-CRT combination is an effective means to achieve EURO-4 emission level, while maintaining good fuel economy. EGR strategy, injection timing and air-fuel ratio were optimised in such a way that good regeneration conditions were obtained across most of the engine operating map. Also transient EGR control is optimised to combine low NOx emission during the ETC with good driveability and good engine out particulates emission. The size of the oxidation catalyst in the CRT was investigated. It appeared that the larger oxidation catalyst showed a better regeneration performance during a low temperature duty-cycle. Negative aspects of a larger oxidation catalyst are increased costs and increased NO2 emission (because of the catalyst ability to oxidise more NO into NO2).

Various methods for evaluating the effectiveness of debris resistant bearings have been proposed for development. Once evaluation methods are well established to select bearings, the user is faced with assessing severity and detrimental effects of a specific application's lubricant contamination on bearing performance. Many analysis tools have been suggested for determining this impact, including particle analysis for size distribution, type of material and contamination level. A novel approach for determining severity of damage has been investigated which attempts to integrate these typical tools with actual damage to functional surfaces. It seeks to provide a practical approach and is appropriately labeled Debris Signature Analysis. Results of actual assessments will be discussed and the assessment method described.

To meet future emission targets, it becomes increasingly important to optimize the synergy between engine and aftertreatment system. By using an integrated control approach minimal fluid (fuel and DEF) consumption is targeted within the constraints of emission legislation during real-world operation. In such concept, the on-line availability of engine-out NOx emission is crucial. Here, the use of a Virtual NOx sensor can be of great added-value. Virtual sensing enables more direct and robust emission control allowing, for example, engine-out NOx determination during conditions in which the hardware sensor is not available, such as cold start conditions. Furthermore, with use of the virtual sensor, the engine control strategy can be directly based on NOx emission data, resulting in reduced response time and improved transient emission control. This paper presents the development and on-line implementation of a Virtual NOx sensor, using in-cylinder pressure as main input.