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Several mechanisms are discussed to understand the formation of both regulated and unregulated emissions in a high speed, direct injection, single cylinder diesel engine using low sulphur diesel fuel. Experiments were conducted over a wide range of injection pressures, EGR rates, injection timings and swirl ratios.

The increased demand in fuel economy and the reduction of CO₂ emissions results in continued efforts to downsize engines. The downsizing efforts result in engines with lower displacement as well as lower number of cylinders. ...The downsizing efforts result in engines with lower displacement as well as lower number of cylinders. In addition to cylinder and displacement downsizing the development community embarks on continued efforts toward down-speeding. ...The combination of the aforementioned factors results in engines which can have high levels of torsional vibrations. Such behavior can have detrimental effects on the drivetrain particularly during the development phase of these.

Past experimental studies conducted by the current authors on a 13 liter 16.7:1 compression ratio heavy-duty diesel engine have shown that diesel-Compressed Natural Gas (CNG) Reactivity Controlled Compression Ignition (RCCI) combustion targeting low NOx emissions becomes progressively difficult to control as the engine load is increased. ...Past experimental studies conducted by the current authors on a 13 liter 16.7:1 compression ratio heavy-duty diesel engine have shown that diesel-Compressed Natural Gas (CNG) Reactivity Controlled Compression Ignition (RCCI) combustion targeting low NOx emissions becomes progressively difficult to control as the engine load is increased. This is mainly due to difficulty in controlling reactivity levels at higher loads. ...This poor prediction was found at multiple engine speed and load points. To resolve this, multiple reaction mechanisms were evaluated and a new reaction mechanism, that combines the GRI Mech 3.0 mechanism with the Chalmers mechanism, was proposed.

Measures for reducing engine friction within the powertrain are assessed in this paper. The included measures work in combination with several new technologies such as new combustion technologies, downsizing and alternative fuels.

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. ...The lack of masking effects of the engine during the engine stop phases can cause other “unwanted” noise to become noticeable or more prominent. ...Other comfort related criteria like a stable 12V board supply during the engine start phase or A/C usage during the engine stop phase need to be considered as well. This paper provides an overview of start/stop systems and starter concepts.

The main purpose of this paper is to provide the fuels and engine development community more insight on the fuel type effects on engine out emissions and performance. ...Increased demand for highly fuel efficient propulsion systems drives the engine development community to develop advanced technologies allowing improving the overall thermal efficiency while maintaining low emission levels. ...In addition to improving the thermal efficiencies of the internal combustion engine itself the developments of fuels that allow improved combustion as well as lower the emissions footprint has intensified recently.

The seven part load points were specified by engine speed (RPM) and brake mean effective pressure (BMEP). Engine parameters such as pilot and main injection timing, pilot quantity, rail pressure, boost pressure and exhaust gas re-circulation (EGR) rate were kept the same and were not optimized for each fuel. ...The main purpose of this paper is to provide the fuels and engine development community more insight into the influence of fuel properties on engine out emissions and performance with low temperature PCI combustion. ...Effects of six different fuels on low temperature premixed compression ignition (PCI) combustion were experimentally investigated in this paper with a light-duty HSDI engine. The PCI combustion concept reduces NOx and smoke emissions simultaneously by low temperature and premixed combustion, respectively.

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 major component discussion will involve idle governing, aftertreatment modeling, engine model extension, and how a complete desktop test cell environment was realized. Finally, the reader will be shown how a virtual testing environment can be applied by harnessing known tools, and how this approach can play a crucial role in supporting the development and calibration community in their daily activity.

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 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 system architecture evaluation proved to be one of the key development items that determined the packaging in the projected vehicle platform.

Advantages regarding packaging can be realized with the use of two generators in combination with the V2 engine. Compared to other engine applications there is one decisive attribute of a range extender - the NVH behavior. ...The V2 engine concept presented in this paper is particularly suited to a low cost, modular vehicle concept. ...The operation of a range extender must be completely unnoticeable in order to realize the desired “electric driving” experience, particularly during engine start and stop. This requirement might seem easily achievable, but represents one of the biggest challenges for a combustion engine.

However, the necessity to also meet the limits of today's and future emission regulations makes it more and more difficult to maintain a high engine efficiency without the use of an expensive external exhaust gas after-treatment system. Therefore, new technologies that simultaneously prevent emission formation and reduce fuel consumption inside the internal combustion engine during the combustion process itself are of highest interest. ...Therefore, new technologies that simultaneously prevent emission formation and reduce fuel consumption inside the internal combustion engine during the combustion process itself are of highest interest. This paper analyzes the influence of a catalytic coating of the combustion chamber on combustion, emission formation and fuel consumption. ...For this purpose, test runs with a production 2.0-liter, 4-cylinder, 4-valve, double overhead camshaft (DOHC), port fuel injection (PFI) gasoline engine were performed. The various possible benefits of the catalytic coating mentioned above were separated by different engine setup combinations.

Stochastic Preignition (SPI) is an abnormal combustion event that occurs in a turbocharged engine and can lead to the loss in fuel economy and engine hardware damage, and in turn result in customer dissatisfaction. ...It is a significant limiting factor on the use and continued downsizing of turbocharged spark ignited direct injection (SIDI) gasoline engines. Understanding and mitigating all the factors that cause and influence the rate and severity of SPI occurrence are of critical importance to the engine’s continued use and fuel economy improvements for future designs. ...Understanding and mitigating all the factors that cause and influence the rate and severity of SPI occurrence are of critical importance to the engine’s continued use and fuel economy improvements for future designs. Previous studies have shown that the heavy molecular weight components of the fuel formulations are one factor that influences the rate of SPI from a turbocharged SIDI gasoline engine.

Increased customer expectation for NVH refinement creates a significant challenge for the integration of Diesel powertrains into passenger vehicles that might have been initially developed for gasoline engine applications. A significant factor in the refinement of Diesel powertrain sound quality is calibration optimization for NVH, which is often constrained by performance, emissions and fuel economy requirements.

There was no measurable impact of Biodiesel operation on the engine mechanics including fuel injection system.

The engine was developed utilizing a state-of-the-art newly developed charge motion design (CMD) process in combination with single cylinder investigations. The engine control unit has a modular basis and is realized using rapid prototyping hardware. ...Based on the TurboDISI engine presented earlier [1], [2], a new Spray Guided Turbo (SGT) concept with enhanced engine performance was developed. ...The turbocharged engine was modified towards utilizing a spray-guided combustion system with a central piezo injector location.

The simulations demonstrated the ability of the planetary gear coupled system to match the engine performance of the baseline 7.7 L 6 cylinder engine while providing an additional fuel consumption benefit when compared to independent integration of these technologies. ...Technologies that provide potential for significant improvements in engine efficiency include, engine downsizing/downspeeding (enabled by advanced boosting systems such as an electrically driven compressor), waste heat recovery through turbocompounding or organic Rankine cycle and 48 V mild hybridization. ...The 1D simulation tool GT-Power was used to evaluate the performance of this planetary gear enabled approach against an approach that integrates each of these technologies (a turbocompound turbine, a 48 V belt starter generator and a 48 V e-compressor) independently on a downsized four cylinder diesel engine applied in a medium heavy-duty class 6/7 vocational vehicle. The fuel consumption of both approaches was compared over the engine map and over engine certification test cycles.

Application strategies for CAI are developed on a single cylinder research engine with a fully variable valve train and direct injection. It is found that control of the CAI operating range can be achieved by realizing stratification of the in-cylinder charge. ...Based on the thermodynamic requirements, the necessary variability of the valve train for realization of CAI operation in multi-cylinder engines can be identified. A multi-cylinder engine with a mechanically variable valve train to realize the CAI combustion process is presented. ...Controlled Auto Ignition combustion systems have a high potential for fuel consumption and emissions reduction for gasoline engines in part load operation. Controlled auto ignition is initiated by reaching thermal ignition conditions at the end of compression.

In this paper this development methodology is described with the main focus on the optical diagnostics applied to assess the mixture formation process for an exemplary turbocharged DI SI engine. Optical diagnostics are performed on a flexible motored engine FloTec (Flexible Laser Optical Test Engine Concept), which is capable to be operated with metal flowboxes instead of prototype cylinder heads. ...Advanced technologies such as direct injection DI, turbocharging and variable valve timing, have lead to a significant evolution of the gasoline engine with positive effects on driving pleasure, fuel consumption and emissions. Today's developments are primarily focused on the implementation of improved full load characteristics for driving performance and fuel consumption reduction with stoichiometric operation, following the downsizing approach in combination with turbocharging and high specific power. ...The requirements of a relatively small cylinder displacement with high specific power and a wide flexibility of DI injection specifications lead to competing development targets and additionally to a high number of degrees of freedom during optimization.

Downsized direct-injected boosted gasoline engines with high specific power and torque output are leading the way to reduce fuel consumption in passenger car vehicles while maintaining the same performance when compared to applications with larger naturally aspirated engines. These downsized engines reach brake mean effective pressure levels which are in excess of 20 bar. ...These pre-ignition events are typically accompanied by very high cylinder peak pressures which can lead to severe damage if the engine is not designed to withstand these high cylinder pressures. ...This paper describes a systematic engine dyno testing approach to force the engine into pre-ignition in order to study and characterize these events.