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Technical Paper

“Virtual Engine/Powertrain/Vehicle” Simulation Tool Solves Complex Interacting System Issues

2003-03-03
2003-01-0372
An integrated simulation tool has been developed, which is applicable to a wide range of design issues. A key feature introduced for the first time by this new tool is that it is truly a single code, with identical handling of engine, powertrain, vehicle, hydraulics, electrical, thermal and control elements. Further, it contains multiple levels of engine models, so that the user can select the appropriate level for the time scale of the problem (e.g. real-time operation). One possible example of such a combined simulation is the present study of engine block vibration in the mounts. The simulation involved a fully coupled model of performance, thermodynamics and combustion, with the dynamics of the cranktrain, engine block and the driveline. It demonstrated the effect of combustion irregularity on engine shaking in the mounts.
Technical Paper

“Trapless” Trap – A Catalytic Combustion System of Diesel Particulates Using Ceramic Foam

1983-02-01
830082
“Trapless” Trap, which makes possible the effective collecting of particulates in diesel exhaust gas and their simultaneous combustion has been developed by use of a ceramic foam in combination with catalysts containing copper salt. From a TEM photograph, it was observed that the particulate was rapidly oxidized by mobile copper ion, showing worm-eaten like spots. Screening of various base metal salts by TGA presented CUCl2-KCl-NH4VO3 and CuCl2-KCl-(NH4)6Mo7O24 as very active catalysts for diesel particulate oxidation. They had thermal stability up to 900°C when they were supported on titania. The results obtained by measuring the back pressure using 1.8L diesel engine suggest the above trap to be a self-cleaning trapless trap.
Technical Paper

“Prediction of In-Cylinder Pressure, Temperature, and Loads Related to the Crank Slider Mechanism of I.C. Engines: A Computational Model”

2003-03-03
2003-01-0728
This paper describes the initial works related to the study of Internal Combustion Engines, as an object of mechanical design, at the Universidad Tecnológica de Pereira. It is reported a concise, complete methodology for simple model of internal combustion engine. The emphasis of the paper is placed on the use of the in-cylinder parameters (pressure and temperature) and inertial loads in the crank-slider mechanism to derive the loads that act on all the components of the crank-slider mechanism as well as the theoretical output torque for a given geometrical structure and inertial properties. These loads can then be used to estimate the preliminary dimensions of engine components in the initial stage of engine development. To obtain the pressure and temperature inside the cylinder, under different operation parameters, such as air fuel ratio and spark angle advance, a Zero dimensional model is applied. The heat transfer from the cylinder and friction are not taken into account.
Technical Paper

“Influence of Engine Variables on Exhaust Oxides of Nitrogen Concentrations from a Multi-Cylinder Engine”

1967-02-01
670482
The influence of engine variables on the concentration of oxides of nitrogen present in the exhaust of a multicylinder engine was studied. The concentrations of nitric oxide (NO) were measured with either a mass spectrometer or a non-dispersive infrared analyzer. The NO concentration was low for rich operation (deficient in oxygen) and increased with air-fuel ratio to a peak value at ratios slightly leaner than stoichiometric proportions. A further increase in air-fuel ratio resulted in reduced NO concentrations. Advanced spark timing, decreased manifold vacuum, increased coolant temperature and combustion chamber deposit buildup were also found to increase exhaust NO concentration. These results support either directly or indirectly the hypothesis that exhaust NO concentration is primarily a result of the peak combustion gas temperature and the available oxygen.
Technical Paper

“Future” Diesel Fuel Compositions - Their Influence on Particulates

1988-08-01
881173
Five different diesel fuels, having been made available by the mineral oil industry within the framework of a research program of the Coordinating European Council (CEC/PF-26), were examined in addition to this program by the Klöckner-Humboldt-Deutz AG by means of the 13-mode test in accordance with the former US legislation and the ECE regulation No. 49 and by US Transient Tests. The results have been compared with results based on commercial European diesel fuel. There has been observed the emission behaviour of an 8-cylinder NA engine with a “state of the art” direct fuel injection system by particularly taking into consideration the particulate emission and the particulate components. The gaseous emissions, particularly CO and HC, are unfavourably influenced by low cetane numbers being associated with increased aromaticity in the diesel fuel.
Technical Paper

“Catalytic Engine” NOx Reduction of Diesel Engines with New Concept Onboard Ammonia Synthesis System

1992-02-01
920469
Ammonia is one of the most useful compounds that react with NOx selectively on a catalyst, such as V2O5-TiO2, under oxygen containing exhaust gas. However ammonia cannot be stored because of its toxicity for the small power generator in populated areas or for the diesel vehicles. A new concept for NOx reduction in diesel engine using ammonia is introduced. This system is constructed from the hydrogen generator by fuel reformer, the ammonia synthesizer, SCR catalyst for NOx reduction and the gas injection system of reformed gas into the cylinder. Experimental results show that, the SCR catalyst provides a very high rate of NOx reduction, reformed gas injection into cylinder is very effective for particulate reduction. WHEN CONSIDERING INTERNAL COMBUSTION ENGINES of the 1990's the question of how to harmonize the engine with the natural environments is one of the greatest problems. The internal combustion engine changes a substance into energy via its explosive combustion.
Technical Paper

“Buckling” Failure Assessment for Long Cylinders

1976-02-01
760641
A new method for the structural study of long hydraulic cylinders has been developed. The rational analysis, taking cognizance of most known conditions and disturbances, is capable of an iterative type solution by computer. Some examples of its use are given, illustrating the effects of stroke length and mounting position on stresses, deflections, internal bearing loads, and critical axial load.
Technical Paper

‘Regulated’ and ‘Non-regulated’ Emissions from Modern European Passenger Cars

2006-04-03
2006-01-1516
Regulated emissions from four current production European vehicles were measured over the Common Artemis Driving Cycles (CADC). Particulate Mass and Particle Number measurements were made in accordance with the newly-developed draft Particulate Measurement Programme (PMP) developed for the UN-ECE's expert group on pollution and energy (GRPE). During the test programme measurements were also made of currently non-regulated emissions including PAHs and speciation of the particulate material and key hydrocarbons. CADC results are presented for each of the four vehicles tested (one conventional gasoline vehicle, two different types of diesel without Diesel Particulate Filter (DPF) and one diesel with DPF) with results measured on the regulated New European Driving Cycle (NEDC) test for comparison. The emissions results on the Artemis cycles showed some significant differences from those on the regulated (NEDC) test cycle.
Technical Paper

‘Issues and Behaviors of Airborne Particulate Matters under Microgravity Environment’

2004-07-19
2004-01-2328
During several ISS missions, there were false alarms at both US and Russian smoke detectors. High local airborne particulate concentrations and interior deposits are considered the causes for such anomalies. Alternatives are proposed to replace or complement these faulty smoke detectors. The entrained zeolite particles may play a role in causing problems with check valves and air save pumps in CDRA and Vozdukh. Another incidence has been the dispersion of particulates out of Metox regeneration oven. Particulate matters with aerodynamic diameter of 15 microns and above, which normally settle down on earth, stay airborne under micro-gravity and thereby cause the above-mentioned nuisances. The motion of such a particle along a gas stream with an initial velocity can be expressed by theoretical equations. Stokes' Law leads to the descriptions of inertial precipitation of aerosols that are important in solving the issues.
Technical Paper

λDSF: Dynamic Skip Fire with Homogeneous Lean Burn for Improved Fuel Consumption, Emissions and Drivability

2018-04-03
2018-01-0891
Dynamic skip fire (DSF) has shown significant fuel economy improvement potential via reduction of pumping losses that generally affect throttled spark-ignition (SI) engines. In DSF operation, individual cylinders are fired on-demand near peak efficiency to satisfy driver torque demand. For vehicles with a downsized-boosted 4-cylinder engine, DSF can reduce fuel consumption by 8% in the WLTC (Class 3) drive cycle. The relatively low cost of cylinder deactivation hardware further improves the production value of DSF. Lean burn strategies in gasoline engines have also demonstrated significant fuel efficiency gains resulting from reduced pumping losses and improved thermodynamic characteristics, such as higher specific heat ratio and lower heat losses. Fuel-air mixture stratification is generally required to achieve stable combustion at low loads.
Technical Paper

the identification and characterization of RUMBLE AND THUD

1960-01-01
600015
SIMULTANEOUS RECORDINGS of cylinder pressure, audible sound, and crankshaft motion have shown that rumble is a noise associated with bending vibrations of the crankshaft. The vibrations are caused by abnormally high rates of pressure rise near the top dead center piston position. In this study the high rates of pressure rise were obtained by inducting deposits into the the engine. Thud is a torsional vibration of the crankshaft, similar in sound to rumble but resulting from much earlier occurrence of the maximum rates of pressure rise. Rumble vibrations consisted of a fundamental frequency of 600 cps and higher harmonics in the 11/1 compression ratio V-8 laboratory engine used in the investigation. The audible noise of rumble was predominantly composed of the second harmonic or about 1200 cps.
Technical Paper

p>Thermomechanical Analysis of the Cylinder Head and Cylinder Block with the Liner of AFV Diesel Engine

2011-10-06
2011-28-0118
This paper deals with the Coupled thermo mechanical analysis of a cylinder head, cylinder block and crank case with the liner of an uprated engine. The existing engine develops 780 hp output with mechanical driven supercharger and the engine is uprated to 1000 hp by replacing the supercharger with a turbocharger and new Fuel injection equipment. For uprating any engine, the piston and cylinder head are the most vulnerable members due to increased mechanical and thermal loadings. Mechanical loading is due to the gas pressure in the gas chamber and its magnitude can be judged in terms of peak pressure. Thermal loading is due to temperature and the heat transfer conditions in the piston surface, cylinder liner and the cylinder head. The relative importance of the various loads applied on the head and cylinder block in operation are assessed and a method of predicting their influence on the structural integrity of the components described.
Technical Paper

mDSF: Improved Fuel Efficiency, Drivability and Vibrations via Dynamic Skip Fire and Miller Cycle Synergies

2019-04-02
2019-01-0227
mDSF is a novel cylinder deactivation technology developed at Tula Technology, which combines the torque control of Dynamic Skip Fire (DSF) with Miller cycle engines to optimize fuel efficiency at minimal cost. mDSF employs a valvetrain with variable valve lift plus deactivation and novel control algorithms founded on Tula’s proven DSF technology. This allows cylinders to dynamically alternate among 3 potential states: high-charge fire, low-charge fire, and skip (deactivation). The low-charge fire state is achieved through an aggressive Miller cycle with Early Intake Valve Closing (EIVC). The three operating states in mDSF can be used to simultaneously optimize engine efficiency and driveline vibrations. Acceleration performance is retained using the all-cylinder, high-charge firing mode.
Technical Paper

and Repeatability of Transient Heat Release Analysis for Heavy Duty Diesel Engines

2009-04-20
2009-01-1125
Reduced emissions, improved fuel economy, and improved performance are a priority for manufacturers of internal combustion engines. However, these three goals are normally interrelated and difficult to optimize simultaneously. Studying the experimental heat release provides a useful tool for combustion optimization. Heavy-duty diesel engines are inherently transient, even during steady state operation engine controls can vary due to exhaust gas recirculation (EGR) or aftertreatment requirements. This paper examines the heat release and the derived combustion characteristics during steady state and transient operation for a 1992 DDC series 60 engine and a 2004 Cummins ISM 370 engine. In-cylinder pressure was collected during repeat steady state SET and the heavy-duty transient FTP test cycles.
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