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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.

Fuel economy can be part of a business case for a fleet making the decision to buy new HD hybrid drivetrain technologies. Chassis dynamometer tests using SAE Recommended Practice J2711 on a bus equipped with an Allison EP SYSTEM ™ hybrid system and operated on standard bus driving cycles have produced impressive gains of over 60%. Preliminary urban bus field tests, on the other hand, have shown lower fuel economy gains. The difference can be attributed, in part, to the use of accessories - most importantly air conditioning - which are parasitic loads on the vehicle. In this paper the characteristics of driving cycles are studied to determine those factors which have the strongest influence on fuel economy for hybrids. The data show that the number of stopping events in a route or cycle is a strong influence as is the average vehicle speed. Energy analysis will show the relationship of fuel economy benefit and battery energy within a driving cycle.

In the modern and fast growing automotive sector, reliability & durability are two terms of utmost importance along with weight & cost optimization. Therefore it is important to explore new technology which has less weight, low manufacturing cost and better strength. The new technology developed always seek for a quick, cost effective and reliable methodology for its design validation so that any modification can be made by identifying the failures. This paper presents the rig level test methodology to validate and to correlate the CAE derived strain levels, life cycle & failure mode of newly developed light weight stabilizer link for EV Bus suspension

IT does not yet seem to be recognized fully that it is the local temperature at the surface of contact and not the local specific pressure that chiefly determines the occurrence of seizure under extreme-pressure-lubrication conditions. This local temperature is the result of the temperature level of the parts lubricated, considered as a whole (“bulk” temperature) and of a superimposed instantaneous temperature rise (temperature “flash”) which is localized in the surface of contact. It appears typical for extreme-pressure-lubrication conditions, as met in gear practice, that the temperature flash is much higher than the bulk temperature. With existing conventional test methods for the determination of the protection against seizure afforded by EP lubricants, a considerable rise of the bulk temperature mostly occurs; as it cannot be controlled sufficiently; thus, leaving an unknown margin for the temperature flash, it renders impossible a reliable determination.

Estimation of soot deposited on a wall flow type DPF, is a vital information to ensure safe and efficient DPF management. Accuracy in determining mass of soot present inside the DPF ensures a correct regeneration management strategy in-terms of fuel efficiency and DPF safety considering soot overloading and too frequent regenerations. It also ensures an efficient detection of anomalies in the PM filtration mandated by the BSVI/EURO VI legislation as a part of On-board diagnostics. Classical approach of determining soot present inside DPF involves monitoring increase in pressure drop. Real time usage of such a model is limited by the inaccuracy of measuring pressure drop at low exhaust flows. Hence, contemporary engine controllers use pressure drop based models as a failsafe and estimate DPF soot loading by modelling soot release rate due to engine combustion and the rate at which it is oxidized.

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.

A large number of testing procedures have been developed to ensure vehicle safety in common and extreme driving situations. However, these conventional testing procedures are insufficient for testing autonomous vehicles. They have to handle unexpected scenarios with the same or less risk a human driver would take. Currently, safety related systems are not adequately tested, e.g. in collision avoidance scenarios with pedestrians. Examples are the change of pedestrian behaviour caused by interaction, environmental influences and personal aspects, which cannot be tested in real environments. It is proposed to use augmented reality techniques. This method can be seen as a new (Augmented) Pedestrian in the Loop testing procedure.

Combustion concepts for future SI engines try to meet CO2-emission commitments and legislation all over the world. Where the Diesel engine has an advantage by principle, the efficiency of the SI engine has to be improved significantly, while of course the exhaust emissions must not become worse. An approach is to reduce the gas exchange losses using fully variable valve trains on the intake side of the combustion engine. OptiVent is a patented new way of controlling the mass air flow in the cylinder of a combustion engine using opening valves during the compression phase of a four stroke engine. This technology regards a wider range of variability on the valvetrain components of the engine especially for opening the valves more than one time during a cycle. On the other hand it is necessary to combine this technology with direct injection to avoid fuel losses in the exhaust system and raising the exhaust hydrocarbon emission of the engine.

Vehicle electrification is a rapidly growing and developing technology. As with any new technology there are hurdles that must be overcome as development marches forward. Overcoming these obstacles will require new and innovative solutions. One area of electrification that is quickly developing is the ability to convert voltage from AC to DC and from DC to AC. This is important since the battery pack outputs a DC voltage which must be converted to AC to drive the electric motor. The reverse is true when braking, the AC voltage generated by the electric motor is converted to DC in order to charge the battery. The conversion of voltage back and forth is controlled through the use of an inverter. The inverter uses Insulated-Gate Bipolar Transistors or IGBTs which generate heat while in operation. As the IGBTs heat up their efficiency goes down. In order to maintain a high level of efficiency the circuity can be directly cooled through the use of a heat sink.

The findings presented in this paper are part of a long term project aimed at raising the science of heat transfer in internal combustion engine cooling galleries. Initial work has been undertaken by the authors and an experimental facility is able to simulate different sizes of coolant passages. External heat is applied and data for the forced convective, nucleate boiling and transition or critical heat flux (CHF) regimes has been obtained. The results highlighted in this paper attempt to quantify the effects of cooling passage surface roughness on the nucleate boiling regime. Tests have been conducted using aluminium test pieces with surface finishes described as smooth, intermediate and as-cast. It has been found that the as-cast surface increases the heat flux density in the nucleate boiling region over that of the smooth and intermediate surfaces.

Due to ever soaring fuel costs and even more stringent emission regulations which require more elaborate technical efforts and unfortunately lead to a negative trend on fuel economy as well, todays and future trucking business is extremely challenged. These facts create an urgent requirement for the engine manufacturer to offer an engine with an optimized cost-benefit-ratio for the trucking business. Mercedes-Benz, as the leader in the European commercial vehicle market - of which e. g. high fuel costs, long maintenance intervals and high engine power-to-weight ratios have always been key characteristics - has developed a new class 8 engine for the US market. The MBE 4000 is a 6 cylinder inline engine in the compact size and low weight category, but due to its displacement of 12,8 liters it offers high performance characteristics like heavier big block engines.

The results of several anti-knock studies are discussed in this paper. Road anti-knock performance for 1000 fuel blends covering the years 1940 to 1957 have been investigated. The laboratory Research octane numbers of these fuels covered the range from 80 to 105. The fuels were evaluated in 46 cars representing a cross-section of the automotive products for these years. The objective of these investigations was to determine the practical application of the laboratory to road octane rating relationships, and the effect of vehicles, and operating conditions on these relationships. The results show that there is a valid correlation between laboratory and road octane ratings. The relative importance of Research and Motor octane ratings on road performance is influenced by make of car, engine speed, throttle position, and distributor advance characteristics. It also indicated that aromatics improve, whereas olefins reduce high speed Modified Borderline ratings.

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.

To prevent engine scuffing in the field a new laboratory test called the Hot Tube Test has been established in order to evaluate the high temperature stability of diesel engine oils. In a strip mining application field test using 47 bulldozers powered by the same engine type, half of the engines suffered from piston scuffing failures when operated on a variety of commercially available API CD quality SAE 30 Grade engine oils. All the field test oils have been investigated using the Hot Tube Test, and an analysis of the results indicates that it would be possible to accurately predict scuffing failures by this test method. Furthermore, the reliability of this analysis has been verified by bench engine testing on reference oils. The reasons why the Hot Tube Test predicts the anti-scuffing performance of engine oils are discussed.

Over the last ten years there has been a steady growth in the market share of light-duty diesel engines, especially in Europe. At the same time, a general trend in petrol engine development has been seen, in which normal aspirated engines are being replaced by downsized turbocharged engines. Therefore, NVH engineers have to deal with new challenges. Turbochargers produce an aerodynamic noise in the frequency range above 1000Hz, which might influence the exterior and interior noise level. As a result, the additional requirement for acoustical components to reduce this flow noise is going to pose an increasing challenge for air intake system suppliers. This paper describes a new design of well-known wide band silencer first mentioned by A. Selamet, N.S.Dickey and J.M.Novak [1,2]. The silencer works according to the interference principle. The sound is guided into two or more parallel pipes of different lengths.