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The development and calibration of modern combustion engines is challenging in the area of continuously tightening emission limits and the necessity for meeting real driving emissions regulations. A focus is on the knowledge of the internal engine processes and the determination of pollutants formations in order to predict the engine emissions. A physical model-based development provides an insight into hardly measurable phenomena properties and is robust against changing input data. With increasing modeling depth the required computing capacities increase. As an alternative to physical modeling, data-driven machine learning methods can be used to enable high-performance modeling accuracy. However, these are dependent on the learned data. To combine the performance and robustness of both types of modeling a hybrid application of data-driven and physical models is developed in this paper as a grey box model for the exhaust emission prediction of a commercial vehicle diesel engine.

This paper investigates an optimal design of a diesel engine and after-treatment systems for a series hybrid electric forklift application. A holistic modeling approach is developed in GT-Suite® to establish a model-based hardware definition for a diesel engine and an after-treatment system to accurately predict engine performance and emissions. The used engine model is validated with the experimental data. The engine design parameters including compression ratio, boost level, air-fuel ratio (AFR), injection timing, and injection pressure are optimized at a single operating point for the series hybrid electric vehicle, together with the performance of the after-treatment components. The engine and after-treatment models are then coupled with a series hybrid electric powertrain to evaluate the performance of the forklift in the standard VDI 2198 drive cycle.

This study aims to provide modeling and control approaches for automated manual passenger and commercial vehicle transmissions in order to improve the overall disengagement-gear shifting-engagement performance using electromagnetic powder clutch (EMPC). The rationale behind selecting this clutch is its rapid behavior. During the modeling procedure of the EMPC, the analogy between this type of clutches and dry plate friction clutches has been exploited and a simple control method is proposed. The study also includes modeling method for gear shifting and selecting mechanisms of the automated manual transmission gearbox as well as development and implementation of controllers which is designed for these mechanisms. Automated manual transmission gearbox is utilized due to its combination of ease of construction and ability for electronic automation.

An aerodynamic analysis methodology which makes efficient use of ANSA and FLUENT software's in the aerodynamic design of tractor-trailer class heavy commercial road vehicles is presented. The aerodynamic drag coefficient of the truck is used as the main control parameter to evaluate the performance of the methodology. Analysis methodology development activities include determining optimal FLUENT software analysis parameters for the defined problem (RANS based turbulence models, wall boundary layer models, solution schemes) and the necessary ANSA mesh generation parameters (boundary layer number and growth rate, wall surface mesh resolution, total mesh resolution). Proposed methodology is first constructed based on CFD simulations for the zero-degree yaw angle case of the 1/8 sized GCM geometry. The present results are within 1% of the experimental data.

“Hot Bulb engines” was the popular name of the early direct injected 2-stroke oil engine, invented and patented by Carl W. Weiss 1897. This paper covers engines of this design, built under license in Sweden by various manufacturers. The continuous development is demonstrated through examples of different combustion chamber designs. The material is based on official engine performance evaluations on stationary engines and farm tractors from 1899 to 1995 made by the National Machinery Testing Institute in Sweden (SMP). Hot-bulb, diesel and spark ignited engines are compared regarding efficiency, brake mean effective pressure and specific power (power per displaced volume). The evaluated hot-bulb engines had a fairly good efficiency, well matching the contemporary diesel engines. At low mean effective pressures, the efficiency of the hot-bulb engines was even better than that of subsequent diesel engines.