Marcin Noga

This paper presents the results of research on the development of an exhaust gas aftertreatment system for a turbocharged five-stroke engine. This engine was designed and constructed at Cracow University of Technology. A characteristic feature of the five-stroke engine is the use of an additional expansion process to increase overall efficiency. A challenge for a catalytic converter is the fact that it has a low exhaust gas temperature. Two three-way catalytic converters were tested – one with a ceramic support and the second with a metal support. The results of the tests showed that the reactor with a ceramic support obtains an acceptable conversion efficiency starting with an exhaust gas temperature of 280°C. For the metal-support reactor, a few percent increase in torque and a  decrease in the brake-specific fuel consumption of the engine was obtained; however, the converter itself did not show signs of operation even with an exhaust gas temperature of over 380°C. The performed analyses highlighted directions of further development works in this area.

This article presents the results of experimental tests and simulations of a light-duty electric vehicle, in which the original lead-acid battery pack was replaced with a lightweight pack of nickel-metal-hydride (NiMH) batteries, which enabled a significant increase to the vehicle’s load capacity. The research was mainly focused on the aspect of electricity consumption and prediction of the range of the vehicle equipped with a new battery pack. The operation of a vehicle with total weights of 500 kg and 740 kg was analysed. Recorded vehicle speed waveforms were used to simulate vehicle motion in the Matlab/Advisor environment. The experiments showed a reduction in the specific energy consumption of a vehicle of lower weight, while simulation tests showed good compliance of the results of electricity consumption with experiments in relation to both the considered total vehicle weights.

Five biodynamic models are investigated to approximate vertical seat vibration transmissibility and mechanical impedance in an effort to reduce experimental time and data collection when designing vehicle seats. The research has found that these biodynamic models of two, three and four degrees of freedom are ideally suited for initial seat design, since whole body vibrations can be easily depicted at approximately 5Hz. Further research is necessary to investigate the resonant frequencies for defined anatomical structures, passenger variability and the use of a backrest support.