This article presents a detailed analysis of the potential of dimethyl ether (DME) fuel applications in SI engines. This paper presents the tests results completed on an 1.6-dm³ Opel Astra engine fueled by gaseous fuel as a mixture of LPG and DME. Dimethyl ether is a fuel with properties similar to liquid LPG fuel. In addition, DME is very well miscible with LPG, hence the possibility of creating a mixture with any DME divisions. The assessment of the possibility of using DME as a component of the mixture was carried out with the use of a chassis dynamometer and equipment, enabling an analysis of the changes taking place inside the cylinder. The results of the analyses are the parameters of the thermodynamic processes describing changes in the engine cylinder.

Vibration can have a significant impact on long-term health, driver comfort, and vehicle performance. With a focus on steering wheel vibrations, this study examines both general and local vibrations that affect the driver. Under real-world conditions, a series of controlled test drives were conducted, with high-precision accelerometers mounted on the driver’s seat and steering wheel recording vibration data. The measurements were conducted in accordance with ISO 5349 and ISO 2631-1, which guaranteed a consistent assessment of vibration exposure. The results suggest that the daily vibration exposure for general vibrations at the driver’s seat is significantly lower than the legal limit, as evidenced by the presence of significant frequencies in the vertical (Z) axis. Nevertheless, steering wheel vibrations may cause pain due to their proximity to the resonance frequencies of the human hand–arm system, which have frequency maxima at approximately 35 Hz and harmonic 70 Hz. Additionally, the vibration intensity was elevated at vehicle velocities between 70 and 80 km/h, suggesting the potential presence of a resonance effect within the suspension or powertrain. The results emphasize the significance of advanced vibration reduction strategies in enhancing driver comfort and safety, including the implementation of a well-designed steering system and enhanced seat absorption. This research offers valuable insights for automotive engineers and ergonomics specialists who are interested in minimizing long-term health risks and vibration-induced fatigue. The aim of this study is to indicate the areas of the drive system fault that have a direct impact on the vibrations of the body structure. The article presents an analysis of the recorded vibration results based on which of the areas of change in the comfort of using the vehicle were selected.

The paper presented the dynamics of a vehicle fueled by hybrid fuel, i.e., LPG–DME mixture. The basis for the assessment was the T-ω characteristics of the SI engine with a capacity of 1.6 dm³, determined by the authors for several selected loads and DME mass shares in the engine supply mixture. The analysis and comparison of the impact of the composition of the LPG–DME mixture on the dynamic properties were carried out for the passenger car OPEL Astra, powered by an engine for which T- ω characteristics were determined earlier on the test bench. It has been shown that the mass share of DME in the LPG–DME mixture does not significantly reduce the dynamic index of the car. In addition, the scope of changes in the mass fraction of DME in the mixture was also determined, which will ensure the vehicle performance similar to the power and torque parameters obtained for an engine powered solely by LPG. The received results have made it possible to determine changes in the value of the maximum dynamic coefficient, maximum acceleration, and car acceleration time for selected engine loads and various DME shares in the mixture. The thesis that DME can be considered as an activator of the combustion process and may have an impact on the vehicle dynamics is confirmed.

This article presents a proposal to describe the pressure changes in the combustion chamber of an engine as a function of the angle of rotation of the crankshaft, taking into account changes in rotational speed resulting from acceleration. The aim of the proposed model is to determine variable piston forces in simulation studies of torsional vibrations of a crankshaft with a vibration damper during the acceleration process. Its essence is the use of a Fourier series as a continuous function to describe pressure changes in one cycle of work. Such a solution is required due to the variable integration step during the simulation. It was proposed to determine the series coefficients on the basis of a Fourier transform of the averaged waveform of a discreet open indicator diagram, calculated for the registration of successive cycles. Recording of the indicative pressure waveforms and shaft angle sensor signals was carried out during tests on the chassis dynamometer. An analysis of the influence of the adopted number of series coefficients on the representation of signal energy was carried out. The model can also take into account the phenomenon of work cycle uniqueness by introducing random changes in the coefficients with magnitudes set on the basis of determined standard deviations for each coefficient of the series. An indispensable supplement to the model is a description of changes in the engine rotational speed, used as a control signal for the PID controller in the simulation of the load performed by the dynamometer. The accuracy of determining the instantaneous rotational speed was analyzed on the basis of signals from the crankshaft position angle sensor and the piston top dead center (TDC) sensor. Limitations resulting from the parameters of digital signal recording were defined.

The goal of this article is to present the design assumptions of an energy storage for a Formula Student electric car equipped with one electric motor. The correct selection of the parameters of the energy storage is dictated by the regulations applicable to all cars competing in this class, especially the maximum battery power. The growing interest in electric cars is visible also in motorsport, where are created new competitions and classes specifically for BEV (Battery Electric Vehicle). The study presents a description of the requirements contained in the competition regulations regarding the energy storage in the Formula Student vehicle, an overview of the cells that can be used in the battery and the selection of the most optimal among several solutions. Based on specific requirements, the arrangement of cells inside the battery was designed, divided into smaller segments and their connection, placed in a safe housing in the form of container.

This paper presents an analysis of the dynamic parameters of vehicles powered by an electric drive unit based on a permanent magnet synchronous motor (PMSM) and a conventional drive system based on a spark-ignition combustion engine. The research subjects were a Mercedes-Benz EQA 250+ and an Audi A3 8V 35 TFSI with a turbocharged 1.5 dm³ engine. The paper presents an analysis of changes in power and torque as a function of engine speed (ICE) and driving speed of the electric vehicle (BEV). The study demonstrated fundamental differences, primarily the progression of the external characteristic curves of the engines and changes in vehicle dynamics. The research shows differences in the elasticity depending on the type of the drive motor. The research was conducted using a chassis dynamometer that allowed for a deeper understanding of the operation of the electric vehicle drive system and the identification of significant differences and dependencies in the external characteristics.