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The purpose of the study was to determine the effect of the fuel used in the spark-ignition engine of the selected vehicle on the characteristics of maximum torque and power at the crankshaft of the engine as a function of crankshaft speed and the content of components in the exhaust gas. The vehicle engine was tested on a stand equipped with V-tech VT-2/B2 chassis dynamometer, MAHA MET 6.3 exhaust gas analyzer and engine parameter monitoring system using OBD standard. The tests used two commercial fuels with different test octane number (RON) values of 95 and 100 octanes. Measurement of the characteristics of the maximum torque, power on the crankshaft and the total power losses in the drive system, the contact of the wheels with the rollers of the dynamometer and the dynamometer as a function of the crankshaft rotational speed was carried out using the acceleration method with a dynamic load comprising the braking torque of the rotating masses and the electro-swirl brake. On the basis of the test results, engine and drive system parameters of the vehicle using the software for generating driving test runs “the calculation of gearshift points for the WLTC cycle”, a set of measuring points determining the values of the engine crankshaft speed and the torque generated by the engine crankshaft was determined. The parameters of the selected engine operating conditions are within the ranges specified by the software for generating the selected test runs. The content of selected exhaust gas components (carbon monoxide CO, carbon dioxide CO2, other hydrocarbons HC, oxygen O2, λ coefficient, nitrogen oxides NO and nitrogen dioxide NO2) was measured for the selected operating parameters of the vehicle for the tested fuels. On the basis of the results of the toxicity measurements, analytical models determining the content of individual components in the exhaust gases as a function of the crankshaft rotational speed and the torque generated on the crankshaft and software simulating the exhaust emissions of the selected vehicle moving under dynamic conditions were developed.

The development of wind energy has been observed for many years. Both construction firms and the scientific world are analyzing new design solutions, atmospheric conditions and the technical performance achieved. The main goal of this research is to evaluate the requirements that have to be met to design wind power stations that would be an optimal fit for the climatic conditions in Poland. This study combines the results of empirical studies on wind velocity distributions with the physical fundamentals of wind power station design. This paper presents modelling of the relationships between wind velocity distributions observed in Poland and technical requirements for wind power stations design. The wind velocities distributions for various locations in Poland are determined and expressed in Weibull distribution parameters. Theoretical computations concerning the dependence of wind power stations as function of wind speed and air’s physical properties are presented. Conclusions important for the design of power stations fitted to the atmospheric conditions in Poland are given. LabVIEW 2021 was used for computer modeling.

For many years, technological progress has been observed in the field of minimizing energy consumption by devices and increasing the efficiency of energy generation from freely available sources. Energy harvesting (EH) is one of the ways to increase the energy available in vehicles. The manuscript presents the results of a series of laboratory tests carried out in a wind tunnel using a 1:10 scale model of an SUV. The aim of the tests was to measure the air velocity in the footsteps of the car. The speed field has been identified at more than 188,000 points in the space behind or next to the car, considering the symmetry of the vehicle. The total energy was aggregated for 2760 points in a vertical plane perpendicular to the plane of symmetry. From the tests carried out, it was found that the highest speed was achieved just behind the trunk of the car, at a distance of about 20% of the length of the car. Interestingly, the speed in this area was higher than the speed of the car.

The Vortex Ring State (VRS) of the main rotor is one of the threats for the safety of a helicopter. Therefore this phenomenon has been intensively investigated for several years, in order to understand the mechanisms of its development and the possibilities of avoiding the danger flight regime. The paper presents a research methodology applied for investigations of development of the VRS of the main rotor of a helicopter. The object of investigation was a model of a helicopter with a powered rotor, placed in a low-speed wind tunnel with test section diameter of 1.5 m. The investigation includes a strain gage measurements and flow visualization with the Particle Image Velocimetry (PIV) method. The results show the decrease in the thrust generated by the main rotor due to the VRS. The velocity field, measured with PIV method, shows the process of the VRS forming, development and demise. The results proved the feasibility of the presented methodology for investigation of the Vortex Ring State.