The article presents a numerical analysis of the intake system of a turbine jet engine in terms of parameter stability along its duct, following the occurrence of an intake vortex. This type of intake system is characterized by high susceptibility to intake vortex. In extreme cases, this type of phenomenon leads to the engine surge and even to the operation disruption (engine stalling). The article presents a developed model of the front part of the aircraft with an intake duct. The discretization process involved in the issue under consideration has been described. The airflow parameters corresponding to the conditions in such cases have been adopted and numerical calculations have been performed. The result is an intake vortex. Subsequently, significant cross sections in the intake system have been separated, on which the impact pressure distributions have been determined. The main part of the article is devoted to the analysis of pressure distributions. They have been subjected to quantitative analysis using the proposed pressure coefficient. The coefficient has provided quantitative information about the difference in pressure distributions for selected sections. The results obtained have provided information about mounting airflow instability in the flow duct caused by the intake vortex.

This paper presents the results of a numerical investigation into the effect of blade trailing-edge thickness and shape on the performance of a rotor ring model of axial fan. The numerical simulations carried out under this investigation provided the performance characteristics of efficiency, working medium power, and total pressure increase in the function of the volumetric flow rate of the rotor ring. The investigated blade trailing-edge thickness values were 1 mm, 2 mm, and 3 mm. The models for the simulation series were developed with rounded and sharp blade trailing edges, for all thickness values thereof. The rounded trailing blade edges were modelled in the form of an arc over which the conditions of tangency with the upper and lower contours of the airfoil were imposed. The blades of the modelled blade fan were designed with the NACA 65-810 airfoil. To verify the applied turbulence model and mesh settings, experimental tests of the model rotor ring were performed on an axial fan test bed. The obtained experimental data was compared with numerical results. The results showed a significant impact of the thickness and shape of the blade trailing edge on the performance characteristics of axial fans.

The paper presents the process of designing an unmanned Micro class aircraft, from the analysis of the dynamically developing market and the condition of the Polish Armed Forces to construction of objects and flight test. The possibilities and limitations of using miniature UAVs on the modern battlefield were determined. For the designed UAV the propulsion was selected based on tests carried out on the engine test bench. The avionics equipment was selected based on components readily available on the market. The object was then made and inspected in flight. During the flight tests, the aircraft performance was verified and compared with the assumptions. It has been shown that the developed object is able to fulfill the reconnaissance tasks entrusted to it, while maintaining the assumed simplicity of construction and low cost of execution and service.

The article presents the methodology of determining the basic aerodynamic characteristics using the Fluent theoretical method and the theoretical and experimental method using the Prodas program. Presented calculations were made for a 122 mm non-guided missile. In order to compare both methods, the results of calculations of coefficient of drag force, lift force coefficient and pitching moment coefficient as a function of incidence angle of attack and Mach number are shown in graphs.