Wind tunnel research on the influence of active airflow on the lift force generated by the airfoil

The paper discusses the results of wind tunnel tests of airfoils with additional active airflow applied to their upper surfaces. These studies were carried out for a range of velocities up to 28 m/s in an open wind tunnel. Several types of airfoils selected for the examination feature different geometries and are widely applied in today’s avia¬tion industry. The changes in the lift and drag force generated by these airfoils were recorded during the study. The test bench for the tests was equipped with a compressor and a vacuum pump to enable airflow through some holes on the airfoil upper surface. A rapid prototyping method and a 3D printer based on a powder printing technique were applied to print the airfoils. All of their surfaces were subject to surface grind¬ing to smooth their external surfaces. The wind tunnel tests with and without active airflow applied to airfoils are summarised in the paper

Aerodynamic Research of the Overpressure Device for Individual Transport

Paper proposes a solution of overpressure device for individual transport, the purpose of which is to accumulate the overpressure in a certain geometric area, through the use of specially designed three-dimensional structures. In order to verify the underlying assumptions of the idea, it was decided to perform a simulation study of air flow stream within the proposed unit. These studies were done in Star CD – Pro Star 3.2 software. Further studies were carried out on the actual real model. The verification was performed to compare and identify the main parameters of air flow through the three-dimensional structure

Analiza eksploatacyjnych obciążeń gazowych łożysk foliowych zespołu wytwornicowego silnika turbinowego podczas manewru przyspieszenia i hamowania

The paper examines loads acting on the drive unit of an unmanned helicopter during maneuvers of acceleration and braking. Particular attention is paid to loads of gas generator bearings nodes of a turbine engine which is applied in the helicopter designed. The study is based on the time courses of changes in velocity of the manned PZL W3-Falcon. The correlation of flight velocity change and time was approximated by the least squares method to determine changes in acceleration. This enabled to determine the values of the forces acting on gas generator bearings under static and dynamic conditions. These values were compared with the values obtained for jump-up and jump-down maneuvers. The investigation enabled to determine the extreme components loading of the drive unit, including gas generator bearings nodes.W artykule rozpatrzono stany obciążeń działające na zespół napędowy śmigłowca bezzałogowego podczas manewru przyspieszenia i hamowania. Szczególną uwagę poświęcono obciążeniom węzłów łożyskowych zespołu wytwornicowego silnika turbinowego, w który zostanie wyposażony projektowany śmigłowiec. Analizę dokonano na podstawie przebiegów czasowych zmian prędkości lotu załogowego śmigłowca PZL W3-Sokół. Zależność zmiany prędkości lotu w czasie aproksymowano metodą najmniejszych kwadratów, a następnie wyznaczono dla niej zmiany przyspieszeń. Na tej podstawie wyznaczono wartości sił działających na łożyska zespołu wytwornicowego w warunkach statycznych i dynamicznych. Wartości te porównano z wartościami uzyskanymi podczas manewru skok w górę i skok w dół. Przeprowadzone analizy służą do określenia ekstremalnych stanów obciążeń podzespołów zespołu napędowego, a w tym węzłów łożyskowych zespołu wytwornicowego

Diesel engine applicability in a light helicopter

W artykule zaprezentowano koncepcję zastosowania silnika Diesla jako jednostki napędowej lekkiego śmigłowca. Przedstawiono zalety i wady takiego rozwiązania w porównaniu z obecnie stosowanymi silnikami turbowałowymi. Proponowany silnik jest proekologiczną jednostką napędową ze względu na znacznie mniejszą emisję toksycznych składników spalin w porównaniu do silników turbowałowych. Jednocześnie poruszono problemy, które muszą być uwzględnione w aspekcie zamontowania silnika Diesla w śmigłowcu. Przedstawiono również główne parametry silnika, którymi powinien się on charakteryzować, aby zapewnić wymaganą moc i osiągi niezbędne do napędu lekkiego śmigłowca.The paper presents the concept of a diesel engine application as a power unit in a lightweight helicopter. The authors present the advantages and disadvantages of this design compared to existing turbine engines. The proposed engine is eco-friendly power unit due to the much less toxic exhaust emissions compared to turbo shaft engines. The paper also presents the problems that must be considered in the context of a diesel engine mounted in the helicopter. In the end the paper the main engine parameters, which should be characterized to ensure the required power and performance necessary to drive a light helicopter are presented

Mass optimizing of the brake disctolighttricycle

The article presents an optimization process of the brake disc in terms of mass and strength resistance. A model of the disc was made using three-dimensional software – Catia V5 (CAD). Model has been subjected to the parameterization process for the strength calculations. A brake disc was fixed at the location of the mounting screws and subjected to torque resulting from the braking process. As a result of calculations, a set of parameters that meet the established boundary conditions was obtained as shown in the article

Numerical analysis of the horizont stabilizer influence on the Gyroplane Aerodynamic characteristics

W pracy przedstawiono wyniki symulacji opływu modelu wiatrakowca bez wpływu wirnika nośnego oraz śmigieł pchających. Trójwymiarowe obliczenia wykonano za pomocą programu ANSYS Fluent. Na podstawie przeprowadzonych obliczeń wyznaczono podstawowe charakterystyki aerodynamiczne. Dodatkowo zestawiono charakterystyki porównawcze wiatrakowca dla wersji bez usterzenia i z usterzeniem. Po przeprowadzeniu analizy zasugerowano sposób podejścia do optymalizacji geometrii.This paper presents flow simulation results of gyrocopter model without affecting of gyro rotor and propellers. Three-dimensional calculations were performed using the ANSYS Fluent. Based on the calculations the basic aerodynamic characteristics have been made. In addition, the aerodynamic characteristics of gyro version without the tail and the with the tail have been compared. After analyzing the proposals of geometry optimization has been given

CFD simulation study of air flow around the airfoil using the Magnus effect

The article presents a simulation study of air flow around the airfoil equipped with an additional rotary element, using the Magnus effect to change the air flow around it. For this purpose, a two-dimensional computational model for the airfoil without and with the moving element was made. The model was based on the airfoil NACA 8-H-12. The article describes a method of creating a model in two versions: without moving computational grid and with moving computational grid. Studies were carried out for a typical flow rate corresponding to the flow velocity around the gyroplane in a nominal flight speed conditions. Article shows a comparison of flows in both cases, and assesses the impact of the geometry that use the Magnus effect on the work of airfoil

Designing of Wankel engine injection adapter using rapid prototyping method

W artykule przedstawiono proces wytwarzania adaptera wtryskiwaczy silnika Wankla. Zaprezentowano etap projektowania adaptera w systemie CAD (Catia v5) przy użyciu zawansowanych technik komputerowego wspomagania projektowania. Przedstawiono proces wytwarzania adaptera techniką Rapid Prototyping przy użyciu drukarki 3D - ZPrinter 450 oraz zaprezentowano gotowy element wytworzony za pomocą obróbki CNC.The article presents the 3D printing process of a Wankel engine injector adapter. The paper presents the design stage of an adapter in a CAD (Catia V5) by using advanced computer-aided design techniques. Article shows the process of printing an adapter using rapid prototyping technique in 3D Printer - ZPrinter 450. In the end the finished item produced by the CNC is presented

Optimizing the geometry of the connecting rod in opposite pistons engine

The article presents the results of simulations research carried out, using Finite Element Method. The simulations were made in the Abaqus software. Studies were related to the reduction and improving of stress distribution in the connecting rod of opposite pistons combustion engine. The connecting rod has been developed in a 3D environment in the Catia software, then imported into the simulation tool, in which stress tests were performed. The connecting rod was subjected to a compression and stretching tests. Boundary conditions of forces used in simulation tests have been developed on the basis of the dynamic model created in the MSC Adams software. The study included nine iterations of geometric changes of connecting rod. Shape as well as properties such as parametric dimensions (rod length) were changed. The changes were dictated by the reduction of the maximum values of the stresses and the size of the fields with large stress values. As a result of the simulations, the improvement of the connecting rod strength was obtained by its geometrical change (which was obtained by reducing the stress fields)

Modeling the thermal loads in the Subaru EJ25 engine

The research focuses on the solutions to avoid overheating the intake and exhaust valves due to engine overload. Subaru EJ25 engines are currently mounted in passenger cars such as Subaru Impreza but the author's innovative idea is to use them in small passenger airplanes. The paper describes the coupled thermo - mechanical load model of a supercharged Subaru EJ25 engine. The engine piston was tested thermally and mechanically, and the intake and exhaust valves only thermally. The calculations were done using the finite element method (FEM) in ABAQUS 6.10. Parts where divided into Hex and Tet mesh elements, depending of their geometry. The models used in the simulation were previously created using CATIA v5. Because there were only separate parts, the authors used only Part Module. The process of 3D scanning based on the method of reverse engineering was for fine mapping the surface of the examined parts, e.g. a piston. The boundary conditions and material properties are based on the literature and the information provided by the companies that sell spare parts for this engine. The simulations were done for varied heating times and mechanical load (25, 50, 100, 250, 400 seconds)