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Pozycja Basic Study of Synchronization in a Two Degree of Freedom, Duffing Based System(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2015) Dąbrowski, Artur; Mnich, Konrad; Stefański, AndrzejThe issue of synchronization has been analyzed from many points of view since it was first described in 17th century. Nowadays the theory that stands behind it is so developed, it might be difficult to understand where it all comes from. This paper reminds the key concepts of synchronization by examination of two coupled Duffing oscillators. It describes also the origins of Duffing equation and proves its ability to behave chaotically.Pozycja Analytical and Experimental Determination of FML Stiffness and Strength Properties(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2015) Kamocka, Monika; Mania, Radosław J.The paper presents application of analytical methods of determining the mechanical properties of Fibre Metal Laminates. Chosen micromechanical methods were employed to predict elastic moduli and strength of FML panels. Prediction was conducted on two levels i.e. micromechanics where properties of a single composite lamina (prepreg) were analyzed, and macro-mechanics to determine properties of a full FML hybrid material. The properties of a single GFR lamina were predicted by Rule of Mixture Method (ROM), inverse Rule of Mixture Method with correction factor, Halpin Tsai Method, Tsai Method and Wilczynski Method application. Properties of full 3-2 FML lay-up were determined using the Rule of Mixtures. Analytical results were verified by experimental tests. Tensile and bending test were performed on rectangular standard coupons of 3-2 FMLs.Pozycja Implementation of the New Control Methods in Simplification of a Multidimensional Control and Optimization of a Control System Parameters(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2015) Pijanowski, Karol; Dąbrowski, Artur; Balcerzak, MarekThe main purpose of this text is to present application of the Largest Lyapunov Exponent (LLE) as a criterion for optimization of the new type of simple controller parameters. Investigated controller is the part of numerically simulated control system. The calculation of LLE was done with a new method [2]. Introduction contains reference to previous publications on inverted pendulum control and Lyapunov stability. Application of the new simple formula for LLE estimation in control systems is discussed. In the next part simulated dynamical system is described and new type of simple controller allowing to control multidimensional system is introduced. In the last part results of the simulation are shown along with conclusions to whole dynamics analysis. Comparison of the proposed regulator with the linearquadratic regulator (LQR) was verified and its better effectiveness with respect to LQR was proved.Pozycja Fatigue of Steel Plates with Inclusions(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2015) Jaroniek, Mieczysław; Niezgodziński, TadeuszManufactured by the end of the 80s in the last century steel structures were made of steel which contain significant amounts of non-metallic inclusions. As a result of many years of intensive use of the structures made of steel, structural discontinuity material combine to form internal cracks called lamellar cracks. These cracks are formed in rolled sheets with non-metallic inclusions. Studies of lamellar cracks began in the 1960s, but there is still no satisfactory theory explaining their formation.Pozycja Element Birth and Death Method Application to Lamellar Crack Analysis(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2015) Jaroniek, Mieczysław; Niezgodziński, TadeuszLoad structure, the maximum permissible load is usually determined by the strength calculation (bearing data. Yield stress or strength of the material), or the parameters of fracture mechanics. The paper analyzes the calculations lamellar cracks formed in the lower crane girders steel belts. These cracks are formed in rolled sheets of non-metallic inclusions. The determination of the cracks in the existing designs are extremely difficult. It requires testing metallographic, ultrasonic or acoustic methods. Based on typical images of metallographic steel plates specified place of occurrence of cracks lamellar and sampling, and has subsequently been adopted for the calculation of numerical models of material structure and distribution of artificial joints. In order to analyze the propagation of cracks and formation of lamellar phase slots and destruction was carried out modeling studies and numerical methods cracking process.Pozycja Application of the Lyapunov Exponent Based on Current Vibration Control Parameter ( CVC) in Control of an Industrial Robot(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2015) Szaniewski, Mateusz; Dąbrowski, Artur; Balcerzak, Marek; Zawiasa, PiotrControlling dynamics of industrial robots is one of the most important and complicated tasks in robotics. In some works [3, 7], there are algorithms of the manipulators steering with flexible joints or arms. However, introducing them to calculation of trajectory results in complicated equations and a longer time of counting. On the other hand, works [4,5,6]show that improvement of the tool path is possible thanks to the previousidentification of the robot errors and their compensation. This text covers application of Largest Lyapunov Exponent (LLE) as a criterion for control performance assessment (CPA) in a real control system. The main task is to find a simple and effective method to search for the best configuration of a controller in a control system. In this context, CPA criterion based on calculation of LLE by means of a new method [9-11] is presented in the article.Pozycja Performance Improvement through the Vane Clocking Effect in a Two-Stage Impulse Turbine(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2011) Smolny, Antoni; Błaszczak, Jarosław; Sobczak, KrzysztofThe paper describes the experimental and numerical investigations of stator clocking effects on performance of a two-stage impulse turbine with low-aspect ratio airfoils. The data present the clocking effect that can be observed both for local flow patterns and external characteristics for the entire turbine in terms of efficiency. Finding an optimal relative circumferential position of stators in a multistage axial turbine has been the subject of extensive investigations in the last decade.Pozycja Multilevel Optimization of the Semi-Open Impeller in a Centrifugal Pump(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2011) Papierski, Adam; Błaszczyk, AndrzejFull optimization task for the case of the semi-open impeller with straight blades, requires description of its' geometry by means of, at least, eighteen design variables. In the case of constant meridional cross-section, are required at least eight design variables. Solution of the task with such great vector of design variables requires much more time. One way to manage to obtain a solutions with great variety of design variables is comprehensive approach to the task depending on the partition into minor subtasks. After decomposing the optimization task, one should choose procedure of solving it. One of these procedures is parametric optimization, which is two-stage method of minimizing (maximizing). This optimization is carried on in two levels. On a lower level, multi-optimization of decomposed parts of the tasks, depending on design variables, is being held. The solution of the lower level is used in an upper level (coordinating level) to find optimal coordination variables. It has been shown that result of multilevel optimization and full task optimization is the same in limits of accepted accuracy of the objective functions' calculus. Time of the calculation for the multilevel optimization task is over four times shorter than undecomposed task time.Pozycja Investigations of Oil-Free Support Systems to Improve the Reliability of ORC Hermetic High-Speed Turbomachinery(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2011) Tkacz, Eliza; Kozanecka, Dorota; Kozanecki, Zbigniew; Miazga, KacperThe design of a small turbo-generator to produce electricity in the range from a few kWs requires the use of an aerostatic or aerodynamic gas bearing system. The theoretical analysis and the experimental test at the present stage of the study show that such highly rotating constructions are feasible. The problem consists in the optimal design selection from the viewpoint of the machine reliability and the adjustments are connected to the diminution in static thrust and lateral loads of the bearings by a correct design of the turbine flow structure and a correct selection of the gas bearing type.Pozycja Modernization of a Nitrous Gas Turbine-Driven Turbocompressor(Wydawnictwo Politechniki Łódzkiej ; Katedra Dynamiki Maszyn - Wydział Mechaniczny Politechniki Łódzkiej, 2011) Kryłłowicz, Władysław; Kozanecki, Zbigniew; Świder, PiotrThe modernization of a nitrous gas four-stage centrifugal compressor is presented. The assumptions for modernization, its methodology and the results of thermodynamical, flow and dynamical calculations have been discussed. The technological aspects of the rotor modernization have been given.