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EN
The article presents assumptions of the one-dimensional model of the ASz-62IR aircraft engine. This model was developed in the AVL BOOST software. The ASz-62IR is a nine cylinder, aircraft engine in a radial configuration. It is produced by the Polish company WSK “PZL-Kalisz” S. A. The model is used for calculating parameters of the fuel stream and the air stream in intake system of the engine, as well as for the analyses of the combustion process and the exhaust flow to the external environment. The model is based on the equations describing the isentropic flow. The geometry of the channels and all parts of the model has been mapped on the basis of empirical measurements of the engine elements. The model assumes indirect injection where the gasoline was used as a fuel with the calorific value of 43.5 MJ/kg. The model assumes a mixture of a stoichiometric ratio of 14.5. This model is only part of the overall the ASz-62IR engine model. After the simulation tests on the full model the obtained results confirmed the correctness of the model used to create the mixture. It was found that the AVL BOOST software is good for the implementation of this type of work.
PL
W artykule przedstawiono założenia jednowymiarowego modelu wymiany ładunku z silnika lotniczego ASz-62IR. Model ten został opracowany w programie AVL BOOST. Silnik ASz-62IR jest dziewięciocylindrowym silnikiem lotniczym w układzie gwiazdy. Jest on produkowany przez polską firmę WSK „PZL-Kalisz” S.A. Opracowany model służy do obliczania parametrów strumienia paliwa i powietrza w układzie dolotowym silnika, jak również do analizy procesu spalania i przepływu spalin do środowiska zewnętrznego. Model jest oparty na równaniach opisujących przepływ izentropowy. Geometrię kanałów i wszystkich przepływowych elementów modelu odwzorowano na podstawie empirycznych pomiarów konstrukcji silnika. W modelu założono wtrysk pośredni, a jako paliwo zastosowano benzynę o wartości opałowej 43,5 MJ/kg. Założono stechiometryczną mieszankę o współczynniku 14,5. Opisany model jest tylko częścią całkowitego modelu silnika ASz-62IR. Po wykonaniu badań symulacyjnych pełnego modelu uzyskano wyniki potwierdzające prawidłowość zastosowanego modelu tworzenia mieszanki oraz stwierdzono przydatność oprogramowania AVL BOOST do realizacji tego typu prac.
EN
The paper describes the application of the author's mathematical model of gas-dynamic processes for a marine piston engine based on a computer program. The developed mathematical and numerical model is designed to conduct simulation diagnostics. Therefore, it is possible to carry out calculations for motors in different technical conditions and observing influence of changes in technical condition on selected parameters of its work. Simulation of changes in technical condition is carried out by modifying parameters of structure’s model object. The article contains a detailed description of each options of the computer program. From the main program window, user can select type of engine model (supercharging method, cylinder number, work order, stroke and piston diameter and a number of other parameters). Through a window of simulation of known and recognizable damages such as: change in fuel dose for each cylinder, change in intake and outlet valves, leakage of piston-ring-cylinder system, change of injector hole cross section. Final windows show results of calculations in form of mileage parameters of engine as a function of crank angle.
EN
The work presents a model of the marine diesel engine working process. The research object was the AL25/30 engine. The model consists of partial models of the combustion process in the engine cylinders, the heat exchange process, flows through air and exhaust channels, heat exchange in the intercooler and friction in mechanical components of the engine. The model includes a description of the processes taking place in the turbocharger also. The input data to the model and the verification data were the results of direct measurements on the research facility. The verification showed errors in the calculation of air and exhaust gas parameters not exceeding 11%. The paper also presents an analysis of the results of fast-changing parameters, including combustion pressure in engine cylinders and pressures in individual gas channels. The designed model allows the analysis of the research facility operation and enables its further development towards the assessment of toxic compounds emission to the atmosphere.
4
Content available remote Mathematical model and simulator of rotor with vibrating blades
EN
The paper presents description of rotating bladed disk mathematical model. Correctly defined mathematical model of rotor allows creation of numerical simulation model which can be used to generate tip-timing data. First of all, the model is necessary to conduct a research on blade response due to input force in form of changing rotational speed. This enables the possibility to determine turbojet engine terminal operating conditions causing its failure.
PL
Tematem publikacji jest opis modelu matematycznego ułopatkowanej tarczy stopnia wirującego silnika odrzutowego. Poprawnie stworzony model matematyczny wirnika pozwala na stworzenie modelu symulacyjnego, który może posłużyć do generowania danych tip-timing. Przede wszystkim jest on potrzebny do badania odpowiedzi łopatek wieńca wirnikowego na wymuszenie w postaci zmian prędkości obrotowej silnika. Pozwala to na określenie warunków pracy silnika odrzutowego, dla których mogło by nastąpić jego uszkodzenie.
EN
Stoichiometric air-to-fuel ratio (lambda) control plays a significant role on the performance of three way catalysts in the reduction of exhaust pollutants of Internal Combustion Engines (ICEs). The classic controllers, such as PI systems, could not result in robust control of lambda against exogenous disturbances and modeling uncertainties. Therefore, a Model Predictive Control (MPC) system is designed for robust control of lambda. As an accurate and control oriented model, a mean value model of a Spark Ignition (SI) engine is developed to generate simulation data of the engine's subsystems. Based on the simulation data, two neural networks models of the engine are generated. The identified Multi-Layer Perceptron (MLP) neural network model yields small verification error compared with that of the adaptive Radial Base Function (RBF) neural network model. Consequently, based on the MLP engine's model, the MPC system is performed through a nonlinear constrained optimization within gradient descent algorithm. The performance of the MPC system is compared with that of a first order Sliding Mode Control (SMC) system. According to simulation results, the tracking accuracy of lambda by the MPC system is close to that of the SMC system. However, the MPC system results in considerably smoother injected fuel signal.
PL
W artykule przedstawiono podstawowe pojęcia teorii wrażliwości. Omówiono metodę analizy wrażliwości całkowitej zastosowaną do oceny istotności wielkości wejściowych w badaniach identyfikacyjnych modelu silnika. Podano przykład zastosowania metody wrażliwości do wyznaczenia funkcji modelu współczynnika napełnienia.
EN
In the present paper basic notations of the sensitivity analysis have been presented. A total sensitivity analysis method, basing on global regression model, has been presented. This method has been used to assess the significance of the factors in the research engine model identification. An example application of this method to determine the model sensitivity of the filling ratio.
EN
In the paper an optimization procedure concerning a construction of a 6/4 type SRM has been described. A magnetically linear analytical model derived with the help of a reluctance network method has been employed in this task. The model allows determining all quantities required in a design synthesis program. A sensitivity analysis has been performed for two criterial functions related to an average value of the electromagnetic torque and the rated efficiency, with respect to one of the optimization variables, as well as an assumed value of the rated velocity. An example of optimization concerns a minimization of the amplitude of the pulsating component of the electromagnetic torque. Optimization results are presented and validated by means of a magnetically non-linear FEM model. After some modifications the presented approach can be applied when searching for a best construction of any type SRM, in particular for a drive motor in an electrical vehicle.
EN
The paper presents a model for simulating the influence of a voltage phase shift on the emf and dynamic states an induction motor. The model was employed to simulation investigation of both the balanced and unbalanced voltage dip and the voltage phase shift in the subsequent voltage recovery and the voltage phase shift without voltage dip. The observation of the emf provides information about the influence of the field suppression rate on the dynamic performance of a motor after the voltage recovery. The influence of the voltage phase shift on the motor operation was analysed for various values of the moment of inertia and the motors loads. The equations describing the electromechanical conversion in an induction motor are based on the Hamilton's principle of least action and Euler-Lagrange equations. Equations of the induction motor dynamics are written for the sinusoidal, three-phase stator supply voltage, in the stator-fixed coordinates for the space vectors components (a,b) of voltages U , currents i and the electromotive force E. The simulation was carried out using the Matlab package.
EN
Existence of parasitic torques in induction motors is their disadvantage. The torques causes noise and vibrations. They also can cause difficulties with start of motor. One of methods of their elimination is usage of additional ring in the middle of rotor and proper turning of created rotor's halves. In following article mathematical model of squirrel-cage induction motor with additional ring is given. The principle of operation of additional ring is cleared and there are also some interesting simulation results proving possibility of reducing parasitic torques by additional ring.
PL
Występowanie zjawisk pasożytniczych w maszynach indukcyjnych jest jedną z ich wad. Momenty pasożytnicze powodują zwiększony hałas i wibracje. Mogą również powodować problemy podczas rozruchu silnika. Jest wiele metod eliminacji tych momentów, a jedna z nich to użycie dodatkowego pierścienia zwierającego w środku pakietu wirnika wraz z odpowiednim skręceniem, względem siebie, powstałych w ten sposób połówek wirnika. Artykuł przedstawia model matematyczny indukcyjnego silnika klatkowego z prostymi żłobkami i dodatkowym pierścieniem zwierającym w wirniku sformułowany przy pewnych założeniach upraszczających. Wyjaśniono zasadę działania pierścienia dodatkowego oraz ukazano wybrane wyniki symulacji przeprowadzonych na opisanym modelu, dowodzące redukcji momentów pasożytniczych przy pomocy pierścienia dodatkowego.
PL
Artykuł ujmuje 3-fazowy model silnika uwzględniający impedancje pasożytnicze pomiędzy uzwojeniem stojana a rdzeniem stojana i wirnika. Przedstawiono metodę wyznaczania tych impedancji oraz wyniki pomiarów sprawdzających poprawność przyjętego modelu silnika. Porównano wybrane przebiegi otrzymane z układu symulacyjnego i z pomiarów.
EN
In the paper a three-phase motor model with parasitic coupling impedances between the stator winding and the stator and rotor cores is presented. The method for determining these impedances and the results of measurements verifying the motor model are given. The chosen simulation results are compared with those obtained from measurements.
11
Content available remote Polowo-obwodowy model obliczeniowy silników synchronicznych reluktancyjnych
EN
The paper presents the way of calculating the exploitation parameters of a 3-phase synchronous reluctance motor with a rotor based on a squirrel cage one when taking into account saturation of a magnetic circuit. The finite element method for a 2D problem is used in field calculations. Basing on them the characteristics of flux linkages in relation to the stator current space phasor are determined. These characteristics used in circuit calculations allow determining the motor exploitation parameters in steady states. The calculated angular characteristics of electromagnetic torque show that there is the necessity of taking into account saturation of a magnetic circuit. The results of field calculations of a motor starting torque in relation to the rotor position are presented as well. The calculation results are compared with the available measurement results.
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