Temat: rotor - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Gyroplane rotors vibration tests
Autorzy:: Wojtas, M.
Trendak, M.
Tematy:: rotor vibration
rotor blades
teetering rotor
hub connector
rotor imbalance; Pokaż więcej
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Powiązania:: https://bibliotekanauki.pl/articles/246317.pdf Link otwiera się w nowym oknie
Opis:: The article presents vibration test of three different types of gyroplane main rotors. The test was carried out on a specially prepared test bench using a Red Led Tacho Sensor measuring system. Tests were conducted for the project „Research and development works on innovative construction of aircrafts of weight over 560 kilograms at the company Trendak Aviation”. The work outlines the basic properties of the gyroplane vibration and gives their sources. The research focused on the gyroplane main rotor vibration related inter alia to the rotor imbalance as well as rotor hub connector construction. Tested rotors consisted of three different types of gyroplane rotor blades and innovative universal hub connector with positive coning angle of 2.8º. The article summarized the basic properties of three types of gyroplane the rotor blade, marks advantages of use hub connector witch constructional dihedral angle. Discusses the principle of operation of measuring device, tests methodology starting from instrument calibration. The results of the measurements are shown in the graphs in polar coordinates. The vibration measurement is carried out in two axes, in x-axis, longitudinal, along the rotor radius and in y-axis, perpendicular to the x-axis, in the direction of the chord of the rotor blades.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 2.

Tytuł:: Comparison of higher harmonic contents in salient pole synchronous generator with different rotor construction
Autorzy:: Ludwinek, K.
Nadolski, R.
Staszak, J.
Tematy:: salient pole synchronous generator
higher harmonics
solid rotor
rotor with radial incisions
laminated rotor; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/140521.pdf Link otwiera się w nowym oknie
Opis:: The paper presents a comparison of higher harmonics in induced phase voltages of a stator winding in the no-load state of a three-phase 5.5 kVA salient pole synchronous generator. The comparison is carried out for the synchronous generator with different salient pole rotor constructions: a non-skewed solid rotor, a non-skewed solid rotor with radial incisions, and a laminated electrotechnical steel rotor with skewed slots and damping bars. The calculations of higher harmonics are based on the magnetic field distributions in the air gap, which are carried out in a 2D model in a FEMM program and on the induced voltage waveforms in the stator windings registered during experimental investigations of the 5.5 kVA salient pole synchronous generator in the no-load state.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 3.

Tytuł:: New gyroplane hub connector with positive coning angle
Autorzy:: Wojtas, M.
Trendak, M.
Tematy:: blade dihedral angle
waving
rotor instability
teetering rotor; Pokaż więcej
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Powiązania:: https://bibliotekanauki.pl/articles/244662.pdf Link otwiera się w nowym oknie
Opis:: The article presents advantages and disadvantages of two blade teetering rotors with constructional dihedral angle greater than 0o . Several structural design solutions of rotor hub connector are shown in this work. However, the main attention is focused on innovative hub connector design and manufactured by Trendak Aviation Company during the project “Research and development works on innovative construction of aircrafts of weight over 560 kilograms”. Discusses structural advantages of the new rotor hub connector according to other construction. Also were raised issues related to the load of the gyroplane rotor during the flight, in particular the load of rotor blades root, during a gyroplane break manoeuvre, according to conning angle of rotor hub connector. The disadvantages of using the structural dihedral angle in teetering rotors are also presented, focusing on the rotor aeroelastic instability so-called waving, which from the literature analysed is concerned only with two blades teetering rotors. Performed a coarse analysis in SMOG program, prepared at the Institute of Aviation for the analysis of helicopter and gyroplanes rotors. The stability analysis of the rotor for a number of structural dihedral angle and blades setting pitch was performed. Basis of this analysis the stability boundary were determined for the analysed gyroplane rotor with connector hub with positive coning angle of 2.8o. .
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 4.

Tytuł:: Vibration of a mistuned three-bladed rotor under regular and chaotic excitations
Autorzy:: Warminski, J.
Latalski, J.
Szmit, Z.
Tematy:: rotating beam
multi-bladed rotor
rotor mistuning
chaotic oscillations; Pokaż więcej
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Powiązania:: https://bibliotekanauki.pl/articles/280551.pdf Link otwiera się w nowym oknie
Opis:: This study considers forced vibrations of a rotating structure consisting of a rigid hub and three flexible beams. The blades are nominally made of a multilayered laminate with a specific stacking sequence resulting in full isotropic macroscopic material behaviour. However, in the performed analysis it is assumed that the rotor has been mistuned because of manufacturing tolerances of the composite material. These inaccuracies are represented by deviations of reinforcing fibres orientations from their nominal values. The considered tolerances break the intended macroscopic material isotropy and make the laminate to exhibit the fully orthotropic behaviour. Based on previous authors research, the system of four mutually coupled dimensionless ordinary differential governing equations is adopted. Forced responses of the system under regular and chaotic excitations are investigated.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 5.

Tytuł:: Analysis of technological process of installation turbochargers
Autorzy:: Cygnar, M.
Mazurków, A.
Jaskólski, J.
Tematy:: turbocharger
installation of turbocharger's group
turbine's rotor
compressor's rotor; Pokaż więcej
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Powiązania:: https://bibliotekanauki.pl/articles/244108.pdf Link otwiera się w nowym oknie
Opis:: The technological process of installation of turbocharger as well as detailed analysis of chosen stages of installation having fundamental influence on the correct work of the turbocharger are presented in the article. The purpose of this article is performance of whole process of installation turbocharger as well as analysis of particularly significant stages of this process. The creature of turbocharging and it is myself this of working of turbocharger is enough simple. Difficulties appear if we put to the analysis conditions work of turbocharger: high temperature offumes, variable loads, aggressive environment of combustion gases, high rotatory speeds of rotors. Some of exploitation problems are possible to the elimination on the design stage or by means of application of appropriate materials. However technological process of installation is responsible for output quality and failure-free lasting work of turbocharger. In the process of installation it can distinguish some essential stages: processing and installation of shaft with the turbine's rotor, the weighing of turbine's rotor and the compressor, the installation of rotor's group, weighing of rotor's group in the trunk, positional tests under load. High rotary speeds cause during work of rotator so that created during of installation of turbocharger inappropriate balancing can bring to important damages of turbocharger. The correct course of process of installation and the final verification on braked position allows to avoid most of breakdowns of turbocharger group as well as to ensure long term of correct exploitation.From this reason very important is detailed analysis of respective stages of installation of group.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 6.

Tytuł:: Analiza modalna i harmoniczna modelu zespołu elektrowibratora przy różnej konfiguracji ciężarów
Modal and frequancy analysis kit electrovibrator for different configuration of activators
Autorzy:: Madej, J.
Sitek, M.
Tematy:: analiza drgań
analiza
wirnik
analysis
rotor
rotor vibration; Pokaż więcej
Wydawca:: Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Powiązania:: https://bibliotekanauki.pl/articles/386701.pdf Link otwiera się w nowym oknie
Opis:: W niniejszym opracowaniu przedstawiono analizę częstotliwości drgań własnych i analizę harmoniczną zespołu wirnika wibratora elektrycznego. Otrzymane wyniki posłużą do optymalizacji poszczególnych elementów elektrowibratora, a w szczególności kształtu ciężarków oraz łap elektrowibratora, które często ulegają uszkodzeniu podczas pracy całego urządzenia. Znajomość maksymalnych wartości przemieszczeń ciężarków pozwoli z kolei na optymalizację kształtu osłony elektrowibratora.
This paper presents modal analysis and frequency analysis rotor kit of three-phase induction rotating electrovibrator. The received solutions will be use for optimization parts of electrovibrator, especially shape activators and foots of electrovibrator, it's often brake down. The knowledge about maximum translation of activators will be helpful for optimization of iron activator cover.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 7.

Tytuł:: Interferencja wirnik nośny - wirnik ogonowy
Interference between the main and tail rotors
Autorzy:: Łusiak, T.
Tematy:: interferencja
wirnik nośny
wirnik ogonowy
interference
main rotor
tail rotor; Pokaż więcej
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Lotnictwa
Powiązania:: https://bibliotekanauki.pl/articles/212441.pdf Link otwiera się w nowym oknie
Opis:: W artykule przedstawiono modele zaburzeń opływu śmigłowca w płaszczyźnie wirnika ogonowego wywołanych bliskością wirnika nośnego. Przedstawiono model śladu zawirnikowego w oparciu o zasadę Biota i Savarta w celu określenia zaburzeń pola prędkości indukowanej przez wirnik nośny w płaszczyźnie wirnika ogonowego [4].
The influence of disturbances to the flow around a helicopter resulting from a resultant reaction of the wake from the main rotor on the tail rotor, on the loading as well as control and noise of the helicopter was presented. The analysis was based on a rotational model of the system. The basis of the model of the interference is the replacement of wake generated by rotors and fixed lifting surfaces by a uniform rotational model in the form of discrete rotational grids. This allows for the integration of fields induced through all rotational elements of the system, in accordance with the Biot-Savart law. This law was accepted in view of the fact that, as the only law included in the flow model, it enables a constant processing of load calculations in an undefined flight, with the retention of a reasonable calculation time. The undertaking of this subject should help explain phenomena not completely recognized and which exert a significant influence on safety when operating helicopters certain states of flight. The results of modeling, carried out for the SW4 helicopter, contain an evaluation of disturbances of the field of flow around the tail rotor in given states of flight, in which the case of take-off in a sidewind and with the carrying out of a directional maneuver is of primary significance. In other cases, when the tail rotor does not enter into intensive disturbances of the velocity field by the main rotor, the interference phenomena are of lesser importance. The numerical program used allows for information about flow around and loads on the taił rotor in flow disturbed by the (main) rotor to be obtained. Resultant loads on the tail rotor can be evaluated, along with its chosen elements.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 8.

Tytuł:: Numerical simulation of model helicopter rotor in hover
Autorzy:: Doerffer, P.
Szulc, O.
Tematy:: transonic
hover
helicopter rotor; Pokaż więcej
Wydawca:: Politechnika Gdańska
Powiązania:: https://bibliotekanauki.pl/articles/1943245.pdf Link otwiera się w nowym oknie
Opis:: The article presents details of a URANS simulation of the flow field near a hovering model of the Caradonna and Tung (1981) helicopter rotor [1]. The CFD code SPARC [2] proves to be capable of capturing the aerodynamics of a two-bladed rotor in high-speed transonic hover conditions. A comparison of the simulation results with the experimental data is acceptable, hence the described methodology might be used with confidence in future numerical studies of application of noise-reducing devices on helicopter blades.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 9.

Tytuł:: Anomaly of rotor dynamics in ultra-light helicopter – Robinson R22
Autorzy:: Sobieszek, Agnieszka
Tematy:: rotor hub
Robinson R22
helicopter
pull-up manoeuvre
rotor dynamics; Pokaż więcej
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Powiązania:: https://bibliotekanauki.pl/articles/242430.pdf Link otwiera się w nowym oknie
Opis:: The article presents the analysis of anomaly of rotor dynamics in ultra-light helicopter - Robinson R22. Robinson R22 is two-seat, two-blade main rotor and single-engine helicopter, well known as simple and common used aircraft because of low price and high availability. At the same time, large number of accidents and strictly defined rules (recommended piloting technique) and weather condition for safe flight show disadvantages of Robinson R22. The reason for considering this topic is the analysis of different flight properties and helicopter behaviour as well as easy entering into dangerous flight manoeuvre. In the article different flight properties and loss of control during the pull-up, manoeuvre or vertical gusts of wind and mast bumping accidents were analysed. Analysis shows that problem may be caused by construction of three-hinged rotor hub, designed and patented by F. Robinson. Article presents model of rotor hub and review of main rotor and rotor hub construction in light helicopters. Because of number of accidents, caused by the unusual behaviour of Robinson R22, restrictive pilotage rules were introduced: prohibition of flight in certain weather conditions, the necessity of attending additional training conducted by trained instructors. To reduce the probability of an accident a special instruction for specific Robinson R22 properties was created. Moreover, the statistics of accidents resulting from loss of control and review of legal changes caused by Robinson R22 accidents are presented.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 10.

Tytuł:: Parametrization of the main rotor and working environment for different flight conditions – Computational Fluid Dynamics analysis as an application for multidisciplinary optimization
Autorzy:: Kocjan, Jakub
Kachel, Stanisław
Rogólski, Robert
Tematy:: helicopter
main rotor
rotor blade
geometric modelling
computational fluid dynamics
CFD; Pokaż więcej
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Powiązania:: https://bibliotekanauki.pl/articles/59256801.pdf Link otwiera się w nowym oknie
Opis:: The paper shows a method of aerodynamic modelling of the whole rotor and exemplary results obtained from complex analyses. The analytical basis of rotor aerodynamics for different phases of the helicopter flight is shown. The analytical calculations are provided to model a single blade motion according to its azimuth angle and to validate the obtained results. The parametric design method is shown to be applied for different blade planform shapes and various section airfoils. The Computational Fluid Dynamics (CFD) fluid domain for the flow around the blade is also prepared using a parametric method. The parametric graphic script is developed to create the flow domain for a one-blade simulation or for a complete n-bladed rotor effect. The obtained blade model with enclosure is implemented into CFD environment. The method for fluid mesh preparation and the way of defining its properties are given. The simulation is carried out as transient for the n-bladed rotor. In this simulation, various flight conditions are taken into account. Real rotary motion of the blades is simulated with artificially enforced mesh motion. The obtained numerical results are compared then with analytical assumptions. The simulation findings which are the inputs for further analysis are shown with graphical representations. As an output of the research, new options for main rotor optimization are developed. The usage of combined parametric modelling confirmed with aerodynamic analysis for different flight conditions is shown in the work as a new perspective for design optimization of the main rotor.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Informacja

Wyszukujesz frazę "rotor" wg kryterium: Temat