Temat: propulsion system vibrations - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Kinematic of marine piston-crankshaft system
Autorzy:: Murawski, L.
Powiązania:: https://bibliotekanauki.pl/articles/246452.pdf
Data publikacji:: 2015
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: marine propulsion system
piston-crankshaft kinematic
slow speed engines
inertia forces
propulsion system vibrations
Opis:: Two-stroke, slow speed main engines are often installed on merchant ships, because of its very high efficiency. That kind of engine has an output of about 5500 kW per cylinder. The mass of piston-crankshaft system reaches over a dozen tons. That reciprocating masses are source of high level of dynamic inertia forces (mass forces). Those forces have big influence on engines working parameters and characteristics. One of them is instability of crankshaft rotational speed, which leads to dangerous torsional vibrations of propulsion system. Some inconsistency can be observed during analysis of piston-crankshaft system kinematic. In the theoretical engine books, the piston speed and acceleration has only two harmonic components, the inertia forces are depended on engine rotation speed and they doubled rotation speed. However, empirical formulas, published by engines producers, give us at least five harmonic components of mass forces. The author tries to find out the theoretical reason of existing (measured) higher harmonic orders of engines inertia forces. It is a first step for developing monitoring system of propulsion system’s torsional vibrations coupled with axial vibration, dynamic shaft line alignment and crankshaft springing. In the paper two analytical methods of piston displacement, speed and acceleration are presented. Well-known (from literature) equations are compared with more-detailed analytical procedures. The analysis was performed for one of the biggest marine MAN B&W engine, type 7K98MC. A discussion about the analysis results was included in the final part of the paper.
Źródło:: Journal of KONES; 2015, 22, 2; 155-162
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 2.

Tytuł:: Diagnostic of the piston rod gland’s failure of marine slow speed main engine
Autorzy:: Murawski, L.
Van Doan, D.
Powiązania:: https://bibliotekanauki.pl/articles/244395.pdf
Data publikacji:: 2017
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: marine propulsion system
slow-speed main engine
failure of piston-crankshaft system
diagnostic based on vibrations
displacement
stress level
Opis:: The article presents untypical diagnostic of the slow-speed, marine main engine. The engine was newly made-up and checking during mounting process and during sea trial. However, a leak under piston chamber of second cylinder along the piston rod appeared few days after the sea trial. The stuffing box exchange (with the piston rod’s regeneration) did not give expected results − the failure happened again. All geometrical and exploitation parameters was in acceptable range. The ship with main engine was fifth in the series of sister ships. The authors were asked for urgent expert opinion. Mix of different measurements was planned after formulation several hypothesis. Displacements of piston rod and cylinder, a stress level of main engine body, and vibrations level in different points of main engine was performed during short sea voyage. Not a single hypothesis can be considered as the main cause of the failure. It turns out, that a serious failure need not be caused by a single reason. According to snowball theory a sum of small effects, each of them affecting slightly the engine operation, can be a cause of serious failure. In the authors’ opinion, the failure was caused by a sum of relatively slight effects. The probably scenario of the failure process was enunciated. The recommendation for the engine project was formulated: some of the geometrical tolerances should be changed.
Źródło:: Journal of KONES; 2017, 24, 4; 203-210
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 3.

Tytuł:: Forces exciting vibrations of ships hull and superstructure
Autorzy:: Murawski, L.
Powiązania:: https://bibliotekanauki.pl/articles/259533.pdf
Data publikacji:: 2005
Wydawca:: Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:: hull vibration
superstructure vibration
main engine vibrations
excitation forces
pressure pulses
propulsion system's reactions
crankshaft-propeller phasing
Opis:: The paper presents identification of main excitation forces ofvibrations of ship hull and its superstructure, as well as investigation of influence of the analyzed excitation on ship vibration level. The following excitation forces were analyzed: dynamic pressure on the transom deck, propeller-generated hydrodynamic forces, as well as internal and external engine-generated forces. Rigidity and attenuation characteristics of lubricating oil film were taken into account in the analysis of the excitations transmitted by the propulsion system bearings (stern tube bearing, intermediate bearing, engine s main and thrust bearings). The dynamic characteristics of ship's power transmission system were also taken into account.Results of the analyzes were verified by comparing results of the computations and measurements.
Źródło:: Polish Maritime Research; 2005, 4; 15-21
1233-2585
Pojawia się w:: Polish Maritime Research
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 4.

Tytuł:: Vibrations in Marine Power Transmission System
Drgania okrętowych układów przeniesienia napędu
Autorzy:: Doan, D.
Murawski, L.
Powiązania:: https://bibliotekanauki.pl/articles/342083.pdf
Data publikacji:: 2017
Wydawca:: Uniwersytet Morski w Gdyni. Wydawnictwo Uniwersytetu Morskiego w Gdyni
Tematy:: marine propulsion ship vibrations
torsional vibration
marine propulsion system
finite element method
drgania okrętowych układów napędowych
drgania skrętne
okrętowe układy napędowe
metoda elementów skończonych
Opis:: Vibration analyses of marine machines and structures are one of the most important during the design process as well as during exploitation. Vibrations of ship hull (including superstructure and main engine body) are separately analysed from the vibrations of power transmission system. Vibrations of propulsion system include three types: lateral vibration, coupled axial vibration and torsional vibration. Among them, torsional vibrations are usually the most dangerous for the shaft line and the crankshaft. These vibrations may cause the increasing failure of the engine crankshaft as broken and bent shaft. Therefore, this article focuses on the study of torsional vibration of ship propulsion system. Calculation of torsional vibration of propulsion system with a medium-speed main engine is presented. The analysis is based on finite element method, with the code written in Matlab software. The result of this paper is applied for the tugboat with the engine of power 350 HP.
Analizy drgań okrętowych maszyn i konstrukcji są jednymi z najważniejszych podczas procesu projektowania oraz ich eksploatacji. Drgania kadłuba statku (z nadbudówką i korpusem silnika głównego włącznie) są analizowane oddzielnie od drgań układu przeniesienia napędu. Wyróżnia się trzy typy drgań układu napędowego: drgania giętne, sprzężone wzdłużne oraz skrętne. Wśród nich drgania skrętne są zwykle najgroźniejsze dla linii wałów wału korbowego. Mogą one zwiększyć prawdopodobieństwo uszkodzenia wału korbowego poprzez jego złamanie lub wygięcie. Z tego powodu w artykule skupiono się na analizie drgań skrętnych okrętowych układów napędowych. Zaprezentowano obliczenia drgań skrętnych układu napędowego wyposażonego w średnioobrotowy silnik główny. Analizę przeprowadzono metodą elementów skończonych, której procedura została napisana w programie Matlab. Zastosowano ją do obliczeń holownika wyposażonego w silnik o mocy 350 HP.
Źródło:: Zeszyty Naukowe Akademii Morskiej w Gdyni; 2017, 100; 37-50
1644-1818
2451-2486
Pojawia się w:: Zeszyty Naukowe Akademii Morskiej w Gdyni
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Informacja

Wyszukujesz frazę "propulsion system vibrations" wg kryterium: Temat

Źródło danych

Dostawca treści

Kolekcja

Rok wydania

Wydawca

Temat

Autor

Typ dokumentu

Język