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1

Diagnostics of the internal combustion engines operation by measurement of crankshaft instantaneous angular speed

Dereszewski Mirosław, Sikora Grzegorz

Journal of KONBiN

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2019

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Vol. 49, iss. 4

281--295

EN

Diagnostics based on measuring of crankshaft instantaneous rotational speed allows precise location of damage to the injection system and detection of external disturbances. Active measurement of instantaneous rotational speed requires use of equipment with high sensitivity, permanent assembly at the ends of the crankshaft and the analysis of a very large amount of data. Presented method can be used for measurement of torsional vibration of crankshaft, indirectly through simultaneous measurement of the width of the pulses generated by the encoder disks. Momentary, relative displacement of both disks determines the angle of temporary crankshaft twisting. This paper presents first results of pulse width measurement, obtained by using described system.

PL

Diagnostyka metodą pomiarów chwilowej prędkości obrotowej wału korbowego umożliwia precyzyjną lokalizację uszkodzeń układu wtryskowego oraz wykrywanie zakłóceń zewnętrznych. Aktywny pomiar chwilowej prędkości obrotowej wymaga zastosowania aparatury o dużej czułości, trwałego montażu na końcach wału korbowego oraz analizy bardzo dużej ilości danych. Przedstawiona metoda może posłużyć do obliczania drgań skrętnych wału korbowego pośrednio poprzez symultaniczny pomiar szerokości pulsów generowanych przez tarcze enkoderów. Chwilowe, względne przemieszczenie obu tarcz określa kąt chwilowego skręcenia wału korbowego. W artykule przedstawiono wyniki pierwszych pomiarów szerokości impulsów, uzyskane na opisanym stanowisku badawczym.

2

Processing of long lasting signals of torsional vibrations measured using incremental encoders

Dereszewski M., Sikora G.

Journal of KONES

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2018

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Vol. 25, No. 4

59--65

EN

The article describes processing method of a signal, coming from torsional deflections of an internal combustion piston engine’s crankshaft, registered using two optical encoders ETNP-10. Standard measurement and recording set ETNP-10 enables recording of Instantaneous Angular Speed values encompassing 10 revolutions of the crankshaft, what is equal to 5 cycles of four-stroke engine. That time duration is sufficient for analysis of changes of angular speed caused by, for example, malfunction of fuel injection valve, but is insufficient in case of observation characterized by low frequency changes with period of fluctuations, lower than 0.8 sec. Short time for recording makes impossible following of instantaneous angular speed deviations caused by magnitude modulation of engine’s load value. In the article is presented an algorithm written in MATLAB environment, which allows processing of the data recorded using the recorder DAS 1600 Sefram. The recorded this way signals have around 26 seconds' duration of engine work. Data acquired from two encoders mounted at opposite sides of the shaft, in form of square magnitude signals are transformed into instantaneous speed and subsequently to instantaneous angular shift, what is basis for torsions calculation. In the article is also presented method of elimination of systematic error due to assumed method of averaging. Finally, some examples of results of torsional deflection measurement and analysis are presented.

3

Diagnostic aspects of a crankshaft torsional oscillations monitoring by IAS measurement

Dereszewski M.

Journal of KONES

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2018

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Vol. 25, No. 1

67--74

EN

Continuous monitoring of diesel engine performance under its operating is critical for prediction of malfunction development and subsequently functional failure detection. Analysis of Instantaneous Angular Speed (IAS) of the crankshaft is considered as one of non-intrusive and effective method of detection of combustion quality deterioration. The article contains presentation of attempt of monitoring of piston engine’s crankshaft torsional vibrations by measurement of Instantaneous Angular Speed at free, and power output ends of the engine’s crankshaft. The angular speed measurements was done using two optical sensors for reading the IAS, mounted at shaft line’s opposite ends, one at free end of the crankshaft and second at end of generator’s shaft. In the article is presented description of the measurement system and explanation of its mode of work. Experiments were based at two kinds of malfunction possible to be simulated at test bed. First one was simulation of a leak of fuel injection pump, the second one relayed on mounting of sets of injection valves with different nozzles characteristics (spraying nozzle angle), giving different parameters of fuel injection. Presented results of experiment derives from test cycle carried out using laboratory stand of Gdynia Maritime University equipped with 3- cylinder self − ignition engine, powering electric generator.

4

Monitoring of torsional vibration of a crankshaft by instantaneous angular speed observations

Dereszewski M.

Journal of KONES

|

2016

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Vol. 23, No. 1

99--106

EN

Continuous monitoring of diesel engine performance under its operating is critical for prediction of malfunction development and subsequently functional failure detection. Analysis of Instantaneous angular Speed (IAS) of the crankshaft is considered as one of non-intrusive and effective method of detection of combustion quality deterioration. The paper contains presentation of attempt of monitoring of piston engine’s crankshaft torsional vibrations by measurement of Instantaneous Angular Speed at free and power output ends of the engine. It is assumed that calculation of differential value of angular distance run between both ends in the same time shall give the picture of torsion angle magnitudes and phases of the peak values. Fir carrying out such measurements, high frequency of sampling was required. The angular speed measurements is to be done utilising two optical sensors for reading and two perforated discs mounted at shaft’s ends playing the role of speed signal emitters. In the paper is presented description of the measurement system and explanation of its mode of work. It is also shown analysis of measurement accuracy, way errors elimination and method of signals runs filtration. Presented results of experiment derives from test cycle carried out using laboratory stand of Gdynia Maritime University equipped with 3- cylinder self - ignition engine, powering electric generator.

5

Impact of rise of exhaust resistance at torque and angular speed of two-stroke engine

Dereszewski M., Charchalis A.

Journal of KONES

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2015

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Vol. 22, No. 4

87--93

EN

It is assumed that elements of Exhaust Gases Cleaning Systems creates additional resistance along fumes duct and can affect energetic process of combustion. In the paper are presented results of researches aimed on detection and recognition of dumping effect in the exhaust pipeline using devices dedicated for engine’s torque and angular speed measurement. The experiment was carried out in test stand of Gdynia Maritime University; equipped with one-cylinder, low speed engine working in two-stroke mode. Effect of increasing of gas flow resistance was achieved by installation of shutters in cross-section of exhaust pipe. The shutters diminished active flow „window“ for 50% of normal crossection area of the exhaust pipe The plan of measurements encompasses registration of Instantaneous Angular Speed of the engine’s shaft and parallel registration of Instantaneous Value of Shaft Torsion, what reflect fluctuation of torque. Value of angular speed and toque enables exact calculation of power produced by the engine. Experiment included measurements at different levels of engine’s load and with changes of mean rotational speed. Angular speed and shaft’s torsion were measured and recorded using system ETNP-10 which is based on optical sensor and set of toothed discs. That method gives high accuracy of angular speed and torsion measurement. Results of experiment are presented as difference of related curves of values’ variations of angular speed and torsion occurring at the propulsion shaft connecting the engine and the water brake.

6

Validation of reference sampling for failure detection by crankshaft angular speed analysis

Dereszewski M., Charchalis A.

Journal of KONES

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2014

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Vol. 21, No. 3

67--74

EN

The paper presents results of the experiment focused on evaluation of records of runs of the engine in good condition as a reference for subsequent detection of faults of fuel system of medium speed diesel engine. The aim of research was determination of limits of instantaneous angular speed's spread spotted between random starts of the engine, without any fault condition simulation. Due to fine variation of the load setup and different ambient condition, every record of angular speed of independent starting, despite of attempts to sustain the same load and rotational speed value, presents some deviations between runs. Having on mind utilization of such measurement as a template for further comparison, is crucial to find out how random changes of ambient conditions and accuracy of revolutionary speed setup affect the IAS magnitude course. The answer was got in way of registration of numerous runs of the test engine after independent starts and hand adjustment of required RPM’s. The experiment was carried out at laboratory stand in Gdynia Maritime University, equipped with diesel engine Sulzer 3AL 25/30 driving electrogenerator. Sulzer 3AL 25/30 is three cylinder, medium speed, four stroke marine diesel engine, with maximum output 400 kW at 750 rpm. Independent records were treated as random variable and were compared each other. Obtained results were compared with differences between healthy engine and with simulated malfunctions of fuel injection.

7

Validation of reference sampling for failure detection by crankshaft angular speed analysis

Dereszewski M., Charchalis A.

Journal of KONES

|

2014

|

Vol. 21, No. 4

63--70

EN

The paper presents results of the experiment focused on evaluation of records of runs of the engine in good condition as a reference for subsequent detection of faults of fuel system of medium speed diesel engine. The aim of research was determination of limits of instantaneous angular speed's spread spotted between random starts of the engine, without any fault condition simulation. Due to fine variation of the load setup and different ambient condition, every record of angular speed of independent starting, despite of attempts to sustain the same load and rotational speed value, presents some deviations between runs. Having on mind utilization of such measurement as a template for further comparison, is crucial to find out how random changes of ambient conditions and accuracy of revolutionary speed setup affect the IAS magnitude course. The answer was got in way of registration of numerous runs of the test engine after independent starts and hand adjustment of required RPM’s. The experiment was carried out at laboratory stand in GdyniaMaritimeUniversity, equipped with diesel engine Sulzer 3AL 25/30 driving electrogenerator. Sulzer 3AL 25/30 is three cylinder, medium speed, four stroke marine diesel engine, with maximum output 400 kW at 750 rpm. Independent records were treated as random variable and were compared each other. Obtained results were compared with differences between healthy engine and with simulated malfunctions of fuel injection.

8

Wykorzystanie modelu dynamicznego silnika Sulzer 3AL 25/30 do symulacji wpływu zmian obciążenia i uszkodzeń na niestacjonarność prędkości kątowej

Dereszewski M.

Zeszyty Naukowe Akademii Morskiej w Gdyni

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2013

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nr 81

28--37

PL

W artykule przedstawiono wykorzystanie uproszczonego modelu matematycznego silnika Sulzer 3AL 25/30 napędzającego prądnicę prądu przemiennego, do przewidywania wpływu zmian obciążenia i prędkości obrotowej na zmiany wartości prędkości kątowej chwilowej wału korbowego. Uproszczony model dynamiczny silnika nie uwzględnia wpływu drgań skrętnych wału na wartość prędkości kątowej. Założono, że ze względu na dużą sztywność wału korbowego silnika trzycylindrowego wpływ drgań skrętnych można pominąć. W celu uzyskania przebiegów siły stycznej dla różnych obciążeń wykorzystano wartości ciśnienia pomierzone indykatorem elektronicznym. Badania wykonano na stanowisku silnika średnioobrotowego 3AL 25/30. Przeprowadzono symulacje pracy silnika bez obciążenia oraz przy obciążeniach N = 50 kW, 100 kW, 150 kW oraz 200 kW. Wyniki badań przedstawiono na wykresach porównawczych, które pozwalają na wnioskowanie diagnostyczne. Symulacje modelowe stanów uszkodzenia silnika pomagają przy ocenie i klasyfikacji przebiegów rzeczywistych niestacjonarności prędkości kątowej pomierzonych za pomocą enkodera fotooptycznego ETNP–10.

EN

The paper presents utilization of simplified mathematical model of engine Sulzer 3AL 25/30 for prediction of impact of failure, load and rotational speed changes at fluctuation of instantaneous angular speed of the crankshaft. Simplified model omit torsional vibrations impact at angular speed instantaneous value. It was assumed than due to stiffness of three – cylinder engine shaft, angular deviations due to torsional vibrations are not considered. In order to obtain the value of tangential force at different loads, real values of in – cylinder pressure, measured by electronic indicators, were taken. Experiment was carried out at Sulzer 3AL 25/30 test bed. During experiment, measurements at loads of idle run, 50 kW, 100 kW, 150 kW and 200 kW were conducted. Results were presented in form of comparison graphs, which let to build diagnostic conclusions. Simulations are useful for evaluation and classification of real runs of instantaneous angular speed, measured using optical encoder ETNP-10.

9

Zastosowanie sztucznej sieci neuronowej do regulacji prędkości kątowej silnika indukcyjnego w układzie sterowania typu IFOC

Krupa M., Flasza J.

Napędy i Sterowanie

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2013

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R. 15, nr 9

132--138

PL

W artykule dokonano porównania wybranych metod sterowania pracą maszyny prądu przemiennego, tj. metody IFOC oraz DTC-SVM, w aspekcie bezczujnikowej regulacji prędkości kątowej silnika indukcyjnego przy wykorzystaniu sztucznych sieci neuronowych. Celem niniejszej pracy jest ocena efektywności działania oraz zasadności stosowania sztucznych sieci neuronowych, przewidzianych do zadań (regulacyjnych) regulacji prędkości kątowej maszyny indukcyjnej w rozwiązaniach praktycznych. Szczególnie interesujące z punktu widzenia procesu regulacji dla przedstawionych metod sterowania są stabilność procesu, odporność na zakłócenia oraz zdolności adaptacyjne rozważanych struktur neuronowych.

EN

On the basis of the design for a new electric power system including wind-electric and solar power stations, coming into being at the Faculty of Electrical Engineering at Czestochowa University of Technology, the authors intend to present in some stages the possibility of using the existing renewable energy sources to the new opportunities for mini combined heat and power (CHP) plants. The resultant system will be responsible for data collection and analysis to focusing on cogeneration and implementation of the data in true applications.

10

Attempt of injectors failure detection based on measurement of the angular speed discrete value

Dereszewski M., Charchalis A.

Journal of KONES

|

2013

|

Vol. 20, No. 3

131--137

EN

The paper presents results of the experiment focused on detection of faulty injector of medium speed diesel engine, in way of analysis of IAS (Instantaneous Angular Speed) of the crankshaft. The experiment was carried out at laboratory stand in Gdynia Maritime University, equipped with diesel engine Sulzer 3AL 25/30 driving electrogenerator. Sulzer 3AL 25/30 is three cylinder, medium speed, four stroke marine diesel engine, with maximum output 400 kW at 750 rpm. In order to evaluate of IAS utility for diagnosis of the engine, two kinds of wrong adjustment of fuel injection valve’s spring were simulated. First malfunction was too weak spring (initial tension of 15.0 MPa against 25.0 MPa in normal condition), the second was too strong tension of the spring (35.0 MPa). The base of experiment was to angular speed recording, in three different conditions of the engine: healthy one and with two simulated malfunctions. Measurements were carried out at two different loads, respectively 150 kW and 250 kW. The IAS was measured and recorded by the measurement system ETNP-10, which mode of operation was based on perforated disc mounted at the shaft and photo-optic sensor counting laser impulses. Noise decomposition of measurement results was based on triple smoothing using Savitzky-Golay filter. IAS runs of faulty engine were compared with healthy engine measurement, in order to detect all deviation from normal condition.

11

Evaluation of diagnostic information about marine engine work based on mesurement of the angular speed discrete value

Dereszewski M., Charchalis A., Polanowski S.

Journal of KONES

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2012

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Vol. 19, No. 2

121-128

EN

The paper presents results of the experiment, aimed on finding the answer whether IAS (Instantaneous Angular Speed) and angular acceleration of the crankshaft is carrying information about quality of combustion in cylinder of the diesel engine. The experiment was carried out at laboratory stand in Gdynia Maritime University, equipped with diesel engine Sulzer 3AL 25/30 driving electro-generator. Sulzer 3AL 25/30 is three cylinder, medium speed, four stroke marine diesel engine, with maximum output 408 kW at 750 rpm. In order to evaluate of IAS utility for diagnosis of the engine, two kinds of malfunctions of engine's fuel system were simulated. First malfunction was fuel leakage from high-pressure line; the second was partly plugged injector's nozzle. Construction of high-pressure fuel pump enables to simulate fuel leakage. The level of leakage was controlled by simultaneous measurement of pressure in the high-pressure tube. For simulation of injector malfunction, the chocked one was installed in second cylinder. The engine was running at different loads, starting from around 25% up to 70% of nominal. The IAS was measured and recorded by the measurement system ETNP-10, which mode of operation was based on perforated disc mounted at the shaft and photo-optic sensor counting laser impulses. Results of all measurement were smoothed in order to eliminate a noise. Measurement results of fault condition were compared with healthy engine measurements and with results of in-cylinder pressure diagrams, in order to detect all deviation from normal condition.

12

Analysis of crankshaft’s angular velocity waveforms as a method of long term monitoring of engine performance quality

Dereszewski M.

Zeszyty Naukowe / Akademia Morska w Szczecinie

|

2011

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nr 28 (100) z. 1

14-18

EN

The paper presents an idea to utilize crankshaft’s angular speed variation and its derivative for monitoring of trouble of Diesel engine combustion quality. Measurement of instantaneous angular speed, recording and archive of values is easy to obtain using optical indicator and programmable logic controller. Advantage of this method is simple installation and constant signal. Collected data can be processed on board, basing on MS Excel formulas. Observation of changes of instantaneous speed and acceleration can not replace more accurate monitoring systems like Main Effective Pressure measurement or vibration monitoring, but is an excellent tool for early warning. When a signal about deteriorating of engine performance is obtain, more accurate diagnostic can be implemented. Expected final result will be elimination of engine’s cycle’s irregularity. Proposed method is at early stage of investigation and further steps to prove its utility and to develop concluding rules are to be conducted. In the paper are presented preliminary analysis of some bunches of data collected from two bulk carriers, operating in similar condition.

PL

W artykule przedstawiono ideę wykorzystania funkcji zmian prędkości kątowej wału korbowego oraz jej pochodnej do monitorowania zakłóceń równomierności pracy cylindrów. Pomiar prędkości chwilowej, zapis i archiwizacja wartości jest łatwe do uzyskania przy zastosowaniu głowicy fotooptycznej sprzężonej ze sterownikiem programowalnym. Zalety powyższej metody to łatwość instalacji systemu oraz uzyskiwanie bieżącego sygnału. Zebrane dane mogą być obrabiane na statku w oparciu o formuły zapisane w programie MS Excel. Obserwacja zmian chwilowej prędkości i przyspieszenia kątowego nie zastąpi typowych pomiarów, takich jak pomiar ciśnienia indykowanego lub monitoring drgań, jest jednak doskonałym narzędziem do wczesnego informowania i ostrzegania. W przypadku otrzymania sygnału o pogarszającym się stanie jakości pracy silnika można przystąpić do dokładnego ustalenia przyczyn przy pomocy dokładnych metod pomiarowych. Oczekiwanym efektem finalnym tych działań powinno być usunięcie przyczyn nieregularnej pracy silnika. Przedstawiona metoda jest na wczesnym etapie badań i wymaga dalszych analiz w celu wykazania jej użyteczności diagnostycznej. W artykule przedstawiono wstępne analizy pakietów danych pochodzących z dwóch masowców operujących w podobnych warunkach.

13

Numeryczne modelowanie dynamiki podnoszonego ładunku

Gąska D., Margielewicz J.

Transport Przemysłowy i Maszyny Robocze

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2008

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Nr 1

57--60

PL

Współcześnie projektowane suwnice pomostowe charakteryzują się prostą oraz modułową konstrukcją [5], w wyniku czego wszelkiego rodzaju naprawy i remonty mogą być przeprowadzane sprawniej i efektywniej. Rozwój elektroniki, w szczególności układów automatycznej regulacji, umożliwił bezstopniową regulację prędkości kątowych silników elektrycznych, stosowanych w układach napędowych maszyn roboczych. Działające mechanizmy wykonawcze, przenoszące moc użyteczną, wytrącają suwnicę pomostową z położenia równowagi. Podatność ustroju nośnego maszyny powoduje, że wzbudzane obciążenia dynamiczne przyjmują najczęściej charakter drgań mechanicznych.