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Wyszukujesz frazę "exhaust valve" wg kryterium: Temat


Tytuł:
Behaviour of the exhaust valve cladding face under the service conditions
Autorzy:
Kończewicz, W.
Smoleńska, H.
Powiązania:
https://bibliotekanauki.pl/articles/244130.pdf
Data publikacji:
2009
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
exhaust valve
laser cladding
cobalt alloy
service wear
Opis:
During the ship engine operation one of the key problems is the exhaust valve durability. A special interest is in valve head face because this narrow part of the valve is responsible for tightness. Cobalt base laser cladding layer on the exhaust valve head face have been investigate under real service condition using the laboratory two-stroke diesel engine L22 for two years. During this time the engine was fuelling with both ordinary light fuel and biodiesel fuel. After removing from the valve head from the cylinder head the face surface were fully inspected optically. There were no damages and the surface was shining in the great deal however some dark "spots " on it. The samples made of the used valve head underwent microstructural investigation and hardness measurements. There were no observed substantial microstructural changes neither in the surface of the layer nor in the bulk of the clad. The decrease of the hardness numbers was observed but still clad layer presented higher hardness than steel base. This type ofclad layer underwent intensive laboratory examinations which contained oxidation experiments at different temperatures and corrosion in exhaust gases and with the present service experiment this method of valve head hard facing is suitable for practical applications.
Źródło:
Journal of KONES; 2009, 16, 1; 265-271
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on structures and properties of the laser cladding exhaust valve after service
Autorzy:
Kończewicz, W.
Krużycki, P.
Smoleńska, H.
Powiązania:
https://bibliotekanauki.pl/articles/244029.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
exhaust valve
laser cladding
cobalt alloy
service wear
Opis:
The cobalt base laser cladding layers which were built up on the exhaust valve head face of the heavy loaded marine diesel engine have been investigated. The valve head with cladded face were served successfully for 3000 hours in the engine of the Dar Młodzieży. After removing from the valve head from the cylinder head the face surface were fully inspected. The surface topography and roughness were evaluated. Microstructure on the cross section of the clad layer were analyzed using Scanning Electron Microscope (SEM) equipped with energy dispersive spectroscopy (EDS. Also microhardness of the clad layer was measured. The service conditions resulted with the formation of the scale which had different thickness and tended to cracking and spalling. The microstructure of the clad layers after service did not demonstrated serious degradation process. The decrease of the hardness numbers was observed but still clad layer presented higher hardness than steel base. This type of clad layer underwent intensive laboratory examinations which contained oxidation experiments at different temperatures and corrosion in exhaust gases, long time exposition in laboratory engine and in the end 3000 hours successfully service on the ship. After such experience laser cladding cobalt base layers may be recommended as a useful solutionfor both prolongs of the service life and a method of the regeneration of the slightly used valve heads is suitable for practical applications.
Źródło:
Journal of KONES; 2010, 17, 3; 211-216
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigating the effects of laser stellite pad welding on the service properties of valve steels
Autorzy:
Bogdanowicz, Z.
Grzelak, K.
Powiązania:
https://bibliotekanauki.pl/articles/246197.pdf
Data publikacji:
2009
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
internal combustion engine
exhaust valve
laser pad welding
surface layer
service proprieties
Opis:
In the work the results of tests on 50H21G9N4 and H9S2 valve steels with pad welded stellite layers are presented. Basic properties such as tribological and erosion resistance as well as high temperature oxidation resistance were determined. Testing conditions were accepted with certain simplification owing to the complexity oj mechanical and thermal load exhaust valves and, therefore, they do not reflect real operating conditions accurately. Specimens with and without laser, plasma and TIG pad welded stellite layers were subject to tests. The conducted tests showed the highest tribological resistance of stellite layers under the conditions of dry friction in comparison with the material in the initial state as well as plasma and TIG pad welded stellite layers. The main mechanism of the abrasive wear of the surface layer is an adhesive wear by breaking the connections and adhesions that are being formed. The research on wear by abrasive erosion showed a smaller decrease in the mass of specimens with pad welded stellite layers in comparison with plasma and TIG pad welded stellite layers as well as the material in the initial form without the pad welded stellite layer. The resistance of stellite layers to high temperature oxidation was showed in the research on heat resistance. Moreover, it was found that pad welding does not have any significant influence on the heat resistance of stellite layers.
Źródło:
Journal of KONES; 2009, 16, 1; 41-50
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Właściwości struktury oraz analiza porównawcza mikrotwardości przylgni zaworu wydechowego wzmacnianej stellitem oraz fazą międzymetaliczną Fe3Al
Properties of the structure and comparative analyis of microhardness of the exhaust valve face strengthened with stellite and Fe3Al intermetallic phase
Autorzy:
Garbala, Krzysztof
Cybulko, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/1845188.pdf
Data publikacji:
2020
Wydawca:
Centralny Ośrodek Badawczo-Rozwojowy Aparatury Badawczej i Dydaktycznej, COBRABiD
Tematy:
mikrotwardość
zawór wydechowy
stellit
faza międzymetaliczna
microhardness
exhaust valve
stellite
intermetallic phase
Opis:
W silnikach, w których stosuje się zasilanie sprężonym gazem ziemnym, LPG oraz innymi paliwami gazowymi, obserwuje się konieczność częstszej wymiany zaworów wydechowych. Zawory te w silnikach spalinowych mogą być eksploatowane przez krótszy czas niż ich odpowiedniki w silnikach zasilanych benzyną i olejem napędowym. Najbardziej narażona na degradację jest przylgnia zaworu wydechowego. Wynika to z temperatury spalania gazu ziemnego w komorze spalania oraz temperatury spalin mających kontakt z zaworem. W pracy przedstawiono porównawczy rozkład mikrotwardości w zaworach wydechowych napawanych fazą międzymetaliczną Fe3Al oraz stellitem.
In engines, fuelled with concentrated natural gas, LPG, and other gaseous fuels, the necessity for more frequent replacement of exhaust valves is observed. These valves in combustion engines may be operated for a shorter period than their equivalents in engines fuelled with petrol and diesel oil. The exhaust valve face is most exposed to degradation. This results from the combustion temperature of natural gas in the combustion chamber and the temperature of exhaust gas in contact with the valve. The paper presents a comparative distribution of microhardness in exhaust valves pad welded with Fe3Al intermetallic phase and stellite.
Źródło:
Aparatura Badawcza i Dydaktyczna; 2020, 25, 3; 151-164
2392-1765
Pojawia się w:
Aparatura Badawcza i Dydaktyczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Impact of Material Selection on Durability of Exhaust Valve Faces of a Ship Engine – A Case Study
Autorzy:
Smoleńska, Hanna
Kończewicz, Włodzimierz
Bazychowska, Sylwia
Powiązania:
https://bibliotekanauki.pl/articles/102904.pdf
Data publikacji:
2020
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
cobalt alloy
laser cladding
exhaust valve
stop kobaltu
napawanie laserowe
zawór wydechowy
Opis:
Two alloys were used in order to extend the service life of marine engine exhaust valve head. Layers of cobalt base alloys were made of the powders with chemical composition as follow: the layer marked L12; C-1.55%; Si-1.21%; Cr-29.7%; W-9%; Ni-2%; Mo<0.01%; Fe-1.7%; Co-54.83% and the layer marked N; C-1.45%; Co-38.9%; Cr24.13%; Ni-10.43%; W-8.75%; Fe-7.64%; Mo-7.56%; Si-2.59%. Base metal was valve steel after heat treatment. It was consisted of: C-0,374%; Cr-9,34%; Mn-0.402%; Ni-0.344%; Si-2.46%; Mo-0.822%; P-0.0162%; S-0.001%. Layers on the valve faces were produced by laser cladding using the HPDL ROFIN DL020 laser. Grinding treatment is a very popular form of regeneration of seat and valve plug adhesions. Properly performed grinding operation ensures dimensional and shape accuracy of the surface from 7 to 5 accuracy class and surface roughness Ra not less than 0.16 μm, depending on the object and method of grinding. The 75H and 150S types are a significantly simplified form of valve plug face grinders. Finishing treatment was carried out with a Chris-Marine AB75H sander on a sanding stand equipped with a compressed air system - the stand was designed by the author. The sander has been set up to the surface of the valve stem so that the grinding angle of the valve faces is 30°+10°. A flat grinding wheel T1CRA54–K was used for machining. The plunge feed was 0.01 mm/rev. The thickness of the welded layer after grinding was 1.2 mm. Both valves were installed in the ship’s engine and were used in real life. After 2000 hours of operation, the valve marked N was damaged. The valve marked L12 showed no damage and was in operation for the next 1000 hours.
Źródło:
Advances in Science and Technology. Research Journal; 2020, 14, 3; 165-174
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charge exchange control in a SI engine by early exhaust valve closing
Autorzy:
Żmudka, Z.
Postrzednik, S.
Przybyła, G.
Powiązania:
https://bibliotekanauki.pl/articles/248009.pdf
Data publikacji:
2013
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
spark-ignition engine
variable valve actuation
early exhaust valve closing
open theoretical cycle
charge exchange process
exhaust gas recirculation (EGR)
Opis:
The paper tackles the problems connected with the charge exchange in internal combustion engines. The theoretical analysis of the charge exchange process in the SI engine has been presented. A system with independent, early exhaust valve closing has been analysed. The analysed system enables realization of an internal EGR and elimination of a throttling valve from an inlet system and reduce the charge exchange work, especially within the range of partial load. The decrease of the charge exchange work leads to an increase of the internal and effective works, which results in an increase of the effective efficiency of the spark ignition engine. The open, theoretical cycle has been assumed as a model of processes proceeding in an engine. The system has been analysed individually and comparatively with open Seiliger-Sabathe cycle. Benefits resulting from application of the system with early exhaust valve closing have been assessed on the basis of the selected parameters: a fuel dose, a cycle work, a relative charge exchange work and a cycle efficiency. The best results within decrease of fuel consumption and increase of cycle efficiency are obtained for low engine load. The main parameters characterizing the process of the internal exhaust gas recirculation were also determined. These are the ratio and the multiplicity of the exhaust gas recirculation.
Źródło:
Journal of KONES; 2013, 20, 1; 387-394
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An experimental study of emission and combustion characteristics of marine diesel engine in case of cylinder Valves leakage
Autorzy:
Kowalski, J.
Powiązania:
https://bibliotekanauki.pl/articles/259195.pdf
Data publikacji:
2015
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine diesel engine
exhaust gas composition
emission
exhaust gas valve leakage
inlet valve leakage
Opis:
Presented paper shows the results of the laboratory tests on the relationship between throttling of both air intake duct and exhaust gas duct and a gaseous emission from the marine engine. The object of research is a laboratory, four-stroke, DI diesel engine, operated at loads from 50 kW to 250 kW at a constant speed equal to 750 rpm. During the laboratory tests over 50 parameters of the engine were measured with its technical condition recognized as a „working properly” and with simulated leakage of both air intake valve and exhaust gas valve on the second cylinder. The results of this laboratory research confirm that the leakage of cylinder valves causes no significant changes of the thermodynamic parameters of the engine. Simulated leakages through the inlet and exhaust valve caused a significant increase in fuel consumption of the engine. Valve leakages cause an increase of the exhaust gas temperature behind the cylinder with leakage and behind other cylinders. The exhaust gas temperature increase is relatively small and clearly visible only at low loads of the engine. The increase of the temperature and pressure of the charging air behind the intercooler were observed too. Charging air temperature is significantly higher during the engine operation with inlet valve leakage. The study results show significant increases of the CO, NOx and CO2 emission for all the mentioned malfunctions. The conclusion is that the results of measurements of the composition of the exhaust gas may contain valuable diagnostic information about the technical condition of the air intake duct and the exhaust gas duct of the marine engine.
Źródło:
Polish Maritime Research; 2015, 3; 90-98
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Difference spectrum as a measure of the state of wear of the exhaust valve
Widmo różnicowe jako miara stanu zużycia zaworu wylotowego
Autorzy:
Górnicka, D.
Powiązania:
https://bibliotekanauki.pl/articles/328575.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
combustion engine
exhaust valve
damage
failure diagnosis
vibroacoustic symptom
silnik spalinowy
zawór wylotowy
uszkodzenie
diagnostyka
symptom wibroakustyczny
Opis:
The article presents an algorithm of diagnosing damages to the exhaust valve of the combustion engine. The process of obtaining a symptom as a difference spectrum takes into account time selection, which allows to reduce significantly the calculations necessary to obtain a measure of malfunction. As a result, we obtain a simple measure not requiring special conditions of object work and insensitive to simultaneously occurring valve clearance which is inappropriately set. Thus, we obtain a measure easy to use in diagnostics in real time.
W artykule przedstawiono algorytm diagnozowania uszkodzeń zaworu wylotowego silnika spalinowego. Proces pozyskania symptomu w postaci widma różnicowego uwzględnia selekcję czasową, co pozwala znacznie ograniczyć obliczenia niezbędne do otrzymania miary niesprawności. W efekcie otrzymujemy miarę prostą, niewrażliwą na równolegle występujący nieprawidłowo ustawiony luz zaworowy i nie wymagającą specjalnych warunków pracy obiektu. Tym samym otrzymujemy miarę łatwą do wykorzystania w diagnostyce w czasie rzeczywistym.
Źródło:
Diagnostyka; 2016, 17, 4; 59-64
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Entropia dyskretnej transformaty falkowej i radialne sieci neuronowe jako narzędzia diagnostyki nieszczelności zaworu wylotowego w silniku ZS
Entropy of discrete wavelet transform and radial neural networks as a diagnosis tool of diesel engine exhaust valve fault
Autorzy:
Czech, P.
Powiązania:
https://bibliotekanauki.pl/articles/198343.pdf
Data publikacji:
2011
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
transformata falkowa
sieć neuronowa
diagnostyka
zawór wydechowy
silnik z zapłonem samoczynnym
wavelet transform
neural network
diagnostics
exhaust valve
compression-ignition engine
Opis:
W przypadku diagnozowania silnika spalinowego metodami drganiowymi nie można zapominać o występowaniu wielu źródeł drgań, co jest przyczyna wzajemnego zakłócania symptomów uszkodzeń. Ze względu na konieczność analizy sygnałów niestacjonarnych i impulsowych w niniejszym artykule wykorzystano dyskretna transformatę falkową (DWT). Na podstawie sygnałów zdekomponowanych za jej pomocą wyznaczono wartość entropii, która stanowiła podstawę do budowy wzorców stanów pracy silnika, przeznaczonych do uczenia sieci neuronowych. Z przeprowadzonych badań wynika, że istnieje możliwość wykorzystania radialnych sztucznych sieci neuronowych do oceny nieszczelności zaworu wylotowego w silniku ZS.
In case of diagnosing combustion engines by vibration methods, the presence of numerous sources of vibration cannot be neglected, which are the reason for reciprocal interference of symptoms of fault. Owing to the necessity of analyzing non-stationary and impulse signals, a discrete wavelet transform (DWT) has been applied in this study. Based on the signals' decomposition performed by means of the transform, the value of entropy was determined, which served as a basis in the construction of the states of engine operation intended for teaching neural networks. As results from the research, there is a possibility of using radial neural networks to assess the diesel engine exhaust valve fault.
Źródło:
Zeszyty Naukowe. Transport / Politechnika Śląska; 2011, 73; 15-20
0209-3324
2450-1549
Pojawia się w:
Zeszyty Naukowe. Transport / Politechnika Śląska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hardness prediction of a cold rolled Nimonic 80A exhaust valve spindle
Autorzy:
Kang, S. W.
Heo, S. J.
Yoo, J. H.
Kang, J. H.
Powiązania:
https://bibliotekanauki.pl/articles/367227.pdf
Data publikacji:
2019
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
Nimonic 80A
exhaust valve
stress-strain curve
hardness prediction
finite element method
zawór wylotowy
krzywa naprężenie-odkształcenie
metoda elementów skończonych
Opis:
Purpose: of this paper is to predict the hardness of cold rolled exhausts valve spindle fabricated of Nimonic 80A via axisymmetric finite element analysis, compression testing, and hardness inspection. Design/methodology/approach: The stress-strain relationship of Nimonic 80A was obtained via compression testing with deformation ratios of 10%, 20%, and 30%. Hardness changes caused by the strain hardening effect were measured in cut specimens in both the axial and circumferential directions following compression testing. The effective strain at the measurement position was calculated via finite element analysis. The regression equation for hardness changes caused by work hardening was derived from analysed strain and inspected hardness. The cold-rolling deformation of an exhaust valve spindle was analysed using axisymmetric finite element analysis. Findings: The stress-strain relationship calculated from compression testing was well expressed using the Holloman equation and the strain-hardness relationship by strain hardening was successfully regressed using the shifted power law model for Nimonic 80A, Nickel-Chromium based super alloy. Research limitations/implications: This research focused hardness prediction of spindle after ring rolling operation for generating beneficial compressive surface residual stresses for enhancing fatigue life. Further research to quantify compressive residual stress after rolling shall be followed to increase fatigue life. Practical implications: The cold rolling process is a typical incremental forming method and should be analysed under three-dimensional conditions. However, it takes lots of time to solve incremental forming analysis. To predict hardness distribution after rolling in the manufacturing field, FE analysis was performed under two-dimensional axisymmetric conditions based on the assumption of no friction generated by the rolling tool. The deformed shapes and hardness distribution from the inspection quality standard and two-dimensional FE analysis showed very similar results. Simplified finite element analysis method for ring rolling process for local area could be very effective method in the industrial field. Originality/value: The stress-strain relationship and the hardness and strain relationship were derived by compression test and hardness measurement for compressed specimen for Nimonic 80A, Nickel-Chromium based super alloy. And simplified finite element analysis method was suggested to predict deformed shape and hardness distribution of locally cold rolled region and achieved similar result between FE analysis result and Quality standard. Suggested method would be very effective method to engine spindle manufacture to predict hardness of different size of product.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2019, 94, 1-2; 13-21
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza efektywności niezależnego sterowania zaworami wylotowymi jako sposobu realizacji wewnętrznej recyrkulacji spalin
Analysis of effectiveness of independent exhaust valve control as a method of an internal EGR realization
Autorzy:
Żmudka, Z.
Postrzednik, S.
Przybyła, G.
Powiązania:
https://bibliotekanauki.pl/articles/132866.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Naukowe Silników Spalinowych
Tematy:
silnik spalinowy
otwarty obieg teoretyczny
wymiana ładunku
niezależne sterowanie zaworami wylotowymi
wewnętrzna recyrkulacja spalin
internal combustion engine
open theoretical cycle
charge exchange
independent exhaust valve control
internal exhaust gas recirculation
Opis:
Przeprowadzono analizę systemu z niezależnym, wcześniejszym zamknięciem zaworu wylotowego, który umożliwia realizację wewnętrznej recyrkulacji spalin oraz wyeliminowanie przepustnicy w silniku ZI. Odniesieniem dla oceny korzyści oraz badania efektywności pozyskiwania pracy, w wyniku zastosowania tego systemu sterowania, jest otwarty obieg teoretyczny Seiligera-Sabathe’a z powszechnie stosowaną klasyczną regulacją dławieniową obciążenia. Analizę porównawczą efektywności zastosowania zaproponowanego systemu przeprowadzono opierając się na wybranych wielkościach: dawce paliwa, pracy obiegu, względnej pracy wymiany ładunku oraz sprawności obiegu. Najlepsze efekty w zakresie zmniejszenia dawki paliwa i zwiększenia sprawności obiegu dla analizowanego systemu, w porównaniu do systemu z regulacją dławieniową, uzyskuje się w obszarze średniego obciążenia silnika.
A system with independent, early exhaust valve closing has been analysed. The analysed system enables realization of an internal EGR and elimination of a throttling valve from inlet system of a spark ignition engine. The open, theoretical cycle has been assumed as a model of processes proceeding in an engine. The system has been analysed individually and comparatively with open Seiliger-Sabathe cycle. Benefits resulting from application of the system with early exhaust valve closing have been assessed on the basis of the selected parameters: a fuel dose, a cycle work, a relative charge exchange work and a cycle efficiency. The best results within decrease of fuel consumption and increase of cycle efficiency are obtained for mean engine load.
Źródło:
Combustion Engines; 2013, 52, 3; 338-345
2300-9896
2658-1442
Pojawia się w:
Combustion Engines
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multiple symptomical analysis of fails in the EGR system of HDI engine
Autorzy:
Cieślikowski, Bogusław
Cygnar, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/133797.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Naukowe Silników Spalinowych
Tematy:
EGR
exhaust gas recirculation valve
fluorescence
IR
infrared spectroscopy
biocomponents
zawór recyrkulacji spalin
fluorescencja
spektroskopia w podczerwieni
biokomponent
Opis:
The article presents the process of fault location in the HDR-rhr engine EGR system based on the characteristics obtained in the conditions of traction measurements using the ESI Tronic 2.0 program. The measurements were obtained using the licensed BOSCH KTS540 diagnostic tester. In the process of diagnostic inference the PWM signal coefficient has been analyzed in relation to the level of boost pressure, mass variability and air temperature in the intake system (based on MAF data) and EGR valve positioning for variable angular positions of the accelerator pedal. Analysis of the characteristics allowed for proper identification of faults previously stored in the system with OBDII error codes. Attention was paid to the issue of sediment formation in the EGR valve channels as a result of using diesel oil with the participation of biocomponents. Sludge analysis was carried out in a certified laboratory using infrared spectroscopy methods. Conclusions have been drawn for the presence of non-oxidized components of organic origin precipitated in the channels of the EGR system.
Źródło:
Combustion Engines; 2019, 58, 4; 47-51
2300-9896
2658-1442
Pojawia się w:
Combustion Engines
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Diagnosing faults in the timing system of a passenger car spark ignition engine using the bayes classifier and entropy of vibration signals
Autorzy:
Czech, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/2203067.pdf
Data publikacji:
2022
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
internal combustion engines
diagnostics
Bayesian classifier
pattern recognition
spark-ignition internal combustion engine
exhaust valve of the internal combustion engine
silniki spalinowe
diagnostyka
klasyfikator bayesowski
rozpoznawanie wzorca
silnik spalinowy z zapłonem iskrowym
zawór wydechowy silnika spalinowego
Opis:
Today's systems for diagnosing the technical condition of machines, including vehicles, use very advanced methods of acquiring and processing input data. Presently, work is being conducted globally to solve related problems. At the moment, it is not yet possible to create a single procedure that would enable the construction of a properly functioning diagnostic system, regardless of the selected object to be diagnosed. Hence, there is a need to conduct further research into the possibility of using already developed methods, as well as their modification to other diagnostic cases. This article presents the results of research related to the use of the Bayes classifier for diagnosing the technical condition of passenger car engine components. Damage to the exhaust valve of a spark ignition engine was diagnosed. The source of information on the technical condition was vibration signals recorded at various measuring points and under different operating conditions of the car. To describe the nature of changes in the vibration signals, the entropy measures were determined for the decomposed signal using the discrete wavelet transform is proposed.
Źródło:
Zeszyty Naukowe. Transport / Politechnika Śląska; 2022, 116; 83--98
0209-3324
2450-1549
Pojawia się w:
Zeszyty Naukowe. Transport / Politechnika Śląska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modern diesel engines NOx particles emission
Autorzy:
Krakowian, K.
Kaźmierczak, A.
Wdowikowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/245526.pdf
Data publikacji:
2013
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
air pollution
combustion engines
EGR valve
exhaust emission & ecology
vehicles
Opis:
Exhaust gases recirculation systems (EGR), together with catalytic reactors, are commonly installed in modern piston combustion engines. Their purpose is to reduce the amount of nitrogen oxides (NOx) emitted in fumes. The need for this reduction takes its source from introducing more rigorous EURO standards, which are treating about maximum levels of NOx, HC and particulates produced, as a side effect of engine's operation. Applied exhausts recirculation circuits can be roughly characterized by a principle, that a part of exhaust gases is redirected (through a cooler) and reaches a special valve. This valve, respectively to engine's current load and speed, drives more or less exhaust to suction manifold. The position of the valve determines the system’s overall efficiency, but also differentiates the amount of toxic gases and smoke produced by each of the engines cylinders. Recent research have focused only on the overall efficiency of recirculation systems, representing it by measuring the total amount of NOx particles emission from exhaust pipe. However, the quantity of exhaust gases that is reaching each cylinder can be negatively dependant on EGR valve’s physical position in the circuit. This happens due to the fact that combusted loads have different proportions of charged air and fuel. For estimating the difference among each of the loads, and in the same time, indirectly, in equal emission of NOx from corresponding cylinders, a research was carried out on a model VW 2.0 TDI engine, equipped with standard, factory mounted, exhausts gases recirculation circuit. Measurements of toxic emissions were executed with regards to thirteen-point ESC (European Stationary Cycle) test.
Źródło:
Journal of KONES; 2013, 20, 3; 245-250
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adaptive control of exhaust gas recirculation at nonroad vehicle diesel engine
Autorzy:
Bieniek, A.
Graba, M.
Lechowicz, A.
Powiązania:
https://bibliotekanauki.pl/articles/247302.pdf
Data publikacji:
2011
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
exhaust gas recirculation (EGR)
NOx emissions reduction
adaptive control
EGR valve
Opis:
At diesel engines with fuel direct injection, the problems with toxic exhaust compounds concern mainly nitrogen oxides (NOx) and Particulate Matter (PM). For reduction of the NOx's, the exhaust gases are feedback to the combustion chamber. This results with a lower combustion temperature and decrease the emission of NOx gasses. The mass of the recirculated gases cannot be too high because it might lead to an increase in the PM emission. In nonroad vehicle engine the component responsible for the exhaust gases recirculation is most a two state (open/close) EGR Valve. Another problem in this type of combustion engines is volatility of its ecological parameters during exploitation. The reasons are various operation conditions of the engine, fuel quality ect. So, according to the proposed solutions, the engine controller must track these variations. The mass of recirculated gasses must also be corrected. In the proposed solution the EGR valve is a prototype construction of an electronically controlled EGR. The openness of the valve is freely programmable and is controlled by adaptive algorithm saved in the ECU (Electronic Control Unit). As feedback signal to control the openness of EGR valve is used an NOx sensor placed at engine outlet pipe. The paper describe an control circuit of EGR Valve and include research results of nonroad vehicle diesel emissions (NOx and PM missions). The proposed adaptive control of EGR Valve shows potential to reduce especially NOx emissions in aspect to fulfill further emission regulation TIER/Euro
Źródło:
Journal of KONES; 2011, 18, 4; 11-18
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł

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