Wyniki wyszukiwania - Biblioteka Nauki

1

Examination of the ammonia dose influence on nitric oxides transformations into combined oxide - platinum SCR catalyst

100%

Kamela W. , Kruczyński S.

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tom Vol. 19, No. 4

253-258

EN

This paper presents the test results obtained from the combined oxide-platinum catalytic reactor used in the NH3-SCR system. The first reactor block was extracted from the oxide catalyst used in trucks. As the second module of the reactor a block with platinum acting as a catalyst was used with 2.5g/dm3 platinum load. During the tests the ammonia concentrations in the engine exhaust gases at the inlet of the reactor system were set to 240, 320 and 400 ppm. The article contains the results of the physical and chemical active surface structure tests of both reactor blocks with their active surface chemical microanalysis and its topographic pictures performed and taken with the Scanning Electron Microscope. The results of the NOX and NO conversion and the content of NO2 in NOX are presented in this paper as the function of combined reactors system operating temperature with three different ammonia concentrations in the exhaust gases. Additionally, the results of the measured ammonia slip at the outlet of the combined reactor were presented. The obtained results have shown that the increase in ammonia dose at the inlet of the system increases the nitric oxides conversion with the minimum influence on the ammonia slip. By using the platinum based catalyst block it was possible to widen the whole reactor system effective operating temperature due to the high nitric oxides conversion efficiency of the platinum block achieved at low operating temperatures. A low ammonia slip at the outlet of the combined catalytic reactor was obtained by use of the platinum reactor block whose properties allow for the high ammonia conversion.

2

Estimation of the oxide catalyst volume and the cells quantity influence on CO, HC and NOx conversion in the AVL boost computing application

100%

Kruczyński S. , Kamela W. , Duniec K.

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tom Vol. 19, No. 4

347-353

EN

The article contains the results of the simulation tests of oxidizing catalytic reactor obtained by use of the AVL Boost simulation application. The chemical reactions and the reactions rates on which computations were based are specified in this paper. The simulations were related to the influence of the catalytic reactor volume and reactor’s cells quantity influence on the carbon oxide, hydrocarbons and nitric oxides conversion levels. The influence on the nitric oxides conversion was presented in this paper as the content of NO and NO2 in NOX. The simulated computations were performed separately for the variable reactor volume ranging from 1 to 2.2 dm3 with a step of 0.4 dm3 and for the variable reactor cells quantity ranging from 200 to 600 cells per square inch with a step of 100 cpsi. As the input data for the simulation computations the actual values of the toxic compounds concentrations in the exhaust gases at the outlet of the Diesel engine were used. The measurements of the toxic compounnds were made at the chosen engine steady state work points and are presented in this paper as a graph of the toxic gases concentrations in the form of the function of the engine torque. The simulation computaitons were performed for the same points and their results are also presented in the form of the function of the engine torque. The Results presented in this paper have shown that the increase in the CO, HC and NOX conversion in the case of the oxide catalyst can be obtained both by increasing the reactor volume and its cells quantity. It also have been observed that the increase in the reactor cells quantity and volume is not proportional as regards the toxic gases conversion increase and lowers in the case of higher values of the simulated reactor parameters.

3

Badania symulacyjne i eksperymentalne utleniającego reaktora katalitycznego systemu filtra cząstek stałych w programie AVL Boost

72%

Kruczyński S. , Kamela W. , Duniec K.

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tom Nr 15

76-83

PL

W pracy przedstawiono wyniki badań symulacyjnych i eksperymentalnych utleniającego reaktora katalitycznego stosowanego w systemie filtra cząstek stałych silnika o zapłonie samoczynnym GM MultiJet 1,3 w aspekcie oceny zgodności obliczeń symulacyjnych z wynikami eksperymentalnymi. W pracy przedstawiono wyniki badań symulacyjnych wykonanych przy użyciu programu obliczeniowego AVL Boost oraz wyniki badań eksperymentalnych prowadzonych na rzeczywistym silniku spalinowym o zapłonie samoczynnym. W artykule przedstawiono kinetykę reakcji chemicznych wykorzystywanych przez program symulacyjny do obliczeń poziomów konwersji CO, HC oraz udziału NO i NO2 w NOX. Jako dane wejściowe do obliczeń symulacyjnych wykorzystano rzeczywiste wartości stężeń związków toksycznych spalin silnika. Analiza przeprowadzona została dla wybranych punktów pracy silnika przy stałej prędkości obrotowej. Przedstawione w pracy wyniki wykazały, że algorytm obliczeniowy programu symulacyjnego pozwala uzyskać zbieżne z wynikami eksperymentalnymi poziomy konwersji CO i HC. Jednocześnie zaobserwowano pewną rozbieżności uzyskanych wyników udziałów NO i NO2 w NOX.

EN

Article contains results of simulations and experimental investigations of oxidizing catalytic reactor from diesel particle filter system used in 1,3 MultiJet GM Diesel engine. Investigations were done to compare conformity of simulations and experimental results. Simulations were done under program for simulation calculations AVL Boost and experimental result were taken from investigations carried on Diesel engine. Chemical reactions and reactions kinetics on which calculations of CO, HC conversion levels and NO and NO2 participation in NOX were based on are specified in this paper. As the input data for simulation calculations the actual values of toxic species concentrations in exhaust gases at the outlet of diesel engine were used. Measurements of toxic species were made in chosen engine steady state work points. Results presented in this paper have shown that calculations algorithm in AVL Boost program allows to achieve CO and HC conversion levels that are convergent with experimental results. Simultaneously some differences were observed in results of NO and NO2 participation in NOX.

4

Active method of three way catalyst monitoring by use of wideband combustion mixture composition sensor

72%

Kruczyński S. , Tomaszewski D. , Kamela

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tom Vol. 14, No. 4

225-232

EN

In this paper the active method of three way catalyst monitoring by use of wideband combustion mixture composition sensor was described. This method relays on three way catalyst activity decrease by determination of it oxygen capacity decrease monitoring. Determination of catalyst oxygen capacity decrease was done by comparison of signals from wideband and binary combustion mixture composition sensors. These sensors were mounted before and after investigated catalyst. In this paper was described the test bench in which modified catalyst was used. The catalyst was modified to simulate it activity decrease. Paper contains the investigation procedure and also static and dynamic characteristics of wideband combustion mixture composition sensor. A hand of received results the characteristic of binary combustion mixture composition sensor reaction time on combustion mixture change in function of reactor activity was determinate. From received results the index of reactor oxygen capacity decrease was also determinate. Received results showed also that this method can be used for precise controlling of three way catalysts activity for on board diagnostic systems purposes. Additionally this method allows concluding on toxic gases emission in NEDC tests at steady state engine work cycle.