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1

The study of the continuously rotating detonation combustion chamber supplied with different types of fuel

Łukasik B., Czyż S., Irzycki A., Rowiński A.

Journal of KONES

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2013

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Vol. 20, No. 3

259--266

EN

The paper summarizes research that was conducted last year as part of the project of “Turbine engine with detonation combustion chamber”. In this project, throughout 2012 and early 2013, tests were carried out on a test stand connected to the compressed air system. Research, of the rotating detonation phenomena, was carried out for a number of detonation chambers with different interior channel geometry. In addition, for each geometry configuration, tests were carried out for different levels of choking of the chamber outlet and hence for different pressures conditions inside the detonation chamber. This article presents the results of tests carried out for gaseous (hydrogen), hybrid (hydrogen + kerosene) and liquid (Jet-A) fuels, using different types of fuel injectors and for different fuel injection configuration settings (inside the chamber, or in front of the chamber). During these tests, parameters such as pressure behind the detonation wave (using piezoelectric sensors), the static pressure in front of and inside the detonation chamber and temperature: before, inside and at the outlet of the chamber, were measured. Research was performed for the various mass flow rates of air and fuel injected into the chamber that means for the different air-fuel equivalence ratios (Lambda). The main achievement of this study was to obtain a stable and reproducible rotating detonation of air and heated kerosene (Jet-A) mixture, thus the results presented in this paper presents mainly these tests as the most interesting to the reader

2

Some problems resulting from powering of turbine engines by liquified petroleum gas (LPG)

Balicki Wł., Kalina P., Snopkiewicz K., Irzycki A.

Journal of KONES

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2013

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Vol. 20, No. 4

17--22

EN

There has been observed for several years a number of attempts to introduce for everyday use small power units which utilize turbine engine as propulsion unit (the U.S., Japan, and Europe). Efficiency increase of such devices is achieved by improving of turbine engine design as well as utilizing of exhaust gas thermal energy to heat the compressed air supplied to combustion chamber and, for example to heat usable water. Significant orientation of turbine engine improvements lead to the modernization of combustion processes by applying of gaseous fuels (such as compressed natural gas) or implementation of high-temperature catalytic combustion. The purpose of these changes reduction of hydrocarbons, carbon monoxide and nitrogen oxides emissions. In Propulsion Department of Aviation Institute a scientific project has been realized, in which the object of study was aircraft turbine engine powered by a liquid propane-butane mixture. The paper presents some results of engine tests carried out, especially concerning feeding system, special fuel system applied LPG pumping systems with the use of sliding-vane pump and by means of pressure reservoir and combustion process of LPG atomized with the use of original GTD-350 vortex injector, adapted for aviation kerosene Jet-A.

3

Measurements of pressure in front of shock wave : assessment of methodology influence on the measurement results on the basis of experiments with the shock tube

Perkowski W., Irzycki A., Kawalec M., Łukasik B., Snopkiewicz K.

Journal of KONES

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2013

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Vol. 20, No. 4

333--340

EN

The experiments, described in the article, are related to research of a rotating detonation that has been conducted in the Institute of Aviation in Warsaw since 2009, under the OPIE project: “Turbine engine with detonation combustion chamber”. Measurements of the shock wave parameters, are among the most difficult in the art. This is due to high speed of the wave transition, and above all, a very small thickness of the shock wave. For the purposes of the mentioned project, a methodology for measuring pressure on the rotating detonation wave was developed. It included the type of sensors, their location and their protection from heat and flames. In order to determine the capabilities, limitations and accuracy of the method that was used, a series of experiments were planned and carried out. They enabled the assessment of the impact, on the measurement of pressure in the shock wave, of the following factors: the location of the sensor (frontal and lateral) relative to the shock wave front, protrusion or retraction of the sensor in its housing, the covering of the sensor with a protective layer (such as a high temperature silicon). This paper presents the results of the experiments that were carried out with use of a small shock tube of a simple design. The high-pressure part of the tube (so-called “driver”) was charged with the compressed nitrogen gas. The membrane was designed to be torn by pressure and pressure magnitude of the shock wave were measured by a “twin pair” of the Kistler 603B type piezoelectric sensors, one of which was always the reference sensor.

4

Initiation of rotating detonation in experimental combustion chamber : practical realization

Kawalec M., Perkowski W., Irzycki A., Snopkiewicz K., Wróblewski W., Bilar A., Łukasik B.

Journal of KONES

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2013

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Vol. 20, No. 4

163--168

EN

Since 2009 in the Institute of Aviation, Warsaw a project that aim is to develop combustion chamber with rotating detonation for turbine engine has been carried out. Desired fuel is aviation kerosene (Jet-A) detonated in air. One of the most important problems to be solved was the initiation of rotating detonation in combustible mixture, which requires the fulfilment of several conditions: 1) good mixing of combustible mixture components, 2) properly fast flow of combustible mixture in the cylinder-shaped channel, 3) the appropriate height of the flow channel, associated with detonation cell size for the combustible mixture, 4) use of a source of detonation initiation with an appropriate energy and power for a given combustible mixture. There were considered and tested, in practice several different types of initiators: a) spark electric discharge in air, b) plasma electric discharge (the so-called "exploding wire"), c) micro-explosive charges, d) blank ammunition, e) gas initiator (with detonation of acetylene-oxygen stoichiometric mixture induced by spark electric discharge). The paper summarizes the theoretical energy parameters of several types of initiators, and the results of their comparative research on the test bench. In the course of these researches, the pressures of the shock wave generated by the initiators and recorded by a fast pressure sensor located at a distance from the initiator were compared.

5

GTD-350 engine powered by LPG : research work

Kalina P., Niedziałek B., Gryglewski W., Irzycki A., Snopkiewicz K.

Journal of KONES

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2013

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Vol. 20, No. 3

209--214

EN

The paper presents results of comparative tests of exhaust gases toxicity of GTD-350 turboshaft engine powered by Liquefied Petroleum Gas (LPG) and conventional JET-A1 fuel. Structure of GTD-350 engine’s test bed was discussed. Because of explosion danger of LPG vapour the test stand was arranged in the open air. Paper comprises specification of LPG supply system, gas injector’s construction and visualization of LPG injection. The supply system was based on the newly constructed pressurized injectors. Required LPG operating pressure was obtained by pressurizing LPG tank using nitrogen and LPG-flow was controlled using needle valve. A series of photographs presents shape of fuel streams for new injector supplied by JET-A1 and LPG. Photos of flame torches for multi-hole and conical type injectors fuelled by LPG are inserted as well. A comparative study of carbon monoxide, nitrogen oxides, hydrocarbons and carbon dioxide as well as oxygen concentration for GTD-350 equipped with new injectors fuelled by LPG and standard supplied by Jet-A1 was carried out. The study comprised turbocharger speed range between 40 and 80% of NTS. The exhaust gas temperature comparison for above-mentioned configuration is presented as well. All data shown in presented figures are mean of 6 measurements. All completed tests were carried out for standard GTD-350 engine combustion chamber.

6

Testing of initiation of rotating detonation process in hydrogen - air mixtures

Balicki W., Irzycki A., Łukasik B., Snopkiewicz K.

Journal of KONES

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2012

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Vol. 19, No. 2

25-34

EN

The paper presents results of some research work done in the project, which aims to apply of an innovative combustion chamber to the turbine engine. Expected benefits of using of a new chamber in which classical deflagration type combustion process would be replaced with a detonation combustion type, arise from greater efficiency of FickettJacobs cycle, which corresponds to rotating detonation combustion, in comparison to "classical" Brayton cycle, characteristic of deflagration combustion. The presented task concerned fundamental research carried out on test bench designed and built at the Institute of Aviation in Warsaw. To initiate the detonation combustion in the fuel-air mixtures the ignition device of appropriately high energy is necessary. The released energy should be directed to the area where the mixture has proper constitution - preferably close to stoichiometric one. Four different ignition manners were examined in the course of research: electrical ignition system adapted from turbine engine (semiconductor spark plug), powder charge ignition (handgun cartridges), detonation primer ignition using pentryt, and high voltage discharge (plasma jet). The appearance of detonation type combustion was identified on the basis of combustion gas pressure run, measured using piezoelectric sensors at a frequency of 1 MHz.

7

Study of combustion chamber with a rotating detonation

Łukasik B., Rowiński A., Irzycki A., Snopkiewicz K.

Journal of KONES

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2012

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Vol. 19, No. 2

313-320

EN

Institute of Aviation in Warsaw realizes the project concerning the application of the phenomenon of combustion with rotating detonation to the combustion chamber designed and destined for turbine engines. The test chamber is adapted for supplying both with liquid (aviation kerosene) and gaseous fuels in the form of mixture with compressed air. It is equipped with a probe for pressure and temperature measurements inside the flame tube as well as at its inlet and outlet sections. The measuring system allows measurement of physical phenomenon at low (1 kHz) and high (1 MHz) frequencies. Electric signals representing temperature and pressure sensor's measuring quantities, fuel and compressed air supply systems parameters and ignition-triggering values are collected using data acquisition system controlled by a computer. The prototype of the combustion chamber was examined at the especially designed test facility to determine at quasi-static operating conditions its following characteristics: speed of inside shock wave, exhaust gas thermodynamic parameters and ignition and going-out limits of gaseous fuel. In this article construction of test bench, schematic diagrams of measurement and power supply systems as well as the research process, the way of measurement data analysis recorded during the carried-out experiments and data validation manner are detailed described. The method of measurement data processing, the resulting graphs, and the conclusions of the study are presented as well.

8

Procedures and treatments leading to reduction of toxic components emission in diesel engine's exhaust gas

Kalina P., Irzycki A., Snopkiewicz K.

Journal of KONES

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2012

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Vol. 19, No. 1

163-169

EN

The fight against global warming and Earth atmosphere pollution has been for years one of the most important tasks of governments and national economies of the European Union members. Abandonment of efforts leading to reduction mainly of carbon dioxide emission by heavy industry, electric power generation based on coal, passenger aviation and wheeled passenger transport will inevitably be leading to deterioration of health condition of our citizens. This article presents an overview of commonly used structural and technological treatments which have impact on reduction of toxic standardized exhaust pollutants in the surface transport, exemplified on SW 400 engine version of L2 / 3 and its turbocharged version 6CT 107 2/L2. The impact of: engine's adjustment parameters, catalytic afterburners, exhaust gas recirculation, modifications of injectors, turbochargers, supercharging air-cooling and particulates filter on carbon monoxide, hydrocarbons, nitrogen oxides and particulates emission was thoroughly examined. The parameters being compared were the results of toxicity tests according to ECE-R49 Regulation and a maximal smoke values on full-load characteristics. In conclusion, of the paper the limiting allowable values of toxic components emitted in Diesel engines exhaust gases in the following EU Emission Standards are presented.

9

High speed electromechanical energy storage

Rowiński A., Irzycki A., Snopkiewicz K.

Journal of KONES

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2012

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Vol. 19, No. 2

459-464

EN

Kinematical, electromechanical energy accumulator is a facility that converts supplied electrical energy to the kinetic one, stored in the rotating inertial system. Electric driving motors can operate both as a propulsion units, providing torque to the rotor shaft, and as generators in the course of braking. The prototype is designed to operate in a vacuum; the energy accumulator is located in a sealed pressurized vessel connected to the apparatus, which can generate vacuum pressure down to 1 Pa. The accumulator is destined for storage energy of 7.2 MJ at a speed of up to 20,000 1 / min. The energy accumulator is equipped with inert weight in the form of metal disc, connected to a composite band. In the course of operation, the rotor assembly is suspended in noncontact manner in housing assembly while the main body is fastened to the inner ring of the pressure vessel. The rotor consists of a shaft on which are mounted: a metal disc together with a band made of carbon fibre, inset into inert weight using epoxy resin; four disc rotors of two electric motors; two disks which are magnetic armature for electromagnetic bearings operating along the shaft axis; bushings of both sleeve bearings; fixing sleeves, washers and lock nuts to fix particular elements on the shaft. During normal operation the rotor is positioned in the radial direction through two electromagnetic bearings, top and bottom, located at both ends of shaft and operating in the differential arrangement, and in the axial direction - by a system of two eight-pole electromagnetic bearings. In the idle state rotor is based on the spherical tip of the mobile support and on the raceway of slide bearing located in the top cover. The prototype facility is designed to carry out performance tests, both under normal conditions of pressure and temperature and in vacuum environment, of: electromagnetic bearings, start-up/emergency devices, functional integration of all components and air tightness of tubing inside the tank. Measurement of radial and axial clearances between the rotor elements and housing for full speed range will be completed also.

10

Study on kerosene atomization process under a high speed air stream

Perkowski W., Irzycki A., Snopkiewicz K., Grudzień Ł., Kawalec M.

Journal of KONES

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2011

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Vol. 18, No. 4

341-347

EN

For the needs of fuel-injection system development for the experimental detonation combustion chamber with a rotating detonation (PoiG - Project: "Turbine engine with detonation combustion chamber") a series of experiments with injection of kerosene under a high speed air stream was performed at the Institute of Aviation. The proper preparation of combustible mixture is very important for the initiation and sustenance of a rotating detonation. The task in case of kerosene-air mixture is far more difficult than for mixtures of hydrogen-air or kerosene-oxygen. A simple stream injector has been tested as a base system, and the kerosene was injected perpendicular to the air stream vector directly from the plane wall of the constant cross-section channel. The process of injection and atomization of kerosene was observed in the special transparent visualization chamber, enabling the spray observation of two mutually perpendicular directions. In subsequent experiments air pressure, air temperature and air flow velocity as well as and injection pressure of kerosene were varied. The tested process was photographed and, in case of chosen experiments, filmed using a high-speed digital camera. The surveys were aimed at identifying and assessing of following parameters of fuel atomization process: the range of the fuel stream and filling grade of research channel with aerosol, aerosol homogeneity and the size of forming it droplets, the possible presence of fuel streams flowing down the walls of channel. The resulting photos allowed for more comprehensive, but only a qualitative assess of the spraying process, while the filmed small regions of visualization chamber allowed the counting down and dimensioning of droplets. This paper presents a test facility and measuring techniques applied during the research activity and selected results of carried out tests.

11

Investigation of blade piston compressor

Kalina P., Wodyński P., Irzycki A., Snopkiewicz K.

Journal of KONES

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2011

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Vol. 18, No. 3

143-148

EN

The paper presents the results of scientific research of the blade-type piston compressor which were conducted on the test rig built especially for this purpose. The construction concept of the compressor, design calculation of its main elements and tests of contact- and contactless sealing types were discussed in papers published at subsequent KONES-symposia 2009 and 2010. The results shown in present document are focused on studies of compressor having the piston equipped with labyrinth or contact seals. When testing on test bench, the intake air flow to the compressor as well as temperature and pressure of air compressed in the tank of 0.1 m3 were measured. Quick-changing pressure in the compression chamber and air temperature at the compressor's outlet were recorded and analyzed, also. The research was carried out for contact-type seals made of various materials which do not require lubrication and for contactless-type seals (labyrinth). In the course of studies the proper backlash between the piston and the cylinder wall was matched to ensure trouble-free operation of installation. The results of compressor power demand were presented in this article, too. This research work is performed under the framework program "Inicjatywa Technologiczna I" No 12218.

12

Impact of low-temperature corona discharges on gaseous pollutants level in diesel engine's exhaust gas

Irzycki A., Kalina P., Snopkiewicz K.

Journal of KONES

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2010

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Vol. 17, No. 2

145-152

EN

This publication presents the results of research on level changes of gaseous pollutants contained in the exhaust gas in the consequence of applying of equipment taking advantage of low-temperature corona discharges. Not only influence of different plasma reactor configurations on the emission of toxins have been evaluated, but also on the main parameters of the engine under test and exhaust gas cleaning efficiency as well. The device supplied by DC voltage of 10-15 kV the operating value generated a low-temperature corona discharge in the especially formed electrostatic field. The devices were located behind the exhaust manifold of Diesel engine then operated in the high temperature zone of exhaust. The survey was realized in parallel with on-going research program at Institute of Aviation which has related to purification of Diesel engine's exhaust gas from particulates. The test results of emission of toxins obtained using the flat-arrangement and the axial-symmetric reactor systems were compared and discussed. The multi-variant designs of axial-symmetric device allowed the purposeful formation of favourable shape and intensity of electrostatic field and values of current, which induced the corona discharge. This activity has created better research capabilities for different geometric configurations of the reactors, namely linear and angular location and size of deflecting electrodes, structure of blade assembly generating a corona discharge, matching of proper distance between deflecting electrodes and blades.

13

Comparison the piston air engine performance with aviation gasoline (Avgas) or the E-85 ecological fuel supply

Balicki W., Irzycki A., Snopkiewicz K.

Journal of KONES

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2010

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Vol. 17, No. 3

25-32

EN

The fuel presently used for feeding of aircraft piston engines (petrol including TEL) is characterized by "strong unfriendliness" for environment. Many research centres have been going on fuels investigation, which could substitute Avgas utilized in aviation. This is why are there no being in force for Europe standards defining the allowable emission of pollutions in exhaust gases of aircraft piston engines (equivalent to EURO - standards introduced for traction engines). The mixtures of gas o line and alcohols are tested as "alternative" aircraft fuels for spark ignition engines, and in case of Diesel engines - evenjet kerosene. During the research works on test bed carried out at Institute of Aviation the performance offour-stroke aircraft carburettor piston engine supplied by "classical" aircraft petrol and the E - 85 fuel (mixture of petrol and ethanol) were compared. Except for measuring the functional parameters of engine (rotational speed, torque, specific fuel consumption, pressures and temperatures) the emissions of gaseous pollutants incorporated in exhaust gas were measured and analyzed. The range of modifications of engine supply system - necessary to introduce in case of changing of fuel type within the tested engine -was worked up. There are foreseen comparative test of fuelling the engine with mixtures of petrol and alcohols in different proportions in the next phase of research works.

14

Blade-type piston compressor investigation of seals

Kalina P., Chomczyk W., Irzycki A., Snopkiewicz K.

Journal of KONES

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2010

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Vol. 17, No. 1

199-204

EN

The paper presents the test results of selected seals applied in the blade-type piston compressor designed and realized in Propulsion Department of Institute of Aviation according to Patent No 6822 specification. Principle of operation of the compressor and the construction of test stand utilized to the seals testing were presented in the paper published in the Journal of KONES 2009. The special blade-type piston realizes a pendulous movement in the circular cylinder divided into two bulkheads. Each of bulkheads, fitted out with a set of bidirectional operating valves, creates by sequential opening and closing of them two compression chambers for one blade. Comprehensive tests of different kinds of seals were carried out on a single-compression machine driven by pneumatic actuator. The pressure rise vs. blade movement and drop of pressure when the piston was stayed at top dead centre were measured. The results of leak tightness of other structures of blade-type piston were analyzed as well and are subject to the following paper. The new design of piston relied on fitting-out of piston with side disc was prepared with intention of eliminating the loss of usable pressure in compression chamber, especially in area of top dead centre. The proposed design eliminated the leaks on the drive shaft and lateral seals, but not on the cylindrical surface of disco.

15

Improvement of axially symmetrical plasma reactor structure within a framework of particles pollution decrease in engine's exhaust

Irzycki A., Kalina P., Snopkiewicz K.

Journal of KONES

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2009

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Vol. 16, No. 2

183-189

EN

Within a framework of researches on cleaning of Diesel engine's fumes of particulates the sequence of construction variants of axially symmetrical device was examined. The device was fitted with the plasma reactor, in which the particles gained the same electric charge as a result of passing through the corona discharge zone. Then they were tilted aside in electrostatic field and finally collected infilter module. The principal functional problem met during research works was that the soot gathering on insulators ofelectrodes caused the drop of voltage and fade-out the corona discharge. It was solved by introducing the air stream blowing away the soot layer as well as the back flow induced by pressure difference within stream of exhaust gas. The latest version of device was put the 8 - phase test of particles and gaseous pollutants on test bed equipped with two-way exhaust pipe. The applied arrangement made possible the testing of engine in cases: without purifier, when exhaust gas swam through inactive purifying device (without voltage), when exhaust gas swam through active plasma reactor (purifler supplied with voltage of 15 kV). Using the final version of device, the 66 % cleaning efficiency of exhaust gas from particles and 10% decreasing of gaseous pollutants volume was achieved. The developed device may be a good basis for working up of prototype version and subsequent operational research works, especially on turbo charged engines.

16

Blade piston compressor

Kalina P., Chomczyk W., Irzycki A., Snopkiewicz K.

Journal of KONES

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2009

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Vol. 16, No. 3

157-163

EN

The paper describes the principles of building and working of new blade piston compressor. dynamic force analysis of assembly of crankshaft and first research results are also presented. The working principle of this compressor was patented by prof. W. Chomczyk. The piston, in shape of a blade, executes a pendulum movement in a circular cylinder. The two bulkheads with valves create four compression chambers for one piston. The compressor features compactness of construction and high efficiency. The lack of side thrust of the piston on cylinder surface is a major advantage of the construction. The lack of friction between crown and cylinder makes it possible to build an oil-free compressor. The strength calculation of chosen elements was executed in MES (Cosmos WORKS program). The acceleration of piston was a parameter which was optimized. The investigation of different tightening was conducted on a single-compression machine. The single compression machine was driven by pneumatic actuator having the task of imitation of piston movement during the compression cycle. The results of investigations of labyrinth seals are described in the paper. The compressor can find use in truck and bus aggregate drives. Paper present analysis of crank and crosshead mechanism 's kinematics, and dynamic loads, strength analysis of compressor components and construction of compressor.

17

Researches of selected version axially symmetrical model plasma reactor to cleaning diesel exhaust gas of particulates

Zawadzki A., Irzycki A., Kalina P., Snopkiewicz K.

Journal of KONES

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2008

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Vol. 15, No. 2

563-569

EN

The investigations concerning application of plasma reactor to cleaning Diesel exhaust gas of particulates have been led at Institute of Aviation for several years. Crown discharges having positive potential generated in the reactor hand this positive charge over to solid particles contained in engine's fumes. Positively charged particles are subject to agglomeration and then acceleration in electrostatic field, which makes possible their catching in filter module. In present publication one of studied versions of device was described, in which the additional airflow against the high voltage electrode protecting insulator was applied to prevent the settling down of soot on them. The plasma reactor was powered by 15 kV - high voltage, which allow generating of fully developed corona discharge. The extensive investigations of value of corona discharge current were conducted depending on applied elements generating the discharge (the mesh of thin wires or linear blades) as well as on their configuration. It was found, that the best effects were achieved applying linear blades in form of two compact sets. The flow of fumes behind the reactor was divided in two zones - the internal one, leading the more pure part of fumes and the external one, containing the particulates deflected in electrostatic field, directed to filter module. The swirling vanes were placed on inlet of this module with the aim of producing the field of force of inertia, in which the heavier then fumes particles could be thrown away outside the channel limited with metal mesh and external side. The above mentioned elements form the space allowing the accumulation of caught particulates. Preliminary investigations showed over 60% effectiveness of cleaning of Diesel exhaust gas from solid particles and/or particulates.

PL

Od kilku lat w Instytucie Lotnictwa prowadzone są badania nad zastosowaniem reaktora plazmowego do oczyszczania spalin silnika o zapłonie samoczynnym z cząstek stałych. W reaktorze generowane są wyładowania koronowe o potencjale dodatnim, który przekazuje cząstkom stałym zawartym w spalinach jednoimienny ładunek. Dodatnio naładowane cząstki ulegają następnie aglomeracji i akceleracji w polu elektrostatycznym, co umożliwia ich wychwytywanie w module filtracyjnym. W niniejszej publikacji opisano jedną z badanych wersji urządzenia oczyszczającego, w którym zastosowano nadmuch dodatkowego powietrza zabezpieczający izolator wysokonapięciowej elektrody przed osadzaniem się na niej sadzy. Reaktor plazmowy pracował pod napięciem 15 kV enerując w pełni rozwinięte wyładowania koronowe. Przeprowadzono obszerne badania wartości prądu wyładowań koronowych w zależności od zastosowanych elementów generujących wyładowania (siatki cienkich drutów, bądź ostrzy liniowych) oraz od ich konfiguracji. Stwierdzono, iż najlepsze efekty można uzyskać stosując ostrza liniowe w postaci dwóch zwartych zestawów. Przepływ spalin za reaktorem rozdzielono na dwie strefy - wewnętrzną czyściejszych spalin oraz zewnętrzną spalin zawierających odchylone w polu elektrostatycznym cząstki stałe kierowane do modułu filtracji. Moduł ten wyposażono na wlocie w łopatki silnie zawirowujące spaliny w celu wytworzenia pola sił masowych odrzucających cięższe od spalin cząstki na zewnątrz kanału ograniczonego metalową siatką i ścianką zewnętrzną. Elementy te tworzyły przestrzeń umożliwiającą gromadzenie wychwyconych cząstek. Wstępne badania wykazały ponad 60% skuteczność oczyszczania spalin z cząstek stałych.

18

Researches of axially symmetrical model plasma reactor to cleaning diesel exhaust gas of particulates

Zawadzki A., Irzycki A., Kalina P., Snopkiewicz K.

Journal of KONES

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2007

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Vol. 14, No. 4

563-569

EN

The investigations were concentrated on axially symmetrical arrangements, which permit more convenient formation of electrostatic field and better practicability. The description of construction and results of preliminary investigations of axially symmetrical arrangement was presented in "Researches of model plasma reactor for purify Diesel exhaust gas of particulates" published in Journal of KONES 2006. In the publication the attention was drawn to the fundamental problems requiring the solution, and namely: - The quick coating of electrodes insulators with soot, which took effect of leakance of corona discharge current and fading away of discharge, - Somewhat low, over a dozen-percentage effectiveness of cleaning process in comparison with previously studied flat arrangement, which effectiveness came up to 40 %. Subsequent investigations were concentrated on capturing of above-mentioned difficulties. Some modified variants of device were prepared. The number of electrodes was limited from three to only one, which was enclosed with insulator serving as the cardinal bracket of blades assembly generating corona discharge and the deflecting electrode. This new arrangement permitted examination of several variants of device described in present publication, which in consequence constrained searching of methods of soot settlement limitation to two final solutions: blowing-in of air stream in place of soot settlement (described in present publication) as well as burning the soot sediment on artificially warmed surface of insulator (in preparation). In order to improve the cleaning effectiveness of the system, the empirical tests of different variants of discharge area formation are carrying out with simultaneously measurement of discharge current, being the measure of its intensity. The subjects of comparison were among other things the mesh of thin wires and the aggregate of linear blades. Applying of filter modules in form of concentric meshes of different diameter of net mesh caused the improvement of cleaning effectiveness to over 40 %.

PL

W badaniach skoncentrowano się na układach osiowo-symetrycznych, które pozwalają na dogodniejsze kształtowanie pola elektrostatycznego i stwarzają lepsze możliwości wykonawcze. Opis konstrukcji i wyniki wstępnych badań układu osiowo-symetrycznego opisano w publikacji zamieszczonej w "Journal of KONES 2006"[1]. W publikacji tej zwrócono uwagę na zasadnicze problemy wymagające rozwiązania, a mianowicie: - szybkie pokrywanie się izolatorów elektrod sadzą, co skutkowało upływnością prądu wyładowań koronowych i zanikiem tych wyładowań, - niską kilkunasto-procentową skuteczność oczyszczania urządzenia w porównaniu z uprzednio badanym układem płaskim, którym skuteczność ta wynosiła ok. 40 %. W dalszych badaniach skoncentrowano się na opanowaniu powyższych trudności. Wykonano zmodyfikowane warianty urządzenia, w którym ograniczono liczbę elektrod z trzech do jednej, otoczonej izolatorem, wykonanym jako główny wspornik zespołu ostrzy generujących wyładowania koronowe i elektrody odchylającej. Pozwoliło to na przebadanie kilku wariantów urządzenia opisanych w niniejszej publikacji, co w konsekwencji sprowadziło poszukiwania metod ograniczenia osadzania się sadzy do dwóch rozwiązań - z nadmuchem strumienia powietrza w miejsca osadzania się sadzy (opisanym w niniejszej publikacji) oraz z wypalaniem sadzy na sztucznie grzanej powierzchni izolatora (w przygotowaniu). W celu poprawy skuteczności oczyszczania, empirycznym badaniom poddawane są różne warianty kształtowania pola wyładowań koronowych, z pomiarem prądu tych wyładowań jako miary ich intensywności. Badaniom poddano m.in. warianty z siatką cienkich drutów w porównaniu z zespołem ostrzy liniowych. Po zastosowaniu modułu filtrów w postaci koncentrycznych siatek o różnej średnicy oczek uzyskano poprawę skuteczności oczyszczania do ponad 40 %.

19

Researches of model plazma reactor for purify diesel exhaust gas of particulates

Zawadzki A., Irzycki A., Kalina P., Snopkiewicz K.

Journal of KONES

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2006

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Vol. 13, No. 3

437-441

EN

The device being investigated generates the low-temperature corona discharge in the stream of exhaust gas, causing the positive charging of particulates. The charged particulates are coming in electrostatic field to agglomeration and acceleration and next mechanically separated from the fumes. The reactor is powered by 10 – 15 kV DC voltage. This work is a continuation of the previously reconnaissance research conducted in Institute of Aviation which showed, that principle problem to be resolved was the deposit of soot between high-voltage electrodes and their insolating housing which caused a current leakage and in effect gradual drop of supply voltage resulting the restriction of reactor’s effective work time. However the 40% effectiveness of exhaust gas purifying of particulates was the result, which encouraged the authors to continuation of research work. As opposed to earlier “flat” structure, the mentioned one is made as an axial symmetrical. The device is placed immediately behind the exhaust manifold and works in high temperature area. Several variants of basic reactor’s structures were investigated. Subsequent research work will comprise modifications of discharge zone and electrostatic field geometry as well improving efficiency of mechanical particulates separator.

PL

Badane urządzenie wytwarza w strumieniu spalin niskotemperaturowe wylądowania koronowe powodujące jedno-imienne dodatnie naładowanie cząstek starych. Obdarzone ładunkiem cząstki stale ulegają aglomeracji i akceleracji w polu elektrostatycznym, a następnie są mechanicznie oddzielane od strumienia spalin. Urządzenie jest zasilane prądem stałym o roboczym napięciu 10-15 kV. Prace stanowią kontynuację badań rozpoznawczych prowadzonych w Instytucie Lotnictwa, w wyniku których okazało się, że zasadniczym problemem do rozwiązania było osadzanie się sadzy między elektrodami wysokiego napięcia a ich izolacyjną obudową powodujące przepływ prądu, a w efekcie stopniowy spadek napięcia zasilania skutkujący ograniczeniem czasu efektywnej pracy urządzenia. Jednakże uzyskanie ok. 40% skuteczności oczyszczania spalin z cząstek stałych uznano za efekt zachęcający do dalszych badań. W odróżnieniu od uprzednio badanego modelu płaskiego obecne modelowe urządzenie wykonano w układzie osiowo-symetrycznym. Urządzenie usytuowane za kolektorem wylotowym silnika pracuje w strefie spalin o wysokiej temperaturze. Przebadano v kilku wariantach wyjściowe modelowe urządzenie będące podstawą dalszych modyfikacji, które obejmować będą zarówno kształtowanie strefy wyładowań koronowych i odchylającego pola elektrostatycznego, jak i doskonalenie mechanicznego separatora cząstek

20

An approach to active damping of diesel engine exhaust gas pressure pulsations by means of controlled injection of an air stream

Snopkiewicz K., Irzycki A., Wróblewski W., Cichocki A.

Journal of KONES

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2005

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Vol. 12, No. 3-4

273-280

EN

In this paper, the experimental method of active damping of piston engine exhaust gas pulsation is presented. The investigation was carried out on running 3-cylinder DI Diesel engine (Perkins AD3.152 UR Type 3250) on test bench fitted with specially designed exhaust piping. The damping method consists in an active control of flowing agent mass stream by means of injection of compressed air in synchronization to phenomenon in duct, i.e. in counter-phase to the pulsation to be compensated. The method is in assumption destined for damping of low-frequency pulsations in exhaust noise spectrum, whereas applying of classic resonance and absorptive silencers is less effective.

PL

W artykule opisano eksperymentalną metodę aktywnego tłumienia pulsacji spalin w układzie wydechowym silnika tłokowego. Badania prowadzono na 3-cylindrowym silniku wysokoprężnym Perkins AD3.152 UR typ 3250 na stoisku ze zmodernizowanym układem odprowadzania spalin. Metoda aktywnego tłumienia pulsacji polegała na kontrolowanym wtrysku sprężonego powietrza do strumienia spalin, zsynchronizowanym ze zjawiskami zachodzącymi w przewodzie wydechowym badanego silnika.