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1

Spalanie i rozkład termiczny żywicy epoksydowej z melaminą

Mizera Kamila, Sałasińska Kamila, Kozikowski Paweł, Borucka Monika, Przybysz Jan, Gajek Agnieszka

Przemysł Chemiczny

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2024

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T. 103, nr 4

534--540

PL

Spalanie i rozkład termiczny żywicy epoksydowej (EP) i żywicy epoksydowej z melaminą (EP/ME) zbadano za pomocą kalorymetru stożkowego i analizy termograwimetrycznej sprzężonej ze spektroskopią w podczerwieni z transformacją Fouriera (STA/FT-IR). Badanie wykazało, że zastosowanie melaminy w EP, jako środka ograniczającego palność, prowadziło do powstania warstwy zwęglonej na powierzchni spalanej próbki. W konsekwencji tego zmniejszała się maksymalna szybkość wydzielania ciepła oraz całkowita ilość wydzielanych dymów. Podczas analizy STA/FT-IR obserwowano wydzielanie się mniejszej ilości tlenku węgla dla EP/ME.

EN

The combustion and thermal decompn. of epoxy resin (EP) and epoxy resin with melamine (EP/ME) was studied using a cone calorimeter and thermogravimetric anal. coupled to FTIR (STA/FT-IR). The use of melamine in EP as a flame retardant resulted in the formation of a charred layer on the surface of the burned sample, which reduced the max. heat release rate and the total amt. of emitted fumes. During STA/FTIR anal., a lower amt. of CO release was observed for EP/ME.

2

Regression analysis of experimental data in a study of the performance of a flat flame burner

Petrov Ivan Antonov

Polityka Energetyczna

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2024

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T. 27, z. 2

89--104

EN

The complex nature of the combustion process, which simultaneously obeys the laws of thermodynamics, heat transfer, aerodynamics and the chemical kinetics of oxidation reactions, makes numerical modelling very difficult and the experimental approach is currently playing a crucial role in their investigation. The modern highly developed theory of experimental design combines various analytical procedures that allow, with a minimum number of experiments, the obtaining of maximum information about the physical or technological processes under investigation, the properties of materials and phenomena. The ability to determine the influence of the main mode and design parameters on the geometrical characteristics of the flare is a prerequisite for effectively influencing the combustion process in order to intensify it. The present work is an introduction to the methods of planning and knowledge of multifactorial experiments, including: the preparation, conduct and processing of experimental results; mastering the methodology of experimental research; using the methods of mathematical statistics and regression analysis to plan experiments; developing the ability to analyze the object of study; correctly selecting the optimization parameter and the essential factors of the object of study; building an experiment planning matrix to obtain an adequate mathematical model of the object. The objective of this work is to propose an approach to study the effect of mode and design parameters, on the basic dimensions and shape of the gas flare, based on regression analysis of experimental data in the study of the performance of a flat flame burner.

PL

Złożony charakter procesu spalania, który jednocześnie podlega prawom termodynamiki, wymiany ciepła, aerodynamiki i kinetyce chemicznej reakcji utleniania, sprawia, że modelowanie numeryczne jest bardzo trudne, a podejście eksperymentalne odgrywa obecnie kluczową rolę w ich badaniach. Nowoczesna, wysoko rozwinięta teoria projektowania eksperymentów łączy w sobie różne procedury analityczne, które pozwalają przy minimalnej liczbie eksperymentów uzyskać maksimum informacji o badanych procesach fizycznych lub technologicznych, właściwościach materiałów i zjawiskach. Umiejętność określenia wpływu trybu głównego i parametrów konstrukcyjnych na charakterystykę geometryczną płomienia jest warunkiem skutecznego oddziaływania na proces spalania w celu jego intensyfikacji. Niniejszy artykuł stanowi wprowadzenie do metod planowania i wiedzy o eksperymentach wieloczynnikowych, obejmujące: przygotowanie, prowadzenie i przetwarzanie wyników eksperymentów; opanowanie metodyki badań eksperymentalnych; wykorzystanie metod statystyki matematycznej i analizy regresji do planowania eksperymentów; rozwijanie umiejętności analizy przedmiotu studiów; prawidłowy dobór parametru optymalizacyjnego i istotnych czynników przedmiotu badań; zbudowanie macierzy planowania eksperymentu w celu uzyskania odpowiedniego modelu matematycznego obiektu. Celem artykułu jest zaproponowanie podejścia do badania wpływu trybu i parametrów projektowych na podstawowe wymiary i kształt pochodni gazowej, w oparciu o analizę regresji danych eksperymentalnych w badaniu wydajności palnika z płaskim płomieniem.

3

Perspektywy wykorzystania biomasy stałej i RDF w ciepłownictwie

Rajczyk Rafał

Instal

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2024

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nr 2

20--27

PL

W artykule analizowano możliwości zastosowania trzech wybranych paliw w ciepłownictwie. Biomasę stałą reprezentowały pelet ze słomy agro oraz PKS (palm kernel shell), badaniom poddano również paliwo alternatywne - RDF. We wprowadzeniu omówiono ogólnie wykorzystanie biomasy i paliw alternatywnych do wytwarzania ciepła, przedstawiono też sytuację rynkową ze szczególnym uwzględnieniem ilości biomasy wykorzystywanej obecnie w Polsce oraz międzynarodowej wymiany handlowej. Dla paliwa importowanego - PKS omówiono procesy transportu i ich wpływ na uzyskiwane efekty ekologiczne. W dalszej części pracy analizowano własności fizyko-chemiczne badanych paliw oraz ich popiołów. Przedstawiono skład chemiczny, charakterystyczne temperatury popiołu oraz wyznaczono wybrane wskaźniki eksploatacyjne, do których przydatności w prognozowaniu problemów eksploatacyjnych odniesiono się w dalszej części pracy. Paliwa spalane były w technologii fluidalnej, która po technologii rusztowej jest drugą z kolei powszechnie wykorzystywaną w ciepłownictwie, a jedną z jej najważniejszych zalet jest elastyczność paliwowa. Wykonano badania emisyjno-eksploatacyjne na stanowisku laboratoryjnym z warstwą fluidalną. Określono zawartości poszczególnych składników gazów spalinowych, dokonano również analizy procesów aglomeracji materiału warstwy i popiołu dennego. Przeprowadzone badania wykazały, że oba paliwa oparte o biomasę stałą cechują się korzystnymi właściwościami i są predysponowane do wykorzystania w ciepłownictwie. Z kolei przy spalaniu RDF należy zwrócić uwagę na możliwość powstawania problemów eksploatacyjnych, związanych przede wszystkim ze znaczącą zawartością chloru.

EN

The article discusses the possibilities of using three selected fuels in district heating. Solid biomass was represented by agro straw pellets and PKS (palm kernel shell), and an alternative fuel - RDF - was tested as well. The introduction deals with the use of biomass and alternative fuels for heat generation in general, and presents the market situation with particular emphasis on the amount of biomass currently used in Poland and international trade. For the imported fuel - PKS, transport processes and their impact on the achieved ecological effects were discussed. The following section presents the physical and chemical properties of the tested fuels and their ashes. The chemical composition, characteristic temperatures of the ash were presented, and selected operational indices were determined, the usefulness of which in predicting operational problems is referred to later. The fuels were combusted in fluidized bed technology, which, after grate technology, is the second most commonly used in district heating, and one of its most important advantages is fuel flexibility. Emission and operational tests were performed on a laboratory rig with a fluidized bed. The contents of individual components of exhaust gases were determined, and the agglomeration processes of the bed material and bottom ash were analyzed. The conducted research showed that both fuels based on solid biomass have favourable properties and are suitable for use in heating. In turn, when burning RDF, attention should be paid to the possibility of operational problems, primarily related to the significant chlorine content.

4

Innovative method of biomass combustion in the binary fluidised bed

Leski Krystian, Berkowicz-Płatek Gabriela, Żukowski Witold, Szyman Jakub

Ecological Chemistry and Engineering. S

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2024

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Vol. 31, nr 3

353--363

EN

In this study, a binary fluidised bed made out of quartz sand and cenospheres for the biomass combustion process was created. Materials were fluidised with air to achieve a vertical density profile (from 0.5 g/cm³ to 1.1 g/cm³) resulting from grains segregation. The density profile was selected to ensure optimal control over the location of the combusted fuel particle. This involved positioning the process as close to the bottom sieve as possible. Fluidised bed combustion was carried out at temperatures of 600 °C, 700 °C, 820 °C and 870 °C using straw, willow and sawmill pellets as fuels. Qualitative and quantitative analysis of flue gases was performed using an FTIR spectrometer. Over 90 % carbon conversion from the biomass to carbon dioxide was achieved at 700 °C. At 820 °C and 870 °C, 100 % of biomass carbon left the reactor as CO2. The composition of organic compounds in the process products remained low, reaching a maximum of 3.0 % wt. at 600 °C. To gain further insights into the processes occurring in the immediate vicinity of biomass samples, a complementary TGA/FTIR analysis was conducted. This aimed to clarify the impact of the biomass particle decomposition stage in the fluidised bed combustion process. The proposed mechanism for biomass combustion in the binary fluidised bed contains the particle decomposition stage and the subsequent stage resulting from the coalescence of bubbles containing flammable components and bubbles containing oxidiser.

5

Waste plastic oil as an alternative fuel: A review

Amardeep, Kumar Rakesh, Kumar Naveen

Archives of Thermodynamics

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2024

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Vol. 45, no 1

87--97

EN

Today, with the high population density of the world, the energy demand is increasing continuously. Global dependency on fossil fuels is very strong and there is a compelling need to reduce our energy consumption in order to offset greenhouse gas emissions. Due to regularly increasing prices of fossil fuels alternative fuels are needed to fulfill the requirements of developing countries like India. Plastics in today's world have become crucial. They are excessively used in industry, as well as in households and other fields due to their lightweight, durability, and design flexibility. Plastic demand is growing day by day, which now poses a huge environmental threat. The current study summarizes the use of WPO (waste plastic oil) in the diesel engine and also concludes the combustion, performance, and emission parameters. After an exhaustive literature search, some interesting results have been found. The study reveals that when using WPO as an alternative source in a diesel engine, the combustion, performance, and emissions are similar to those using conventional diesel fuel. An enhanced BTE (brake thermal efficiency) and reduced emissions of unburned hydrocarbons (UBHC) and carbon monoxide (CO) are reported.

6

Experimental investigations of CI engine performance using ternary blends of n-butanol/biodiesel/diesel and n-octanol/biodiesel/diesel

Singh Ashish Kumar, Pali Harveer Singh, Khan Mohammad Mohsin

Archives of Thermodynamics

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2024

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Vol. 45, no 1

109--118

EN

This study explored the ternary blends of biodiesel-diesel-n-butanol and biodiesel-diesel-n-octanol on common rail direct injec-tion (CRDI) diesel engines. The compositions of fuels, which varied from 0% to 100%, were altered by up to 5%. On the basis of their properties, these blends were chosen, with various concentrations of alcohol at 5% and 10%, 5% diesel, and the remainder being biodiesel. Two ternary fuel blends of waste cooking oil biodiesel (90–85%), diesel (5%), and butanol (5–10%), namely BD90D5B5 and BD85D5B10, and subsequently, another two ternary similar blends of waste cooking oil biodiesel (90–85%), diesel (5%), and octanol (5–10%), namely BD90D5O5 and BD85D5O10, were used to conduct the experiments. The experiments were done with varying injection pressure from 17° to 29° crank angle (CA) before top dead centre (bTDC). The optimum con-dition for the blends is achieved at 26°CA bTDC for 80% loading. So, the engine trials were conducted on 26°CA bTDC to attain the results. The BD90D5O10 blend achieved the lowest brake specific fuel consumption (BSFC) reading of 0.308 kg/kWh while operating at full load. The maximum brake thermal efficiency (BTE) was 31.46% for BD90D5B5. The maximum heat release rate (HRR) achieved with BD85D5O5 fuel blend was 58.54 J/°CA. The quantity of carbon monoxide that BD85D5B10 created was the lowest (25.86 g/kWh). BD85D5B10 had a minimal unburned hydrocarbon emission of 0.157 g/kWh while operating at full load. Oxides of nitrogen (NOx) were emitted in the maximum quantity by BD85D5O10, which was equal to 6.01 g/kWh. This study establishes the viability of blends of biodiesel and alcohol as an alternative for petro-diesel in the future to meet the growing global energy demand.

7

Modeling and Performance Analysis of Hydrogen Powered Hybrid Bike

Gurunathan Manoj Kumar, Hynes N. Rajesh Jesudoss, Bartoszuk Marian, Sujana Angela J., Al-Khashman Omar

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 3

360--368

EN

One of the most straightforward and affordable ways to produce hydrogen is by alkaline water electrolysis. In order to split water molecules into hydrogen and oxygen, an electrolyser is often subjected to current levels of 1.23V. The electrodes in an electrolytic cell are the primary structural component. The cathode electrode type is the one where hydrogen is created via the reduction reaction between the two types of electrodes. LPG is combined with hydrogen at a 4:1 ratio to lower the combustion energy because hydrogen cannot be used directly in a traditional SI engine due to its higher energy production during combustion. With the aid of a vaporizer unit, the hydrogen and LPG are combined in the necessary ratio. Through the bypass line created on the input manifold before the carburettor, where air is also mixed with the hydrogen-LPG fuel with the A/F ratio of 17:1 (stoichiometric ratio) for complete combustion, the fuel mixture is transported to the engine's combustion chamber. Due to the usage of LPG and hydrogen, full combustion may occur as a result of the production of a blue flame during combustion. Better mixing of the fuel and air can be achieved since the fuel mixture is conveyed in va-por state instead of semi-liquid form as in a conventional SI engine. This approach of using mix fuel (LPG+H2) for con-ventional SI engines can lower nitrogen oxide and hydrocarbon values in the exhaust gas more effectively.

8

Impacts of Using Exhaust Gas Recirculation and Various Amount of Dimethyl Ether Premixed Ratios on Combustion and Emissions on a Dual-Fuel Compression Ignition Engine

Stepanenko Denys, Rudnicki Jacek, Kneba Zbigniew

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 2

196--213

EN

In the presented research, the authors dealt with the specific properties of the combustion process of dimethyl ether (DME) in a combustion car (Volkswagen Golf IV) engine AJM 1.9 TDI PDE made by Volkswagen factory. Dimethyl ether is an alternative fuel produced most often from natural gas, which can be used in compression ignition engines as a single fuel or co-burned with diesel oil. This work describes the impacts of using exhaust gas recirculation system and various diesel to DME substitution ratios from 0% to approximately 25% (on an energy basis), on the combustion process in a dual-fuel diesel engine. The engine has been modified so that DME fuel is introduced into the intake manifold just before the intake valves. The diesel fuel supply system, operation algorithms of the engine electronic control unit and other engine elements were left unchanged as it was built by the manufacturer

9

Wpływ temperatury na proces spalania paliw typu RDF w warstwie fluidalnej

Kaczyński Konrad, Pełka Piotr

Rynek Energii

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2023

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Nr 5

47--58

PL

Obecnie ze względu na narastające potrzeby energetyczne świata oraz świadomość zagrożeń związanych z emisją gazów cieplarnianych, wykorzystanie energii z odpadów staje się coraz bardziej pożądane. Fluidalna technologia spalania to czysta i wydajna technologia ze względu na doskonałe właściwości mieszania i wymiany ciepła. Pozwala ona na wykorzystanie paliw nie tylko takich jak węgiel, czy biomasa, ale również komunalne odpady stałe. Coraz powszechniejszą tendencją jest częściowe lub całkowite zastąpienie paliw kopalnych przez paliwa alternatywne m.in. biomasę i RDF/SRF. Wartość opałowa tych paliw jest wysoka, zbliżona do węgla brunatnego. Największym wyzwaniem w stosowaniu paliw alternatywnych jest ogromne zróżnicowanie właściwości chemicznych i fizycznych tych paliw. W pracy przedstawiono analizę procesu spalania wytworzonych z odpadów komunalnych peletów RDF w zmiennej temperaturze prowadzonego procesu spalania. Badania przeprowadzono na reaktorze laboratoryjnym z cyrkulacyjnym złożem fluidalnym. Badania Zostały przeprowadzone w trzech różnych temperaturach komory spalania: 850°C, 750°C i 650°C i w strumieniu materiału inertnego Gs=2,5kg/m2s i Gs=5kg/m2s modelującym warunki w rzeczywistym palenisku. Z badań wynika, że technologia fluidalna może być uważana za jedną z bardziej efektywnych metod unieszkodliwiania odpadów komunalnych przy jednoczesnym wykorzystaniu ich potencjału energetycznego. Mogą one być z powodzeniem wykorzystywane zarówno w procesie spalania oraz zgazowania, czy pirolizy.

EN

Nowadays, due to the growing energy needs of the world and awareness of the threats associated with greenhouse gas emissions, the use of energy from waste is becoming more and more desirable. Fluidized bed combustion technology is a clean and efﬁcient technology in view of its excellent mixing and heat transfer characteristics. It allows the use of fuels not only such as coal or biomass, but also municipal solid waste. The current trend is to partially or fully replace fossil fuels by alternative fuels such as biomass and Refuse Derived Fuel (RDF )/ Solid Recovered Fuels (SRF). The caloriﬁc value of these fuels is high, while also competitive in comparison with lignite. The biggest challenge in the use of alternative is that these fuels have different physical and chemical properties. The paper presents an analysis of the combustion process of RDF pellets produced from municipal waste at a variable temperature of the combustion process. Tests were carried out in a laboratory reactor with a circulating ﬂuidized bed. The research was carried out at three different temperatures of the combustion chamber: 850°C, 750°C and 650°C and in the stream of material Gs=2.5kg/mzs and Gs=5kg/mzs modeling the conditions in a real boiler. The study shows that ﬂuidized bed combustion can be considered to be one of the most efﬁcient methods of neutralizing municipal waste while using its energy potential. They can be successfully used both in the process of combustion and gasiﬁcation or pyrolysis

10

Development of a Solid, Low-Smoke Rocket Propellant : Smoke Generation Intensity Tests Using a Laser and Photodiode Setup

Woźniak Przemysław, Kindracki Jan, Wacko Krzysztof, Gołofit Tomasz, Chmielarek Michał, Cieślak Katarzyna, Kozłowska Sylwia, Maksimowski Paweł, Mężyk Łukasz, Kołodziej Maciej, Zdybał Dominik

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

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2023

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Vol. 14, Nr 3 (53)

41--58

EN

The work completed and discussed in this paper was to determine the level of smoke generation intensity in a selection of solid rocket propellants developed to minimise the level of generated smoke. This is an important issue for the application of the developed low-smoke propellant in, for example, the sustainer motor of a rocket missile. Reduced smoke generation levels can help to significantly reduce the feasibility of enemy detecting rocket munition launch sites. The authors of this paper developed a test stand that quantified the smoke generation intensity in rocket propellants. The test stand setup, based on the scatter of a laser beam by smoke, measured the smoke generation intensity, including during the operation of a rocket motor. A rocket micromotor was used along with a test chamber to measure the intensity of the smoke generated. It was located directly behind the motor exhaust and provided three laser- photodiode measurement channels. Tests of the smoke generated during the combustion of black powder and a standard mixture of HTPB and AP at a ratio of 20:80 provided reference baselines for the smoke generation intensity tests on the developed rocket propellants. The authors determined the smoke generation intensity of the propellants based on ADN, HTPB, and GAP with various additives. The results produced made it possible to compare the tested materials and select the most preferable materials as measured by their low smoke generation intensity.

PL

Przeprowadzone prace miały na celu określenie poziomu intensywności dymienia wybranych stałych, rakietowych materiałów pędnych, opracowanych przy założeniu minimalizacji generowanego przez nie dymu. Stanowi to istotne zagadnienie w kontekście zastosowania opracowanego materiału pędnego o zmniejszonym dymieniu, np. w silniku marszowym pocisku rakietowego. Ograniczenie wytwarzania dymu może znacząco zmniejszyć możliwości wykrycia miejsca startu środków bojowych przez przeciwnika. Autorzy artykułu opracowali stanowisko badawcze umożliwiające otrzymanie wskazań intensywności dymienia rakietowych materiałów pędnych. Przygotowany system, oparty na rozpraszaniu wiązki światła laserowego w dymie, umożliwia pomiar intensywności dymienia m.in. w warunkach pracy silnika rakietowego. Zastosowano mikrosilnik rakietowy wraz z komorą badawczą układu pomiaru dymienia, umieszczoną tuż za wylotem z mikrosilnika, wyposażoną w trzy tory pomiarowe laser- fotodioda. Pomiary generowanego dymu podczas spalania prochu czarnego oraz standardowej mieszaniny HTPB z AP w stosunku 20-80 stanowiły poziomy odniesienia do porównania intensywności dymienia opracowanych materiałów pędnych. Autorzy określili intensywność dymienia materiałów pędnych opartych na zastosowaniu ADN, HTPB lub GAP oraz różnych dodatków. Otrzymane rezultaty pozwalają na porównywanie przebadanych materiałów oraz wyselekcjonowanie najlepszych pod kątem niskiej intensywności dymienia.

11

Professor Piotr Wolański - cosmic authority, the pearl of Polish science

Koptoń-Ryniec Izabela

Polish Technical Review

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2023

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No. 4

23--29

EN

Prof. dr hab. Piotr Wolański (1942-2023) was one the most outstanding Polish scientists of the recent decades, a visionary who brought the enormous contribution to Polish sector of space science when outlining a series of perspective area of development and hypotheses: those ones concerning the origin of the Moon, or decay of dinosaurs. In his scientific activities, he undertook the subjects connected with the problems of combustion and the methods of diagnostics of combustion processes, explosions and engines, and the collisions with the celestial objects. Space drives, development of multi-use rockets and transfer the discussed knowledge to the students were translated into the defined implementations. The first Polish satellite PW-Sat was constructed under the guidance of the Professor at Warsaw University of Technology and the study direction “Aviation and Space Science” became the permanent specialization in the faculties of Polish technical universities.

12

Application of liquid hydrogen as a fuel for future passenger aircraft

Stężycki Paweł

Journal of KONBiN

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2023

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Vol. 53, iss. 1

157--175

EN

The paper briefly reviews a recent initiative on the application of hydrogen as a fuel for future commercial aircraft. Special attention is paid to the benefits of using liquid hydrogen (LH2) to power aircraft engines. A comparison of LH2 to other fuels is presented, as well as a comparison of LH2 hazard to hazard imposed by typical jet fuel. Major attention is focused on the combustion of hydrogen benefits in turbine engines with classic deflagrative combustion chamber and engines utilizing detonative combustion of the hydrogen-air mixture. Benefits and problems with the utilization of LH2 are discussed in this paper.

PL

W artykule dokonano przeglądu niedawnej inicjatywy dotyczącej zastosowania wodoru jako paliwa do przyszłych statków komercyjnych. Szczególną uwagę zwrócono na korzyści z zastosowania ciekłego wodoru (LH2) do zasilania silników lotniczych. Porównano LH2 z innymi paliwami oraz przedstawiono zagrożenia z zastosowania LH2 z zagrożeniami stosowania tradycyjnego silnika odrzutowego. Ponadto, skupiono się również na spalaniu wodoru w silnikach turbinowych z klasyczną deflagracyjną komorą spalania oraz silnikach z detonacyjną komorą spalania mieszanki wodorowo-powietrznej. W artykule omówiono także zalety i problem związane z wykorzystaniem LH2.

13

The Influence of Olive Oil Waste as a Biofuel on the Exhaust Gases of the Internal Combustion Engine

Al-Aseebee Munaf D. F., Naje Ahmed Samir

Journal of Ecological Engineering

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2023

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Vol. 24, nr 5

322--328

EN

Future options for addressing the depletion of fossil fuels and reducing pollution from internal combustion engines may include biofuel as an alternative fuel. This study aims to experimentally and statistically assess the effect of using diesel-biofuel blends on the emissions of a single-cylinder direct-injection engine. Using recycled olive oil, a chemical Tran’s esterification process was used to create biofuel. The experimental results were contrasted with those of a one-dimensional engine model for exhaust emissions and torque, which showed high agreement between test and numerical data. In order to comprehend the factors that affect the engine’s reaction to variations in fuel composition, the thermodynamic characteristics of the engine for various blends were also supplied. According to the investigation, a mixture with 20% of the volume fraction of oleic acid methyl ester olive-based biofuel and 80% of the volume fraction of pure diesel can be an effective fuel alternative for cleaner exhaust emissions while offering almost the same performance.

14

Preliminary tests of a Diesel engine powered by diesel and hydrogen

Longwic Rafał, Tatarynow Dawid, Kuszneruk Michał, Woźniak-Borawska Gracjana

Combustion Engines

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2023

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R. 62, nr 4

35--39

EN

This article discusses the possibilities of powering a commonly used diesel engine with renewable fuels. It analyses scientific studies that clearly indicate that the use of hydrogen is a potentially future-proof option due to its potential to reduce specific fuel consumption and improve performance and increase thermal efficiency. The research was carried out on a laboratory bench designed to test a diesel engine fueled by different fuels. A proprietary hydrogen injection system with dedicated control software was used. Hydrogen injection pressures of 0.15, 0.18, 0.20 MPa and hydrogen injector opening times of 2.5, 3.0, 3.5 ms, respectively, were set as control parameters. The rapidly varying engine operating parameters were recorded and the parameters calculated from them were analysed.

15

Combustion of LPG/DME gas mixtures in an SI engine with correction of the ignition advance angle

Kubica Grzegorz

Combustion Engines

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2023

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R. 62, nr 3

147--152

EN

The paper presents the results of tests on a SI engine fueled with an LPG/DME blends of various composition. A number of experimental studies and calculations using a mathematical model were carried out to examine the suitability of this fuel. These tests allowed for the analysis of the changes taking place in the combustion process and the assessment of the main operating parameters of the engine. The engine was powered by an LPG/DME fuel mixture with different proportions of components. The share of DME ranged from 0% to 30% of the fuel mass. The obtained results reflect the operation of the engine in the full load range and selected rotational speeds. Measurement series were made for different settings of the ignition advance angle. Based on the obtained results, a corrected map of the ignition advance angle was developed. The obtained results confirm the usefulness of using the LPG/DME mixture to power the SI engine.

16

Combustion comparative analysis of pyrolysis oil and diesel fuel under constant-volume conditions

Szwaja Magdalena, Szymanek Arkadiusz

Combustion Engines

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2023

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R. 62, nr 4

90--96

EN

The article discusses the research results on the combustion of pyrolysis oil derived from the pyrolysis of HDPE plastics after its distillation. The tests were carried out in a constant-volume combustion chamber in conditions similar to those in a compression-ignition engine with a compression ratio of 17.5:1. The phases of premixed and diffusion combustion and the ignition lag were determined. Then, diesel fuel combustion tests were performed under similar pressure-temperature conditions. Comparative analysis was used to draw conclusions as follows: the percentage fraction of heat released from the premixed combustion phase to total heat for pyrolysis oil was nearly 22%, whereas this parameter is 15% for diesel fuel, the maximum combustion rate for the premixed combustion phase for pyrolysis oil was approximately 27% higher than the premixed combustion rate for diesel fuel, the ignition lag for pyrolysis oil was slightly longer compared to that for diesel fuel. The presented parameters have a significant impact on both the development of combustion and the thermal efficiency of the internal combustion engine. Summing up, one can conclude, that pyrolysis oil can be applied as a substitute for diesel fuel both as a single fuel or blend component with it.

17

Thermal Decomposition of Ammonium Perchlorate Encapsulated with Copper(II)/Iron(III) Oxide Nanoparticles

Gržetić Jelena D., Mijatov Slavko, Fidanovski Bojana, Kovačević Tihomir, Pavlović Vladimir B., Brzić Saša, Bajić Danica

Central European Journal of Energetic Materials

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2023

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Vol. 20, no. 2

114-137

EN

Thermal decomposition of ammonium perchlorate (AP), as a high energy oxidizer in composite solid rocket propellants (CSRP), greatly affects the burning rate of the propellant. This paper summarizes the results of a study of the synergistic catalytic activity of nano-CuO/Fe₂O₃ nanoparticles on thermal decomposition of AP. AP micro-particles are efficiently encapsulated with 1 and 5 wt.% of nano-CuO and/or nano-Fe₂O₃ nanoparticles by the fast-crash solventantisolvent technique. The efficiency of the encapsulation method was confirmed using FT-IR spectroscopy. Morphological characterization, performed using SEM-EDS microscopy, showed that encapsulation provides recrystallization and deagglomeration of AP and uniform nano-catalyst distribution. The catalytic efficiency of nano-CuO/ nano-Fe₂O₃ nanoparticles on the thermal decomposition of AP was investigated using DSC, and an increase in released heat was observed from 1453 to 1628 J/g. The catalytic activities of performed nano-catalysts were proven by decreasing the HTD and merging with the low decomposition temperature peak. The highest catalytic effect was obtained after encapsulating with 5 wt.% of nano-CuO and nano-Fe₂O₃ combined in a 50/50 mass ratio due to multiple mechanisms of catalytic activity of nano-Fe₂O₃. The effect of AP encapsulation with nano-Fe₂O₃ on the burning rate of CSRP was investigated and the obtained results showed a favorable effect on the combustion rate law.

18

Technical and economic study of the energy transition from natural gas to green hydrogen in thermal power plants

Moulebe Laince Pierre, Touati Abdelwahed, Obar Akpoviroro Eric, Belbsir Oumayma, Rabbah Nabila

Acta Innovations

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2023

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no. 49

49--59

EN

This research article contributes to the challenge of global warming by presenting the approach of the use of green hydrogen to reduce greenhouse gases. It shows that CO2 emissions can be significantly reduced in thermal power plants by replacing natural gas with green hydrogen as a fuel. This work presents the techno-economic study of the energy transition of a 12 MW thermal power plant based on green hydrogen. The presented study is based on the energy consumption of Nigeria, 73% of which is covered by natural gas thermal power plants. The obtained results show that the cost of this transition is ca. 17 million dollars (USD) for a reduction of 114 tCO2 per plant with a return on investment between 4-5 years. In addition, through modeling and numerical simulation, this article shows that estimated return on investment can be shortened by using the thermal power resulting from the turbine, through industrial use.

19

Effect of Karanja biodiesel blends on the characteristics of diesel engine

Yadav Sandeep, Kumar Amit, Chaudhary Abhilasha

Zeszyty Naukowe. Transport / Politechnika Śląska

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2022

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z. 115

249--264

EN

Extensive research is being conducted to create and use a wide range of alternative fuels to accommodate the world's growing energy needs. The objective of this experimental investigation was to analyze the effects of Karanja biodiesel blends on the performance, combustion, and emission characteristics of a compression ignition (CI) engine vis-a-vis neat diesel. Important physical parameters of Karanja oil were examined experimentally after transesterification and determined to be within acceptable limits. BTE of Karanja biodiesel blends was about 3-8% lower than diesel. For Karanja biodiesel blends, BSFC was about 2-9% higher than diesel but exhaust gas temperature and volumetric efficiency were lower. Emissions characteristics such as nitrogen oxides, hydrocarbons, and carbon monoxide were also analyzed for various tested fuels. Karanja biodiesel blends resulted in lesser CO and HC formation. Nonetheless, NOx emissions were around 10% greater than diesel. Peak cylinder pressure, heat release rate, and maximum rate of pressure rise versus crank angle were among the combustion characteristics parameters considered in this study. Combustion analysis revealed that for Karanja biodiesel blends heat release rate and peak cylinder pressure were lower than for neat diesel. Findings indicate that Karanja biodiesel can be considered a viable diesel engine fuel.

20

Analysis of advanced technology for combustion of homogeneous fuel mixture

Puškár Michal, Lavčák Matúš, Šoltésová Marieta, Kopas Melichar

Zeszyty Naukowe. Transport / Politechnika Śląska

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2022

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z. 117

211--220

EN

The most serious problems to overcome for a successful operation of the HCCI engine are control of the combustion phase, limited operational range, cold start of engine and high noise level during engine operation. This study aims at describing the engine power output characteristics and emission characteristics of HCCI engines under different testing conditions and the various challenges associated with these engines. Furthermore, this study holds a potential guide for overcoming these challenges and improvement of the engine power output as well as the emission characteristics. Thus, it is possible to say, concerning the performed investigation work, that HCCI combustion can be applied in existing conventional engines after their modifications. The most significant result of the HCCI process application is the reduction of NOx emissions and soot emissions, keeping almost the same engine power output as the conventional combustion process.