751 research outputs found

    Small Internal Combustion Engine Testing for a Hybrid-Electric Remotely-Piloted Aircraft

    Get PDF
    Efficient operation of a hybrid-electric propulsion system (HEPS) powering a small remotely-piloted aircraft (RPA) requires that a controller have accurate and detailed engine and electric motor performance data. Many small internal combustion engines (ICEs) currently used on various small RPA were designed for use by the recreational hobbyist radio-control (R/C) aircraft market. Often, the manufacturers of these engines do not make accurate and reliable detailed engine performance data available for their engines. A dynamometer testing stand was assembled to test various small ICEs. These engines were tested with automotive unleaded gasoline (the manufacturer\u27s recommended fuel) using the dynamometer setup. Torque, engine speed and fuel flow measurements were taken at varying load and throttle settings. Power and specific fuel consumption (SFC) data were calculated from these measurements. Engine performance maps were generated in which contours of SFC were mapped on a mean effective pressure (MEP) versus engine speed plot. These performance maps are to be utilized for performance testing of the controller and integrated HEPS in further research. Further follow-on research and development will be done to complete the goal of building a prototype hybrid-electric remotely piloted aircraft (HE-RPA) for flight testing. Minimum BSFC for the Honda GX35 engine was found to be 383.6 g/kW hr (0.6307 lbm/hp hr) at 4500 RPM and 60% throttle. The Honda GX35 was overall the better fit for incorporation into the HE-RPA

    Combined application of Artificial Neural Networks and life cycle assessment in lentil farming in Iran

    Get PDF
    AbstractIn this study, an Artificial Neural Network (ANN) was applied to model yield and environmental emissions from lentil cultivation in Esfahan province of Iran. Data was gathered from lentil farmers using face to face questionnaire method during 2014–2015 cropping season. Life cycle assessment (LCA) was applied to investigate the environmental impact categories associated with lentil production. Based on the results, total energy input, energy output to input ratio and energy productivity were determined to be 32,970.10MJha−1, 0.902 and 0.06kgMJ−1, respectively. The greatest amount of energy consumption was attributed to chemical fertilizer (42.76%). Environmental analysis indicated that the acidification potential was higher than other environmental impact categories in lentil production system. Also results showed that the production of agricultural machinery was the main hotspot in abiotic depletion, eutrophication, global warming, human toxicity, fresh water aquatic ecotoxicity, marine aquatic ecotoxicity and terrestrial ecotoxicity impact categories, while direct emissions associated with lentil cultivation was the main hotspot in acidification potential and photochemical oxidation potential. In addition, diesel fuel was the main hotspot only in ozone layer depletion. The ANN model with 9-10-6-11 structure was identified as the most appropriate network for predicting yield and related environmental impact categories of lentil cultivation. Overall, the results of sensitivity analysis revealed that farmyard manure had the greatest effect on the most of the environmental impacts, while machinery was the most affecting parameter on the yield of the crop

    PRZEWIDYWANIE EMISJI SADZY W PRZYPADKU PRZEJŚCIOWEJ PRACY SILNIKA W OPARCIU O DANE

    Get PDF
    Global vessel traffic is one of the origins responsible for air pollution. Annex VI of the IMO International Convention for the Prevention of Pollution from Ships (MARPOL) focusses on air pollution. Air pollution accrues mainly from energy conversion in combustion engines especially during transient engine operation. One significant pollutant is soot. It represents impure carbon substances in various sizes due to an incomplete combustion of hydrocarbons. This paper focusses on the data-based modelling of soot for transient engine operation in order to predict air pollution in the context of a sophisticated manoeuvring assistance system.  In a first step, a stationary approach is investigated and extended for transient engine operation. If one knows about the consequences of his actions, then the role of the human is enforced to decide on energy efficient and emission reduced ship operation, especially during ship manoeuvres.Globalny transport morski jest jedną z przyczyn zanieczyszczenia powietrza. Załącznik VI do Międzynarodowej konwencji o zapobieganiu zanieczyszczeniu morza przez statki (MARPOL), Międzynarodowej Organizacji Morskiej (IMO) odnosi się do zanieczyszczeń powietrza. Zanieczyszczenie powietrza jest głównie powodowane przez konwersję energii w silnikach spalinowych, w szczególności w przypadku przejściowej pracy silnika. Głównym zanieczyszczeniem jest sadza. Jest to zanieczyszczona substancja węglowa różnej wielkości, będąca wynikiem niepełnego spalania węglowodorów. Niniejszy dokument dotyczy modelowania emisji sadzy - głównego składnika cząstek spalin, w pracy silnika w warunkach przejściowych w oparciu o dane. W unikalnym systemie wspomagania manewrów, przewidywanie emisji spalin stanie się nowym elementem. Jeżeli nawigator zna konsekwencje swoich działań, to rola człowieka zostanie wzmocniona w odniesieniu do  podejmowania decyzji o energooszczędnym i ubogim w emisje spalin ruchu statków, w szczególności podczas manewrów. Dzięki modelowi matematycznemu,w pierwszej kolejności zostanie odwzorowany proces powstawania sadzy podczas stacjonarnej pracy silnika - przy stałych obrotach i obciążeniu. Następnie model ten zostanie tak rozszerzony, aby umożliwić symulację pracy silnika i powstawania sadzy w fazie przejściowej

    Liquefied Petroleum Gas (LPG) as a Fuel for Internal Combustion Engines

    Get PDF
    Liquefied hydrocarbon gases, containing mostly the mixture of C3-C4 hydrocarbons, in many countries serve as an important source of energy, also for internal combustion engines. On a world scale, at present, about 270 million tonnes of this fuel is produced, of which motorization consumes 26 million tonnes (~10%). Poland is one of these countries, where LPG is a popular engine fuel. Annual consumption of so called autogas is about 1.7 million tonnes with increasing tendency. Almost 3 millions of cars with bifuel engines, mostly spark ignition ones, are driven on Polish roads. An extensive logistical infrastructure accompanies the development of the use of this type of fuel in Poland. There are numerous production companies in Poland working to meet the needs of this branch of industry, as well as a modern service base. Intensive research and development works in this field are carried out. The exceptional advantages of LPG as an alternative engine fuel have been highly appreciated in Poland. These advantages result mainly from the simplicity of its production. Relatively low investment costs and energy consumption are needed to produce high-quality fuel by degasolining of natural gas or crude oil stabilization. LPG is produced as a byproduct in numerous petroleum refining processes and its quality is relatively close to the engine fuel requirements. The source of aliphatic hydrocarbons falling into LPG range can also be the processes of biomass conversion and in the near future, fermentation processes. Environmental advantages of LPG are primarily very low emission of almost all toxic components of engine exhaust gases compared to gasoline or diesel fuel. In this chapter the results of research works aimed at the improvementof exploitation properties, logistics and LPG combustion processes in spark ignitionengines are presented. In this area, anti-corrosion additives for LPG of very high effectiveness were obtained and tested. Also, with the help of additives, the problem of water separating from LPG during storage and transport in tankers has been solved. A multifunctional additive was obtained giving LPG adequate lubricity and detergent properties. The influence of water on the process of LPG combustion in a gasoline fuelled engine as well ways to supply water to the combustion zone are being studied. A mathematical model is being elaborated, precisely describing correlations between density and chemical composition of LPG as well as changes of density as a function of fuel temperature. In the realization of these plans LPG producing companies, research and development teams as well as producers of automobile LPG systems are involved. Successful completion of research works and design works will result in elimination of scarce disadvantages of LPG as an engine fuel, preserving at the same time all its numerous advantages as an alternative fuel for the future - the new era source of energy

    Predviđanje optimalne gustoće ekspandiranog polistirena za najbolje performanse toplinske izolacije polistirenske kompozitne iverice primjenom umjetne neuronske mreže

    Get PDF
    The objective of this study is to predict the optimum expanded polystyrene (EPS) densities for the best insulation properties of the particleboards manufactured with waste EPS instead of formaldehyde-based adhesives used in particleboard production with artificial neural network (ANN). For this purpose, the waste EPS particles of five different densities were used in the production of composite particleboards. The experimental dana used in the study were obtained from the previous study. Half of the beech, poplar, alder, pine and spruce chips were dried in a drying oven and the other half were naturally conditioned at room temperature, and then 18 mm thick three-layer composite particleboards were produced. The thermal conductivity of panels was determined according to ASTM C 518. The prediction model with the best performance and acceptable deviations was determined by using statistical and graphical comparisons between the experimental data and the prediction values obtained as a result of ANN analysis. Then, using this prediction model, the thermal conductivity coefficient values were estimated for the intermediate EPS densities that were not experimentally tested. According to the analysis findings, the thermal insulation performance for both beech and spruce polystyrene composite particleboards (PCP) panels increased with using of waste EPS foams with a density of 30 kg/m3. The lowest thermal conductivity values were obtained from the EPS waste foams with the density of 18, 13 and 22 kg/m3 for the PCP panels produced with poplar, alder and pine in the natural drying, respectively. In the technical drying, these values were found to be 15, 14 and 11-13 kg/m3, respectively. Technical drying showed much better thermal performance than natural drying while poplar indicated the best performance among the wood species.Cilj je ove studije primjenom umjetne neuronske mreže (ANN) predvidjeti optimalne gustoće ekspandiranog polistirena (EPS) radi postizanja najboljih izolacijskih svojstava iverice proizvedene s otpadnim EPS-om umjesto s ljepilom na bazi formaldehida, kakvo se rabi u proizvodnji iverice. Stoga je za proizvodnju iverice upotrijebljen otpadni EPS pet različitih gustoća. Eksperimentalni podatci primijenjeni u studiji dobiveni su prijašnjim istraživanjem. Jedna je polovica iverja bukovine, topolovine, johovine, borovine i smrekovine osušena u sušioniku, a druga je polovica iverja kondicionirana na sobnoj temperaturi. Od osušenoga i kondicioniranog iverja proizvedene su troslojne kompozitne iverice debljine 18 mm. Toplinska vodljivost ploča određena je metodom ASTM C 518. Predikcijski model najboljih svojstava i prihvatljivih devijacija određen je statističkom i grafičkom usporedbom eksperimentalnih podataka s vrijednostima predviđenima ANN analizom. Potom su primjenom predikcijskog modela procijenjeni koeficijenti toplinske vodljivosti za one gustoće ekspandiranog polistirena koje nisu eksperimentalno ispitane. Prema toj analizi, termoizolacijska svojstva polistirenske kompozitne iverice (PCP) od bukovine i smrekovine poboljšana su pjenom od otpadnog EPS-a gustoće 30 kg/m3. Najniže vrijednosti toplinske vodljivosti za polistirensku kompozitnu ivericu od prirodno osušene topolovine, johovine i borovine dobivene su uz uporabu pjene otpadnog ESP-a gustoće 18, 13 i 22 kg/m3. Za polistirensku kompozitnu ivericu od tehnički osušenog iverja te su vrijednosti bile 15, 14 i 11-13 kg/m3. Tehničkim sušenjem iverja postignuta su znatno bolja toplinska svojstva polistirenske kompozitne iverice nego prirodnim sušenjem, a topolovina je pokazala najbolja svojstva od svih ispitivanih vrsta drva

    Roadmap on semiconductor-cell biointerfaces.

    Get PDF
    This roadmap outlines the role semiconductor-based materials play in understanding the complex biophysical dynamics at multiple length scales, as well as the design and implementation of next-generation electronic, optoelectronic, and mechanical devices for biointerfaces. The roadmap emphasizes the advantages of semiconductor building blocks in interfacing, monitoring, and manipulating the activity of biological components, and discusses the possibility of using active semiconductor-cell interfaces for discovering new signaling processes in the biological world

    The doctoral research abstracts. Vol:6 2014 / Institute of Graduate Studies, UiTM

    Get PDF
    Congratulations to Institute of Graduate Studies on the continuous efforts to publish the 6th issue of the Doctoral Research Abstracts which ranged from the discipline of science and technology, business and administration to social science and humanities. This issue captures the novelty of research from 52 PhD doctorates receiving their scrolls in the UiTM’s 81st Convocation. This convocation is very significant especially for UiTM since we are celebrating the success of 52 PhD graduands – the highest number ever conferred at any one time. To the 52 doctorates, I would like it to be known that you have most certainly done UiTM proud by journeying through the scholastic path with its endless challenges and impediments, and by persevering right till the very end. This convocation should not be regarded as the end of your highest scholarly achievement and contribution to the body of knowledge but rather as the beginning of embarking into more innovative research from knowledge gained during this academic journey, for the community and country. As alumni of UiTM, we hold you dear to our hearts. The relationship that was once between a student and supervisor has now matured into comrades, forging and exploring together beyond the frontier of knowledge. We wish you all the best in your endeavour and may I offer my congratulations to all the graduands. ‘UiTM sentiasa dihati ku’ Tan Sri Dato’ Sri Prof Ir Dr Sahol Hamid Abu Bakar , FASc, PEng Vice Chancellor Universiti Teknologi MAR

    Review of experimental methods to determine spontaneous combustion susceptibility of coal – Indian context

    Get PDF
    This paper presents a critical review of the different techniques developed to investigate the susceptibility of coal to spontaneous combustion and fire. These methods may be sub-classified into the two following areas: (1) Basic coal characterisation studies (chemical constituents) and their influence on spontaneous combustion susceptibility. (2) Test methods to assess the susceptibility of a coal sample to spontaneous combustion. This is followed by a critical literature review that summarises previous research with special emphasis given to Indian coals

    Novel mathematical models for prediction of microbial growth kinetics and contaminant degradation in bioremediation process

    Get PDF
    Bioremediation is defined as a process, which involves decomposition of organic pollutant compounds available in soil and water resources into safe and eco-friendly materials, like water and CO2, by the microorganisms.  In the present article, mathematical modeling of the bioremediation process was conducted comprehensively, and new models proposed for the microbial growth kinetics and substrate consumption (contaminant degradation). Accordingly, six kinetic models were suggested for the biomass growth and six models for the substrate consumption. Moreover, two models were considered for specific growth rate constant of the microorganisms. Then, model predictions were compared to and validated by the available experimental data in the literature. According to the obtained results, the microbial growth kinetic model, entitled as “MVKH2”, the substrate (contaminant) consumption model, entitled as “MVKH2s”, and the Aiba specific growth rate constant model had the best performance and the least error value in predicting the bioremediation process. Results achieved from this study are a promising beginning for practical and experimental works
    corecore