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1

Effect of wood flour addition and modification of its surface on the properties of rotationally molded polypropylene composites

Barczewski M., Szostak M., Nowak D., Piasecki A.

Polimery

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2018

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T. 63, nr 11-12

772--784

EN

The aim of this study was to assess the effect of wood flour addition and the treatment of its surface on the properties and structure of rotationally molded (rotomolded) polypropylene. In this study, a random polypropylene copolymer (rPP) micropellet was rotationally molded with the direct addition of 5 wt % of commercial grade of wood flour Lignocel C120, untreated (WF) and chemically treated (mWF). Part of the natural filler was chemically modified by a silanization process using 3-aminopropyltriethoxysilane (3-APS). The structure, quality and mechanical properties of the polypropylene and composite rotomolded parts were discussed in terms of changes in the material’s thermal properties, evaluated by differential scanning calorimetry (DSC), thermomechanical properties, obtained by dynamic mechanical-thermal analysis (DMTA), and dynamic rheological properties, assessed by oscillatory rheometry. The structure of composites and fillers was analyzed by means of a scanning electron microscopy (SEM), while the analysis of the chemical structure of materials and final products was carried out by a Fourier transform infrared spectrometry (FT-IR). It was found that adding the natural filler, despite the application of a preliminary drying and chemical treatment caused creation of the pores and decreased the overall mechanical properties of the composites. The lower processing ability of the composites was ascribed to a higher complex viscosity and an increase in the elastic behavior of molten composite materials in comparison to pure rPP.

PL

Kompozyty polipropylenowe napełniane mączką drzewną otrzymywano metodą odlewania rotacyjnego. Rotowaniu poddawano kopolimer polipropylenowy (rPP) w postaci mikrogranulatu wraz z dodatkiem 5 % mas. niemodyfikowanej (WF) oraz modyfikowanej chemicznie (mWF) mączki drzewnej Lignocel C120, wprowadzonej razem z polipropylenem bezpośrednio do formy. Mączkę drzewną modyfikowano chemicznie w procesie silanizacji z zastosowaniem 3-aminopropylotrietoksysilanu (3-APS). Strukturę, jakość oraz właściwości mechaniczne odlewów polipropylenowych i kompozytowych omówiono w odniesieniu do zmodyfikowanych właściwości cieplnych ocenianych metodą różnicowej kalorymetrii skaningowej (DSC), właściwości termomechanicznych badanych za pomocą dynamiczo-mechanicznej analizy termicznej (DMTA) oraz właściwości reologicznych określanych techniką reometriirotacyjnej. Strukturę kompozytów oraz napełniaczy badano z zastosowaniem skaningowej mikroskopii elektronowej (SEM). Zmiany struktury chemicznej napełniaczy oraz odlewów oceniano na podstawie rejestrowanych widm spektroskopii w podczerwieni z transformatą Fouriera (FT-IR). Stwierdzono, że mimo wstępnego suszenia i modyfikacji chemicznej napełniaczy naturalnych, ich dodatek dopolipropylenu spowodował powstanie porowatej struktury w odlewach kompozytowych. Ograniczenie przetwarzalności kompozytów polipropylenowych napełnionych mączką drzewną przypisano zmianom ich właściwości reologicznych.

2

Analysis of water consumption in 2014-2017 in Toruń

Piasecki A., Górski Ł.

Infrastruktura i Ekologia Terenów Wiejskich

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2018

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nr IV/1

973--984

EN

This work analyses the variability of water consumption in Toruń over the years 2014-2017. The difference between the largest annual water consumption (2016) and the smallest (2014) was 13.2%. Higher consumption values typically occurred in the warm half-year, except in 2015. The lowest values occurred in the winter months (February), and the highest in the summer months (from June to August). The largest dayto-day variations in water abstraction were recorded at Easter and Christmas. There were differences between the average water consumption on particular days of the week, with the largest differences being between Saturdays (the highest value) and Sundays (the lowest value). Average unit water consumption was in the range of 58.2 to 67.3 dm3·M-1·d-1. On the basis of multiple regression analysis, a set of the factors with the greatest impact on the daily variability of water consumption in the city (in the warm half-year) was indicated. These factors include: evaporation, day of the week, humidity and maximum temperature.

3

Forecasting surface water-level fluctuations of a small glacial lake in Poland using a wavelet-based artificial intelligence method

Piasecki A., Jurasz J., Adamowski J. F.

Acta Geophysica

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2018

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Vol. 66, no. 5

1093--1107

EN

Lake waters are a significant source of drinking water and contribute to the local economy (e.g. enabling irrigation, offering opportunities for tourism, waterways for transport, and meeting utility water demands); therefore, the ability to accurately forecast lake water levels is important. However, given the significant lack of research with respect to forecasting water levels in small lakes (i.e. 0.05 km2\area\10 km2), the present study sought to address this knowledge gap by testing a pair of hypotheses: (1) it is possible to forecast water levels in small surface lakes using artificial neural networks (ANN), and (2) better water-level forecasts will be obtained when the wavelet transform (WT) is used as an input data preprocessing tool. Based on an analysis of a case study in Lake Biskupinskie (1.16 km2) in Poland and based on a range of model performance statistics (e.g. mean absolute error, root mean square error, mean squared error, coefficient of determination, mean absolute percentage error), both hypotheses were confirmed for monthly forecasting of lake water levels. ANNs provided good forecasting results, and WT pre-processing of input data led to even better forecasts. Additionally, it was found that meteorological variables did not have a significant impact in forecasting water-level fluctuations. In light of the results and the limited scope of the present study, proposed future research directions and problems to be resolved are discussed.

4

Lidar and ground penetrating radar data in determining road surface conditions and geological characteristics of unstable soils

Plichta A., Piasecki A.

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2017

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nr 20(2)

111--129

EN

Within the road investments the very important element determining repeatedly the success of the whole project is an adequate information about the characteristics of the site, its load capacity, stability and the possible impact of geological characteristics that may interfere with subsequent service life, not only for the road surface itself, but also for the surrounded objects. The surface is incessantly influenced by geological characteristics, determining its durability and functional usefulness. The main aim of this paper is to answer the question how by the usage of modern technics for obtaining data it is possible to find a link confirming the characteristics of land on which the specific road projects are supposed to be carried out, or where these projects have already been accomplished, concerning their requirements with high accuracy of location and also the stability and durability of the ground. This article makes also an attempt to answer not only the question how to identify the construction of road surface, but also how to locate underground cavities, created or influenced by the flow of water, or due to geological structures characterized as an inconsistent ground. The results were supported with geophysical researches using GPR method, and also data collected with laser scanners.

5

Surface morphology of wheels in rail vehicles in urban transport

Paczkowska M., Wojciechowski Ł., Piasecki A.

Journal of Achievements in Materials and Manufacturing Engineering

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2017

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Vol. 83, nr 1

12--20

EN

Purpose: The general purpose of presented research was evaluation of surface morphology of chosen tram wheels: LUCCHINI (of Siemens Combino tram), PST (of Moderus Beta tram), and GT no 1 (of Duewag tram) operating in Poznan agglomeration. Design/methodology/approach: 3D surface profile study, macro and microscopic research with light and scanning electron microscopes, and Vickers hardness measurements were done. Findings: Wear effects were observed on the rolling surface, as well on the surface of the top of the wheel flange. Rolling contact fatigue was dominant type of wear. Abrasion was also noticed, especially on the top of the wheel flange. Changes in the surface layer were also noticed, like sever plastic deformation as: overhangs, flattened grains and delamination. Plastic deformation was the reason of hardness increase. Though the rolling surface is the surface responsible for the load transfer, more plastically deformed was the surface layer of the top of the wheel flange. Although investigated wheels was operated in different trams wear effects were similar. Research limitations/implications: The research represents part of a project considering identification of phenomena occurring in the contact zone between tram wheel and the rail funded by the National Centre for Research and Development of the LIDER program. Further research should concentrate on designing of the new wheel (new profile and modified material). Practical implications: On the base of performed research it also was possible to determine some suggestions in the order to extend tram wheel life. Originality/value: The surface morphology of tram wheels has been describe quantitatively on the base of 3D roughness parameters. Main type of wear that dominate in case of chosen tram wheels in Poznan agglomeration was identified. Main material changes in the surface layer were described in those wheels.

6

Effect of diffusion borochromizing on microstructure, microhardness and corrosion resistance of tool steel with different carbon content

Bartkowska A., Bartkowski D., Piasecki A.

Journal of Achievements in Materials and Manufacturing Engineering

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2017

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Vol. 80, nr 2

49--55

EN

Purpose: The aim of this paper is presents the study results concerning influence of carbon content on the surface layer condition, microstructure, microhardness and corrosion resistance of diffusion borochromized layer. Design/methodology/approach: In paper the three types of tool steel were analysed: CT90, 145Cr6 and 165CrV12. The borochromzing process was carried out in a powder mixture containing B4C, Fe-Cr, Al2O3 at temperature 950°C for 6 h. The source of chromium was Fe-Cr while the source of boron was B4C. Findings: As a result of borochromizing process the layer with microstructure similar to boronized layer was obtained. The thickness of the resulting surface layer was dependent on the carbon content of steel. Microhardness of the borochromized layer was similar to the microhardness of the boronized layer. Additionally the corrosion resistance tests in 5% NaCl solution were performed using a potentiodynamic method. It was found that the best corrosion resistance was characterized a layer on the steel with less carbon content. Originality/value: Value of the paper is analysis of corrosion resistance by potentiodynamic method of the tool steel with borochromized layer.

7

Microstructure and selected properties of Fe–B coatings reinforced with B4C and Si particles produced by laser cladding using Yb:YAG disk laser

Bartkowski D., Bartkowska A., Piasecki A., Matysiak W.

Inżynieria Materiałowa

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2017

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Vol. 38, nr 3

137--142

EN

The paper presents the study results of Fe–B coatings produced on C45 steel using laser cladding with powder technology. For this purpose, 5-axis CNC laser machining center equipped with Yb:YAG disk laser with a power rating of 1 kW and three streams powder feeding system. The powder that was used to produce Fe–B coatings was subsequently modified by the particles of boron carbide B4C and Si particles. The resulting powder mixture to the particles included 25 wt % respectively 20% B4C, 5% Si. During these studies a laser beam power of 600 W and variable scanning speed 600 mm/min, 800 mm/min and 1000 mm/min were used. Thickness and microhardness of coatings were investigated and relationship between these properties and microstructure of the applied production parameters were described. The microstructure of producing coatings was characterized by dendritic shape. It was found that boron carbide particles and silicon particles have significant influence on increase the microhardness of produced coatings. Coatings were produced using the prepared powder mixture allowed to obtain more than twice greater microhardness than in case of coatings produced using only the Fe–B powder. Phase composition was examined by XRD. Phases of Fe3B, Fe5Si3, Fe2Si and SiB6 were identified. The influence of B4C and Si particles in the mixture of powder on the corrosion resistance of produced coatings were discussed. It was found gradual reduction of corrosion resistance with decreasing scanning speed of laser beam. Less scanning speed result in less intense interaction of laser beam on the material. As a result of this, the remelting degree of powder material with steel substrate was smaller. The surface condition after corrosion tests were examined using a scanning electron microscope. This paper also shows a calculation related to the power density of the laser beam, interaction time of beam on material and fluence.

PL

W pracy przedstawiono wyniki badań wpływu laserowego napawania proszkami Fe–B wzmocnionymi cząstkami B4C i Si. Analizowano mikrostrukturę, mikrotwardość oraz odporność korozyjną wytworzonych powłok. Celem pracy było określenie wpływu cząstek B4C i Si na wybrane właściwości.

8

Laser boriding of 100CrMnSi6–4 steel using BaF2 self-lubricating addition

Piasecki A., Kotkowiak M., Kulka M.

Inżynieria Materiałowa

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2017

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Vol. 38, nr 3

143--148

EN

100CrMnSi6–4 steel, being a high carbon chromium steel with increased content of manganese and silicon, is commonly used in the bearing industry as a standard material. This material is predominantly applied to elements of rolling bearings taking into consideration its good wearability as well as good resistance to contact fatigue. The diffusion boronizing was a thermochemical treatment which improved tribological properties of this steel. In this study, instead of the diffusion process, the laser boriding was used in order to produce a boride layer on this material. The two-step process was used during laser alloying. First, the surface of the specimen was coated by a paste with alloying material. The alloying material consisted of the mixture of amorphous boron and BaF2 as a self-lubricating addition. Next, the surface was remelted by a laser beam using TRUMPF TLF 2600 Turbo CO2 laser. The microstructure of the layer consisted of the remelted zone with eutectic mixture of iron borides, borocementite and martensite as well as the heat-affected zone with martensite, bainite and retained austenite. The continuous laser-borided layer was obtained at the surface. It was uniform in respect of the thickness because of the high overlapping used during the laser treatment (86%). The hardness decreasing was observed in remelted zone compared to the laser-alloyed layer with boron only. However, the significant increase in wear resistance of laser-borided layer was caused by BaF2 self-lubricating addition. The formation of tribofilm on the worn surface was the reason for improved tribological properties of the self-lubricating layer.

PL

Celem pracy było wytworzenie warstw stopowanych borem i fluorkiem baru charakteryzujących się zwiększoną odpornością na zużycie przez tarcie. Wśród wielu metod zmniejszenia współczynnika tarcia w parze trącej istotne znaczenie ma stosowanie olejów. Jednak ze względu na problem z nimi związany, na każdym etapie użytkowania, od produkcji po utylizację, duże znaczenie zyskują lubrykanty stałe. Substancje te można podzielić m.in. na: metale, tlenki, fluorki, siarczki, siarczany, wolframiany. Wśród tych związków na szczególną uwagę zasługują fluorki CaF2 i BaF2, które mogą pracować w wysokiej temperaturze, zapewniając zmniejszenie współczynnika tarcia. Fluorek baru charakteryzuje się małą twardością i bardzo dobrymi właściwościami smarnymi. W niniejszej pracy wytworzono warstwę stopowaną laserowo borem i fluorkiem baru, w wyniku czego spodziewano się uzyskać warstwę o większej odporności na zużycie przez tarcie, nawet przy zmniejszonej twardości w porównaniu z warstwą stopowaną laserowo wyłącznie borem. Warstwy powierzchniowe wytworzono na stali łożyskowej 100CrMnSi6–4. Stal ta charakteryzuje się zwiększoną hartownością oraz należy do stosunkowo tanich materiałów.

9

Analiza opłacalności ekonomicznej pozyskiwania wód opadowych

Piasecki A., Jurasz J.

Gaz, Woda i Technika Sanitarna

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2017

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Nr 1

23--25

PL

Długookresowe susze bądź krótkookresowe intensywne opady są zjawiskami generującymi istotne problemy na obszarach zurbanizowanych. Względy ekonomiczne przy jednoczesnym wzroście świadomości ekologicznej społeczeństwa powodują coraz większe zainteresowanie wykorzystaniem wód opadowych przez indywidualne gospodarstwa domowe. W pracy dokonano oceny ekonomicznej opłacalności inwestycji związanej z pozyskaniem i wykorzystaniem wody opadowej przez gospodarstwa domowe w wybranych miastach w Polsce. W oparciu o uzyskane wyniki wskaźnika NPV stwierdzono, że największe uzasadnienie ekonomiczne ma pozyskiwanie i wykorzystanie wód opadowych w Poznaniu. Jednak po uwzględnieniu uwarunkowań lokalnych wskazano na ograniczenia dotyczące tej lokalizacji. Zwrócono uwagę na perspektywiczne możliwości realizacji tego typu inwestycji we Wrocławiu. Uznano, że aktualnie zasadniczymi czynnikami wpływającymi na opłacalność inwestycji w zakresie pozyskiwania wód opadowych są charakter i wysokość opłaty za odprowadzanie wód opadowych.

EN

Extreme weather phenomena, and among them floods, heavy rains or long-lasting droughts result in severe problems in the urbanized environment due to the water excess or deficit. Economic reasons and the increasing ecological awareness lead to a situation when more and more households are interested in utilizing rainwater. The aim of this paper is to assess the profitability of harvesting and using rainwater by households located in selected cities in Poland. Calculated Net Present Value (NPV) indices shows that among selected locations, Poznan is a city where rainwater harvesting systems have the biggest economic justification. However after taking into account the local situation some limitations concerning this site have been pointed out. Such systems have long-range opportunities to be put into practice in Wroclaw. Also it has been found that factors affecting cost-effectiveness of rainwater harvesting systems are the specification and value of the rainwater discharging fees.

10

Economic and ecological aspects of rainwater reclamation in cities

Piasecki A., Jurasz J.

Ekonomia i Środowisko

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2017

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nr 1

171--180

EN

The aim of this paper was to investigate the economic and ecological benefits of rainwater utilization in urban areas. The case of Toruń. Conducted analysis has shown that in case of individual households which roof surface ranges from 100 to 150 m2 there is no economic justification for rainwater reclamation. With the exception of one variant, with the roof surface equal to 150 m2 and annual sum of precipitation significantly higher than the mean observed in Toruń. However, from the perspective of the whole city such projects may lead to significant financial and ecological benefits. It therefore seems essential for municipalities and environmental protection organizations to establish special programs, financially supporting such projects.

11

Piston assembly in the most powerful 2.0l diesel engine – case study of the current tribological system and innovative concepts for the future

Kałużny J., Merkisz J., Stepanenko A., Wróblewski E., Gapiński B., Piasecki A., Gallas D.

Combustion Engines

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2017

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R. 56, nr 4

127--133

EN

This article is a contribution to the ongoing debate on the scenario of the vehicle powertrains development. The directions of the internal combustion engines development in search of the possibility of effective economic and ecological indicators improvement have been indicated. It has been pointed out that this goal can be achieved through the use of nanotechnology in order to exceed the downsizing barriers resulting from the permissible mechanical loads for conventional materials. The article presents the study of the construction and materials used in the piston assembly of the most advanced four-cylinder, compression-ignition diesel engine currently in manufacture. Original concepts of nanotechnology have been proposed to reduce friction losses in major friction components of future engines with extremely high loads. The main idea is to verify the hypothesis that the sub-micron surface texture of the friction components obtained in the process of applying anti-wear outer layers can lead to an effective reduction of friction losses under real engine operating conditions. Computer simulations of the effects of introducing the surface texture in the upper sealing ring on friction loss confirm this hypothesis by showing friction value being reduced by 3-4% relative to the standard ring profile. In the summary, further advanced technologies designed to effectively utilize the unique properties of carbon nanotubes have been described.

12

The influence of sodium chlorides fog on corrosion resistance of heat exchangers used in automotive

Peta K., Grochalski K., Piasecki A., Żurek J.

Archives of Mechanical Technology and Materials

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2017

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Vol. 37

45--49

EN

In the work, the most important factors which influence on the exploitative durability of heat exchangers are classified. Particular attention was paid to the compounds of sodium chloride used in the winter season for road maintenance. In order to determine their impact on automotive heat exchanger corrosion resistance, a test of heaters in a salt chamber which imitates the conditions of their work was realized. It also allows to verify the durability of these products. To evaluate the corrosion changes, observation with the use of light microscopy and scanning microscopy SEM were made supplemented with microanalysis of chemical composition by EDS spectroscopy method. Critical areas in the heat exchangers which are mostly exposed to damage including the formation of local corrosion pits were located and analyzed.

13

The effect of CaF2 and BaF2 solid lubricants on wear resistance of laserborided 100CrMnSi6-4 bearing steel

Piasecki A., Kotkowiak M., Kulka M.

Archives of Materials Science and Engineering

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2017

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Vol. 86, nr 1

15--23

EN

Purpose: In this paper, laser alloying with boron and solid lubricants was used in order to produce the self-lubricating layer on 100CrMnSi6-4 bearing steel. The influence of CaF2 and BaF2 on microstructure, hardness, chemical and phase composition as well as wear resistance of the layers was studied. Design/methodology/approach: The two-step process was used during laser alloying. First, the surface of the specimen was coated by a paste with alloying material. The alloying material consisted of the mixture of amorphous boron and self-lubricating additions (CaF2 and BaF2). Next, the surface was re-melted by a laser beam using TRUMPF TLF 2600 Turbo CO2 laser. The laser beam power 1.43 kW was used for laser alloying. The layer was characterized using X-ray diffraction, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, microhardness tester. The dry sliding wear behaviour of the layer was investigated using the Amsler type wear test. Findings: The tribofilm, consisting of solid lubricants, was observed on the worn surfaces of laser-alloyed layers. It caused an increase in the wear resistance at room temperature. The presence of calcium fluoride and barium fluoride was confirmed in laser-alloyed layers using XRD and X-ray microanalysis by EDS method. Practical implications: Laser surface modification with solid lubricants had the important cognitive significance and gives grounds to the practical employment of this technology for reducing the abrasive wear. Originality/value: The wear mechanism of surface layer with solid lubricants was determined. The produced layer with laser alloying layers of boron and solid lubricant (CaF2 or BaF2) was compared.

14

Wymiana ciepła podczas wrzenia FC-72 w przepływie przez wymiennik ciepła z minikanałem modelowana funkcjami Trefftza i z wykorzystaniem programu ADINA

Piasecki A., Łabędzki P., Hożejowska S., Piasecka M.

TTS Technika Transportu Szynowego

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2016

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R. 23, nr 12

186--190

PL

Praca dotyczy wymiany ciepła podczas wrzenia czynnika chłodniczego FC-72 przepływającego przez wymiennik ciepła z minikanałem prostokątnym o powierzchni rozwiniętej. Akwizycję temperatury na zewnętrznej powierzchni grzejnej umożliwiło zastosowanie kamery termowizyjnej. W pracy zaproponowano dwuwymiarowy matematyczny model opisujący zagadnienie odwrotne wymiany ciepła w module pomiarowym. W oparciu o wyniki eksperymentu wyznaczono rozkłady temperatury powierzchni grzejnej oraz czynnika chłodniczego, co w dalszej kolejności umożliwiło wyznaczenie lokalnych współczynników przejmowania ciepła na styku płyty grzejnej i płynu FC-72. Lokalne współczynniki przejmowania ciepła wyznaczono również z metody jednowymiarowej. Obliczenia numeryczne wykonane metodą Trefftza zweryfikowano z wynikami otrzymanymi w programie ADINA oraz z wynikami z metody jednowymiarowej.

EN

The present paper focuses on flow boiling heat transfer with FC-72 in a heat exchanger containing a rectangular minichannel with structured surfaces. An infrared camera recorded temperatures at the external heated surface. The results of the experiments were used to model heat transfer in the minichannel by Trefftz functions and with the aid of the ADINA program. The heat transfer mathematical model was proposed. The model described the inverse heat transfer problems in the measurement module and allowed determining local heat transfer coefficients at the interface between the heated plate and FC-72 in the minichannel. Numerical calculations performed with the Trefftz functions were verified with the results obtained both from the ADINA program and from one dimensional method.

15

Wpływ zmienności temperatury na zapotrzebowanie na moc elektryczną w Polsce w latach 2002-2015

Jurasz J., Mikulik J., Piasecki A.

Przegląd Elektrotechniczny

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2016

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R. 92, nr 9

257--261

PL

Zmiana bądź zmienność klimatu jest jednym z czynników kształtujących przebieg zapotrzebowania na energię. Temperatura jest tutaj postrzegana jako czynnik o największym wpływie oraz znaczeniu w prognozowaniu popytu na energię. Przeprowadzona analiza wskazuje, że przebieg zapotrzebowania na energię elektryczną w Polsce powoli się zmienia a wpływ dni cieplejszych zaczyna być coraz wyraźniej dostrzegalny.

EN

Climate change/variability is one of the factors that affects the pattern of electrical energy consumption. Where the temperature is perceived as dominant and of crucial role in demand forecasting. Conducted analysis shows that energy demand pattern in Poland is slowly changing, and the impact of warmer days becomes more distinguishable.

16

Projekt zdalnego sterowania budynkiem z wykorzystaniem technologii Bluetooth

Piasecki A., Trzmiel G.

Poznan University of Technology Academic Journals. Electrical Engineering

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2016

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No. 87

179--189

PL

W pracy odniesiono się do tematu zdalnego sterowania wybranymi elementami budynku mieszkalnego za pomocą technologii Bluetooth z wykorzystaniem urządzenia mobilnego. Na początku pracy scharakteryzowano bezprzewodową transmisji danych poprzez Bluetooth. Kolejna część poświęcona jest projektowi budynku oraz układu elektronicznego opierającego się na mikrokontrolerze z rodziny ATmega, komunikującego się z urządzeniem mobilnym poprzez bezprzewodową transmisję danych w standardzie Bluetooth. Projekt zawiera sterowanie oświetleniem, roletami, wentylatorem oraz bramą garażową. Sterowanie opiera się na układzie składającym się z triaka oraz optotriaka. Wykonano również aplikację sterującą na system Android, aby możliwe było sterowanie budynkiem z urządzenia mobilnego.

EN

In this paper, references is made to the subject of remote control of certain parts of a residential building via Bluetooth using the mobile device. First, wireless data transmission via Bluetooth is described. Then, the paper deals with the design of the building and the electronic system based on a microcontroller ATmega family that communicates with a mobile devices via Bluetooth wireless data transmission. The project includes lightning, window blinds, a fan and a garage door. The control is based on a system consisting of a triac and on optotriac. In addition, a control application for Android system is created to enable a remote control with a mobile device.

17

Wykorzystanie wielowarstwowych sztucznych sieci neuronowych do średnioterminowego prognozowania poboru wody – studium przypadku

Piasecki A., Jurasz J., Marszelewski W.

Ochrona Środowiska

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2016

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Vol. 38, nr 2

17--22

PL

Do prognozowania miesięcznego poboru wody w wybranym mieście o średniej wielkości wykorzystano wielowarstwowe sztuczne sieci neuronowe. Badaniem objęto jedno z osiedli w Toruniu – Czerniewice, które ma własny system wodociągowym (inny niż pozostała część miasta). Początkowo w analizie uwzględniono dziewięć zmiennych objaśniających, opisujących warunki meteorologiczne, ekonomiczne i społeczne. W trakcie prognozowania okazało się, że wykorzystanie wszystkich zgromadzonych zmiennych wejściowych korelujących z poborem wody nie dało prognoz najlepszych jakościowo. Najlepszy wynik w tym zakresie (oceniony na podstawie wartości błędu typu MAPE) uzyskano w przypadku modelu zbudowanego na podstawie takich zmiennych, jak liczba osób korzystających z wodociągu, cena wody, maksymalna temperatura i wilgotność powietrza oraz średni dochód na jednego mieszkańca. Wykazano, że zakres zmiennych uwzględnianych w prognozowaniu poboru wody za pomocą sieci neuronowych wymaga dostosowania do warunków lokalnych. W rozpatrywanym przypadku sztuczne sieci neuronowe potwierdziły swą użyteczność w zakresie średnioterminowego prognozowania poboru wody.

EN

Multilayer perceptron (MLP) artificial neural networks were employed to monthly water consumption forecasting. Research encompassed Czerniewice, one of the estates in Torun with a dedicated waterworks system (different from the other part of the town). Initially, nine exogenous variables describing meteorological, economic and social conditions were examined. The forecasting process revealed that implementation of all input variables correlating with water consumption did not lead to the highest quality forecasts. In terms of quality, the best result (evaluated based on MAPE criterion) was achieved for a model built on variables such as number of residents with access to waterworks, water rate, maximum temperature and humidity, and average income per inhabitant. It was demonstrated that the selection of input variables used for water consumption forecasting should be adjusted to local conditions. In the example considered, artificial neural networks proved useful in mid-term water consumption forecasting.

18

Dynamics of the daily course of water temperature in Polish lakes

Skowron R., Piasecki A.

Journal of Water and Land Development

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2016

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no. 31

149--156

EN

The study focuses on short-term changes in surface water temperature in Polish lakes, and is based upon the experimental measurements of water temperature conducted every 60 minutes during the years 1971–2015. 19 lakes were selected on the grounds of their morphometric properties. The examinations were carried out in the system of expeditionary measurements (up to 8 days) and stationary measurements (over 2 months), and included temperature of surface water and its vertical distribution. The analysis of the results showed that temperature differences of water (daily amplitudes) were observed in both time and spatial distribution. The biggest differences in water temperature occurred during spring warming, and often reached 4–5°C, while rarely exceed 2°C in the remaining periods of the yearly cycle. The mean day value occurs twice; in the morning between 8:00 (7:00 GMT) and 11:00 (10:00 GMT), and in the evening at 20:00 (19:00 GMT) and 22:00 (21:00 GMT). Daily changes in the vertical distribution of water temperature are clearly visible down to the depth of 2.5–3.5 m, whereas are just perceptible to the depth of 5.5–7.0 m.

PL

Praca dotyczy krótkotrwałych zmian temperatury wody powierzchniowej w jeziorach w Polsce. Została ona opracowana na podstawie eksperymentalnych pomiarów temperatury wody prowadzonych co 60 minut w latach 1971–2015 w 19 jeziorach wytypowanych na podstawie cech morfometrycznych. Badania prowadzono w systemie pomiarów ekspedycyjnych (do 8 dni) i stacjonarnych (ponad 2 miesiące) i obejmowały temperaturę powierzchniową wody oraz jej pionowy rozkład. Na podstawie analizy wyników stwierdzono różnice temperatury wody (amplitudy dobowe) zarówno w rozkładzie czasowym, jak i przestrzennym. Największe różnice temperatury wody występowały w okresie wiosennego nagrzewania i często osiągały 4–5°C, natomiast w pozostałych okresach cyklu rocznego rzadko przekraczały 2°C. Na podstawie cogodzinnych pomiarów temperatury wody można stwierdzić, że temperatura przed południem między godziną 8:00 a 11:00 (7:00 a 10:00 GMT) oraz późnym wieczorem w godzinach 20:00–22:00 (19:00–21:00 GMT) była najbardziej zbliżona do średniej dobowej. Zmiany dobowe w rozkładzie pionowym temperatury wody wyraźnie zaznaczają się do głębokości 2,5–3,5 m, natomiast dostrzegane są do głębokości 5,5–7,0 m.

19

Laser alloying of 316L steel with boron using CaF2 self-lubricating addition

Mikołajczak D., Piasecki A., Kulka M., Makuch N.

Inżynieria Materiałowa

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2016

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Vol. 37, nr 1

4--9

EN

Good resistance to corrosion and oxidation of austenitic 316L steel is well-known. Therefore, this material is often used wherever corrosive media or high temperature are to be expected. However, under conditions of appreciable mechanical wear (adhesive or abrasive), this steel have to characterize by suitable wear protection. The diffusion boronizing can improve the tribological properties of 316L steel. However, the small thickness of diffusion layer causes the limited applications of such a treatment. In this study, instead of diffusion process, the laser boriding was used. The external cylindrical surface of base material was coated by paste including amorphous boron and CaF2 as a self-lubricating addition. Then the surface was remelted by laser beam. TRUMPF TLF 2600 Turbo CO2 laser was used for laser alloying. The microstructure of remelted zone consisted of hard ceramic phases (iron, chromium and nickel borides) located in soft austenite. The layer was uniform in respect of the thickness because of the high overlapping used during the laser treatment (86%). The obtained composite layer was significantly thicker than that-obtained in case of diffusion boriding. The remelted zone was characterized by higher hardness in comparison with the base material. The significant increase in wear resistance of laser-borided layer was observed in comparison with 316L austenitic steel which was laser-alloyed without CaF2.

PL

Stal austenityczna 316L jest znana z dużej odporności na korozję i utlenianie. Dlatego materiał ten jest stosowany często tam, gdzie jest spodziewane agresywne środowisko lub wysoka temperatura. Jednakże w warunkach znacznego zużycia mechanicznego (ściernego czy adhezyjnego) materiał ten powinien charakteryzować się odpowiednią odpornością na zużycie. Celem pracy było przeprowadzenie stopowania laserowego stali 316L z zastosowaniem materiału stopującego w postaci mieszaniny amorficznego boru i dodatku samosmarującego CaF2. Bor amorficzny miał prowadzić do wytworzenia w strefie przetopionej twardych borków żelaza, chromu i niklu — podstawowych pierwiastków występujących w stali 316L. Spodziewano się znacznego zwiększenia twardości oraz odporności na zużycie przez tarcie wytworzonej warstwy powierzchniowej w porównaniu ze stalą 316L nie poddaną żadnej obróbce. Zastosowanie dodatku samosmarującego w postaci fluorku wapnia miało prowadzić do jeszcze większej odporności na zużycie dzięki wytworzeniu na żużywającej się powierzchni tribofilmu.

20

Analysis of rate and structure of water consumption in rural areas of selected counties of the Kuyavian-Pomeranian voivodeship

Piasecki A., Jurasz J.

Infrastruktura i Ekologia Terenów Wiejskich

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2016

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nr IV/2

1411--1421

EN

Over recent years, the structure and rate of water consumption in Poland has exhibited significant changes. In urban areas has been observed a substantial decrease in water demand, whereas in rural areas the general trend has been the opposite. The aim of this work was to investigate the consequences of changes in area of water and sewage management in Bydgoski, Toruński and Włocławski counties, paying special attention to the rate and structure of water consumption. In this study were used data from the Central Statistical Office of Poland (GUS). The data included information concerning the length of waterworks system, and the rate and structure of water consumption in individual communes of the investigated counties. In 22 out of 28 examined units was recorded an increase of total and individual water consumption. Selected communes and rural areas have significant differences in rate and structure water consumption. The main cause of these changes are indicated to be an increase in population (migration from cities) accompanied by an expansion of waterworks.