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U završnom radu opisana je povijest i sva glavna postrojenja TE-TO Osijek. Termoelektranatoplana Osijek sastoji se od nekoliko blokova koji zajedno imaju funkciju proizvodnju i distribuciju električne i toplinske energije. Steamblok kotlovnica (SBK) sastoji se od 3 parna kotla koji služe samo za proizvodnju toplinske energije, dok plinsko turbinska elektrana zajedno sa KNOT-om ima zadaću proizvoditi i toplinsku i električnu energiju. Glavni blok snage 45MW zajedno sa dva visokotlačna kotla, parnom turbinom i generatorom - najveći je i najmoćniji u pogonu za proizvodnju toplinske i električne energije. BE-TO Osijek kao najnoviji pogon u Osijeku, pogonjen na šumsku biomasu ima zadaću proizvoditi paru za parne potrošače, proizvoditi električnu energiju i podignuti temperaturu vode kod povrata vrelovoda. In the final paper, the history and all the main plants of TE-TO Osijek are described. Osijek thermal power plant consists of several blocks that together have the function of producing and distributing electricity and heat energy. The steam block boiler room (SBK) consists of 3 steam boilers that are used only for the production of heat energy, while the gas turbine power plant, together with the KNOT, has the task of producing both heat and electricity. The main unit with a power of 45MW, together with two high-pressure boilers, a steam turbine and a generator - is the largest and most powerful in the plant for the production of heat and electricity. BE-TO Osijek, as the newest plant in Osijek, powered by forest biomass, has the task of producing steam for steam consumers, producing electricity and raising the temperature of the water at the return of the hot water pipe.

Prekrcajna sredstva obuhvaćaju vrlo važnu temu kada je u pitanju proučavanje prometa i sve što je u vezi s njim. Njih ne možemo vezati za vrijeme, jer vremenom dolazi do razvoja tehnike i tehnologije pa će samim tim i vrsta i razvoj prekrcajnih sredstava dobijati novu dimenziju u procesu egzistiranja. U prvom djelu ovog rada napisano je općenito o tankerima, o njihovom razvoju, konstrukcijskim karakteristikama, te o radnjama i postupcima koje su značajne za siguran ukrcaj, iskrcaj te prijevoz. Drugi dio je posvećen prekrcajnim sredstvima na tankerima za prijevoz sirove nafte, njihovim vrstama, konstrukcijskim karakteristikama, opremi, sustavima koje sadrže te o ostalim radnjama za njihovu eksploataciju. U zaključnome dijelu ovoga rada opisan je proces prekrcaja sirove nafte. Transhipment means comprise a very important topic when it comes to the study of traffic and everything about him. They can't be related to the time, because with time comes to the development of techniques and technologies and therefore, species and the development of transhipment funds receive a new dimension in the process of existence. In the first part of this paper we will talk in general about the tankers, their development, design characteristics, and the actions and procedures which are important for safe loading, unloading and transport. The second part is dedicated to transhipment means of tankers to transport crude oil, their types, design characteristics, the equipment, containing systems and the other actions for their exploitation. In the final part of this paper, the process of transshipment of crude oil is described.

U radu Sustav goriva za termoelektranu opisan je sustav goriva Termoelektrane Rijeka. Rad je podijeljen u dvanaest poglavlja. Na početku rada opisuju se postrojenja s parnim procesima i prikaz potrošnje električne energije u Hrvatskoj. Navedeni su i opći podatci o Termoelektrani Rijeka kao što su povijest izgradnje, odabir lokacije, odabir goriva i shema postrojenja termoelektrane. U središnjem dijelu rada detaljno se opisuje sustav goriva Termoelektrane Rijeka. Opisan je transport ulja kroz termoelektranu od prihvata goriva do njegovog izgaranja u glavnom kotlu. Prikazan je i sustav skladištenja i zagrijavanja goriva. Opisane su pumpe koje se pri tom koriste, a to su centrifugalna pumpa i vijčana pumpa. Preko sastava goriva i tehničkih podataka za glavni kotao izračunata je potrošnja goriva. U završnom dijelu rada, na temelju sheme priložene u radu, izračunata je potrebna snaga pumpi, a preko kataloga proizvođača odabrana je pumpa na temelju visine stupca fluida i protoka. Na kraju su rada priloženi laboratorijski izvještaj o kvaliteti goriva, shema prihvata goriva i shema pripreme goriva.

Das Cordier-Diagramm stellt den empirischen Zusammenhang zwischen optimaler Laufzahl und Durchmesserzahl dar, der aus den mit dem besten Wirkungsgrad arbeitenden einstufigen Str��mungsmaschinen ermittelten Informationen erstellt wird. Neue Forschungsarbeiten stellen dar, dass die Energieumsetzung die grunds��tzliche Ursache f��r die Entstehung der Cordier-Linie ist. Aus diesem Grund wurde erzielt, die Energieumsetzung der Tesla-Turbomaschinen in das Cordier-Diagramm einzutragen. Die Tesla-Turbomaschinen bzw. Reibungsturbomaschinen weisen gegen��ber den konventionellen Str��mungsmaschinen keine str��mungsumlenkenden Schaufeln auf. Um die Str��mungswinkeln festzulegen, m��ssen die Geschwindigkeitsprofile in Betracht gezogen werden. Daf��r ist die Berechnungsvorschrift von K��hler hilfreich, welche auf Basis der Wandschubspannungen auch die Bestimmung des Spaltwirkungsgrades bzw. Umfangswirkungsgrades erm��glicht. Mit Hilfe dieses Modells wurde die Energieumsetzung f��r verschiedene Laufradgeometrien und Betriebsbedingungen berechnet und in das Cordier-Diagramm eingetragen., The Cordier-Diagram, which is plotted by utilising the data collected by best single stage fluid flow machines, illustrates the empirical relationship between optimum speed number and diameter number. Recent research studies state that the basis of Cordier-Line is the energy transfer. Unlike the conventional fluid flow machines, Tesla-Turbomachines (also called as friction turbomachines) do not have flow diversion blades, thus velocity profiles are needed in order to establish the flow angles. Therefore K��hlers calculation rule becomes helpful. This calculation rule allows us to determine the energy-transfer efficiency (also called as circumferential efficiency) based on wall shear stresses. The energy transfer of several rotor geometries and operating conditions are calculated with the aid of K��hler-Model and plotted in the Cordier-Diagram.

eingereicht von Marcus Andreas Hintermüller BSc Kurzfassungen in deutscher und englischer Sprache Universität Linz, Univ., Masterarbeit, 2016

Rad se bavi objašnjenjem i usporedbom proračunskih postupaka za određivanje uvjeta koji moraju biti zadovoljeni na usisnoj strani pumpe da ne bi nastupilo kavitiranje. Kako je u literaturi vrlo čest algoritamski pristup propisivanja proračunskih koraka bez mnogo objašnjavanja, ovdje je učinjen pokušaj popunjavanja te praznine., This paper strives to explain and compare analytical procedures used to provide cavitationfree operation of pumps. Approach in most of literature is algorithmic, without necessary explanations. Therefore, an attempt is made to fill that gap.

Dovod vode i njena filtracija uključuje sve uređaje i strojeve kojima se vrši mehanička i kemijska obrada pitke izvorske vode „Studena“. U tehničkom je postrojenju tvornice smješten skup strojeva za proizvodnju i flaširanje pitke vode, kao i sve pumpe kojima je omogućen neprestani dovod vode. Sinkronizirani rad svih sustava stvara proizvod koji konkurira na globalnom tržištu. The water supply and its filtration includes all devices and machines that are used for mechanical and chemical processing of drinking spring water "Studena". Set of machines for production and bottling of drinking water, as well as all the pumps which allow continuous water supply are situated in the technical part of the plant of the company. Synchronized operation of all systems create a product that competes in the global market.

Energetska učinkovitost je suma isplaniranih i provedenih mjera čiji je cilj korištenje minimalno moguće količine energije tako da razina udobnosti i stopa proizvodnje ostanu sačuvane. Pasivna kuća je energetski najštedljiviji oblik niskoenergetske građevine. Svojim oblikom, debljinom toplinske izolacije, vrstom i veličinom otvora kao i njihova ostakljenja te ugradnjom uređaja za iskorištavanje topline zemlje ili podzemnih voda ostvaruje ugodno stanovanje i zimi i ljeti bez uobičajenih sustava za grijanje i klimatizaciju. Također, u praksi se ugrađuju i uređaji za ventilaciju sa iskorištavanjem topline otpadnog zraka – rekuperatori. Energijski pozitivna zgrada je napredniji oblik energetski neovisne kuće koja priključak na javnu električnu mrežu koristi isključivo za plasman viška proizvedene električne energije koju prodaje te u svojoj osnovi, zahvaljujući primjeni obnovljivih izvora energije funkcionira kao elektrana. Energy efficiency is the sum of planned and implemented measures whose aim is to use the minimum possible amount of energy so that the comfort level and rate of production are preserved. Passive house is the most economical form of energy low building. Its shape, thickness of the thermal insulation, type and size of openings and their glazing, also installation of devices for using the heat of earth or groundwater achieves comfortable housing in winter and summer without the usual system for heating and air conditioning. Also, in practice, is implanted and ventilation units with heat recovery exhaust air - recuperators. The energy positive building is a more advanced form of energy-independent house which connection to the electricity grid is used exclusively for the placement of surplus electricity that is sold, and in essence, through the use of renewable energy sources functions as a powerhouse.

Suhi dokovi su objekti u kojima se vrši remont ili gradnja broda. Za izgradnju ovog kapitalnog hidrotehničkog objekta potrebno je izvršiti analizu tla, ispitati utjecaj podzemnih voda te izraditi projektnu i izvedbenu dokumentaciju. Zastupljena su tri različita tipa suhog doka. Proces izgradnje odvija se na obalnom terenu ili na morskom dnu. Tijekom izgradnje koriste se mnogi elementi koji služe za ojačanje strukture, a materijal od kojeg se grade suhi dokovi armirani je beton. Tlocrt suhih dokova je pravokutnog, a poprečni presjek trapeznog ili pravokutnog oblika. Strukturu doka čine pod (kao najvažniji strukturni element), bočni zidovi, čeoni zid i vrata doka. Dno se u uzdužnom smjeru gradi sa blagim nagibom prema vratima kako bi se omogućilo lakše istjecanje vode tijekom isušivanja doka. Kako bi bili operativni, moraju imati uređaje koji služe za naplavljivanje i isušivanje, instaliran kompletan energetski sustav te sustav gradnje i opremanja. Sustav za naplavljivanje i isušivanje sastoji se od pumpne stanice, pumpi koje se koriste za različite svrhe, usisnih i odvodnih kanala te ventila. Vrata suhog doka razlikuju se dizajnom, konfiguracijom i načinom rada. Na odabir vrata koja su prikladna za određeni tip suhog doka utječu mnogi faktori. Dizalično-transportna oprema važan je dio opreme brodogradilišta zbog izgradnje brodova. Upotrebom dizalica koje imaju veći kapacitet i doseg, omogućuje se brža i efikasnija izgradnja. U ovom radu napravljen je pregled građevno-remontnih mjesta brodogradilišta s posebnim naglaskom na suhe dokove. Prikazan je cjelokupni proces osnivanja, izgradnje i opremanja suhog doka te pojednostavljena strukturna analiza betonsko-masivnog doka opterećenog tankerom za prijevoz kemikalija u izgradnji. Graving drydocks are objects that are used for repair or construction of ships. In order to construct this kind of capital hydrotechnical facility it is necessary to perform soil analysis, to examine the impact of groundwater and make elaborate project and construction documentation. Graving drydocks are usually classified into three different types. Actual building process takes place in the coastal ground or on the seabed. During the construction many elements are used for structural reinforcement, and the material from which drydocks are made is reinforced concrete. The plan view is rectangular, and the cross section is trapezoidal or rectangular in appearance. The structure of drydocks consists of dock floor, side walls, front wall and door of the dock. The bottom in the longitudinal direction is built with a slight inclination towards the door to allow easier flow of water during the drying out of the dock. To be operational, drydocks are installed with flooding and drainage system, complete energy system and the devices for construction and outfitting of ships (vertical transport system). The system for flooding and drainage consists of a pumping station, the pumps that are used for different purposes, suction and drainage channels and valves. Drydock doors can vary due to different designs, configurations and modes of operation. The selection of the door which is suitable for a certain type of dock is influenced by many factors. Vertical transport equipment (namely cranes) are an important segment in the shipyard for the construction of ships. Using a crane, which has a greater capacity and reach, allows for a faster and more efficient construction. In this thesis an outline of ship repair and shipbuilding facilities is given with emphasis on graving drydocks. The whole process of drydock design, construction and outfitting is detailed along with a simplified structural analysis of heavy graving drydock loaded with chemical tanker being built.

Suhi dokovi su objekti u kojima se vrši remont ili gradnja broda. Za izgradnju ovog kapitalnog hidrotehničkog objekta potrebno je izvršiti analizu tla, ispitati utjecaj podzemnih voda te izraditi projektnu i izvedbenu dokumentaciju. Zastupljena su tri različita tipa suhog doka. Proces izgradnje odvija se na obalnom terenu ili na morskom dnu. Tijekom izgradnje koriste se mnogi elementi koji služe za ojačanje strukture, a materijal od kojeg se grade suhi dokovi armirani je beton. Tlocrt suhih dokova je pravokutnog, a poprečni presjek trapeznog ili pravokutnog oblika. Strukturu doka čine pod (kao najvažniji strukturni element), bočni zidovi, čeoni zid i vrata doka. Dno se u uzdužnom smjeru gradi sa blagim nagibom prema vratima kako bi se omogućilo lakše istjecanje vode tijekom isušivanja doka. Kako bi bili operativni, moraju imati uređaje koji služe za naplavljivanje i isušivanje, instaliran kompletan energetski sustav te sustav gradnje i opremanja. Sustav za naplavljivanje i isušivanje sastoji se od pumpne stanice, pumpi koje se koriste za različite svrhe, usisnih i odvodnih kanala te ventila. Vrata suhog doka razlikuju se dizajnom, konfiguracijom i načinom rada. Na odabir vrata koja su prikladna za određeni tip suhog doka utječu mnogi faktori. Dizalično-transportna oprema važan je dio opreme brodogradilišta zbog izgradnje brodova. Upotrebom dizalica koje imaju veći kapacitet i doseg, omogućuje se brža i efikasnija izgradnja. U ovom radu napravljen je pregled građevno-remontnih mjesta brodogradilišta s posebnim naglaskom na suhe dokove. Prikazan je cjelokupni proces osnivanja, izgradnje i opremanja suhog doka te pojednostavljena strukturna analiza betonsko-masivnog doka opterećenog tankerom za prijevoz kemikalija u izgradnji.

Numerous recurrent situations following mixing and pumping of mortars and concretes cause degradation of fluidity and hardening characteristics. Which, in turn, lead to adverse effects on the quality of workmanship and structural defects. Nonetheless, relatively little research on the mixing and pumping energies used for the onsite transport and preparation of mortar or concrete has been directed at the core reasons or mechanisms for changes in technological properties. This dissertation describes and explains the effects of various mixing and pumping parameters on the mortar characteristics in a field trial and on a laboratory scale. Observations using a rheograph revealed that shearing action does exhibit the most pronounced influence on the characteristics of mortars during the pumping. The performed investigations indicate that higher shearing actions, for example, excessive mixing duration and long-distance pumping lead to reduced flowability, accelerated and increased hydration rate, increased early compressive strength and early-age shrinkage. From these findings, the underlying mechanism responsible for acceleration and increase of hydration rate is pinpointed as: the increased dissolution from the active surface area due to the destruction of the protective superficial layers of cement grains, as well as a transition from flocculation to dispersion. The creation of new surfaces leads to further consumption of active super plasticizer in solution phase and to subsequent degrading changes in fluidity (decreasing flowability). The degradation of fluidity and densification of microstructure provoked by the hydration changes do increase the early age shrinkage of mortar.

tema ovog završnog rada su pumpe i turbine u hidrotehničkim tokovima. Rad se sastoji od teorijskog dijela u kojem ćemo se upoznati sa povijesnim razvojem pumpi i turbina, njihovim vrstama, karakteristikama i primjeni. Također imamo primjer na kojem ćemo izračunati potrebnu snagu pumpe za savladavanje zadane visine u hidrotehničkom toku, te potrebnu razinu vodnog lica u rezervoaru da bi turbina prozvela zadanu snagu.

Ovaj članak ukratko obrađuje oblike energija kapljevitog fluida pri radu pumpnih postrojenja dinamičkih pumpi s radijalnim rotorima. One su za vatrogasnu upotrebu normirane i mogu biti trajno ugrađene na vatrogasna vozila ili su izvedene kao motorne pumpe. Oblici energija kapljevine promatrani su sa stajališta podtlaka i pretlaka koji mogu biti na ulaznoj strani pumpe te isto tako sa stajališta potencijalne energije kapljevine, odnosno energije tlaka koju kapljevina ima na tlačnom izlazu. Pri izražavanju različitih oblika energija kapljevine uvažavani su osnovni zakoni mehanike kapljevitih fluida te zakon o očuvanju energije koji se primijenjuje na fluide u kapljevitom stanju., This tekst covers fluid energy shape which uses in pump system. A pump is machine that imparts energy to a liquid to increase its pressure and move it from one point to another. There are many pump classification. One classification is acording to the method energy is imparted to the liquid: kinetic energy, or positive displacement. A centrifugal pump is of kinetic energy type because it imparts energy to a liquid by means of centrifugal force produced by a rotating impeller. Displacement pumps are of lower flow range and have pulsating flow rate. Centrifugal pump is rotodinamic pump that uses a rotating impeller to increase the pressure of liquid. They are commonly used to move liquids through a piping system. The liquid enters to the pump impeller along or near to the rotating axis and is accelerated bay the impeler, flowing radially outward into diffuser or volute chamber (casing), from where it exist into the downstream piping system. Like most pumps, a centrifugal pumps converts mechanical energy from a motor to energy of a moving fluid (liquid). Some of energy goes into kinetic energy of liquid motion and some into potential energy, represented by a liquid pressure or by lifting the liquid against gravity to higher level. The two major components of a centrifugal pumps are impeller and the casing in which it rotates. The transfer of energy from mechanical rotation of the impeller to the motion and pressure of the liquid is usually described by means of centrifugal force. Power from the driver, which is an electric motor, a diesel engine or a steam turbine (not for firefigting use) is transmitted to the pump through the shaft, rotating the impeller at high speed. In the modern centrifugal pump, most of the energy conversation is due to the outward force that curved impeller blades impart on the liquid. Invariability, some of the energy also pushes the liquid into a circular motion, and this circular motion can also convey some energy and increase the pressure at the outlet. The pumps are identified by the direction of the flow through impeller, with refernce to the axis of rotation. The total head of the pump is the energy imparted to the liquid as it passes through the pump. It may be expressed in various units of pressure, but for fire protection it’s generally given in units for pressure-bar or in units for long-m. The total head is calculated by subtracting the energy in the incoming fluid from the energy in the discharging liquid. Neto positive suction head (NPSH) is the pressure head that causes liquid to flow through the suction pipe and fitting into the eye of a pump impeller. The pump itself has no ability to ‘lift’ and the suction pressure depends on the nature of the supply. There are a two kinds of NPSH to consider. Pump NPSH is a function of the pump design and varies with the capacity and speed of any pump and with the design of different pumps. Available NPSH is a function of the system in which the pump operates and can be calculated readily. When the water source is above the pump, available NPSH is equal atmospheric pressure plus static head on suction minus friction and fitting losses in suction pipping minus vapor pressure of liquid. For any pump installation, the available system NPSH must be equal or greater than the pump NPSH at the desired operating condition. Pumps suppliers set the NPSH required (NPSHR) for a given pump. The (NPSHR) takes into account any potential head losses that might occur between the pump’ suction nozzle and impeller, thus ensuring that the liquid doesn’t drop below it’s vapour pressure.

U ovome je radu provedena analiza utjecaja izvedbe brodskih cjevovoda na mogućnost montaže i rada pumpi. Pri ugradnji cjevovoda vrlo se često pojavljuju manja ili veća odstupanja od projektnih dimenzija koja otežavaju montažu opreme poput pumpi, ventila i sl. Naknadne dorade na brodskim cjevovodima neizbježno znače velike dodatne troškove i prekoračenje predviđenog vremena ugradnje cjevovoda. S druge strane, neispravno ugrađena pumpa imat će znatno kraći radni vijek, a ako se kvar na njoj dogodi u nepovoljnom trenutku, posljedice mogu biti ozbiljne. Metodologija kojom se može provjeriti je li izmjereno odstupanje cjevovoda prije ugradnje opreme prihvatljivo, može donijeti znatne uštede pri ugradnji i eksploataciji cjevovoda. Primjenom metode konačnih elemenata moguće je relativno precizno izračunati opterećenja koja djeluju na kućište pumpe pri neispravnoj montaži. U radu je provedena analiza metodom konačnih elemenata na primjeru izabranog segmenta brodskog cjevovoda te su izračunana opterećenja na kućište pumpe kao funkcija veličine odstupanja od projektnih dimenzija.Na temelju dobivenih rezultata može se ocijeniti je li zatečeno odstupanje na realnom cjevovodu prihvatljivo ili ne. U zaključku su dane smjernice za nastavak i sistematizaciju ovog istraživanja prema potrebama i zahtjevima specifičnog tehnološkog procesa izrade i ugradnje cjevovoda., In this paper, the analysis of the ship piping installation effect on the possibility of mounting and on the operation of pumps was performed. Smaller or greater deviations from the project dimensions which complicate the mounting of the equipment, such as pumps or valves, appear frequently during the piping installation. Additional works on ship piping inevitably mean high additional costs and overrun of time limits scheduled for the piping installation. On the other hand, incorrectly mounted pump will have significantly shorter working life and if pump malfunction happens in an unfavourable moment, the consequences could be serious. Methodology, by which it could be verified if the measured piping deviation is acceptable before the equipment mounting, could yield in significant savings during the piping installation and exploitation. Loads that affect on the pump housing upon incorrect mounting could be calculated precisely by the application of the finite element method. In this paper, the finite element method analysis was performed on the example of a chosen segment of the ship piping where the pump housing loads were calculated as the function of the piping deviation from the project dimensions. On the basis of the obtained results, it is possible to evaluate whether the pre-existing condition of piping could be acceptable or not. Directives for the continuation and systematization of this research according to the needs and requirements of a specific technological piping production and installation process are given in the conclusion.

Refabrikation - das industrielle "Aus alt mach neu" ist mehr als eine profitable Lösung für Service und Instandhaltungsaufgaben. Es trägt auch zur Energie- und Ressourceneffizienz bei. Angesichts der aktuellen politischen Diskussion zur Herstellerproduktverantwortung sowie umwelt- und marktseitigen Entwicklung ist Refabrikation von hohem Interesse in der Pumpen- und Kompressorindustrie. Geprägt durch den hohen Materialanteil der Baugruppen wie Gehäuse, Läufer, Elektromotor und Getriebe ist dies von jeher fundamentales Produktoptimierungsziel dieser Branche. Speziell der Aufarbeitungsprozess und die damit ermöglichten mehrfachen Produktlebenszyklen stellen in diesem Zusammenhang sowohl aus ökologisch-ressourcenschonender als auch aus ökonomischer Sichtweise für Betreiber und Hersteller eine häufig noch nicht wahrgenommene, aber dennoch sehr vielversprechende Handlungsoption dar.

Ovim radom obrađena je izrada upravljačko – zaštitnog ormara precrpne stanice. Na temelju snaga i uvjeta rada elektromotora crpki napravljen je proračun debljine kablova, padova napona i struja kratkog spoja. Cilj je odabrati optimalnu zaštitnu opremu koja zadovoljava uvjete u normalnom radu i koja štiti korisnike i servisere od neželjenih posljedica usljed izvanrednih situacija (kvarova). Izvršen je ručni proračun, a s obzirom na dobivene rezultate odabrala se kvalitetna oprema iz ponude SCHRACK proizvoda.

eingereicht von Schitter, Wolfgang Zsfassung in engl. Sprache Wien, Univ. für Bodenkultur, Dipl.-Arb., 2011

Pumpensysteme spielen in vielen Produktionsanlagen der verfahrenstechnischen Industrie eine wichtige Rolle. Sie sind die Schlüsselkomponenten, die in hohem Maße die Verfügbarkeit der Anlagen beeinflussen. Fällt eine Pumpe plötzlich aus, kann das den Stillstand der gesamten Anlage zur Folge haben und erhebliche Kosten verursachen.

Different consequences of energy efficiency measures implementation, in low voltage installations, have been presented and analyzed. Especially, impact of energy inefficient light sources replacement by efficient lamps, and addition of variables speed drives to existing induction machines have been examined. The mentioned impacts have been analyzed on a small low voltage radial distribution network by harmonic power flow calculations. Nonlinear loads were modeled upon laboratory measurements of different compact fluorescent lamps and variable speed drives and harmonic analysis of respective current-voltage waveforms. In addition, impact of variable speed control on refrigeration machines and pumps has been examined and the results presented., U radu su obrađene neke od posljedica inherentnih sustavnom provođenju mjera za povećanje energetske učinkovitosti u niskonaponskim instalacijama zgrada. Posebno je analiziran utjecaj zamjene energetski neučinkovitih izvora svjetlosti učinkovitima te prigradnja frekvencijskih pretvarača postojećim elektromotornim pogonima. Spomenuti utjecaji analizirani su na primjeru male, radijalne distribucijske mreže pomoću metode harmoničkih tokova snaga. Nelinearni tereti modelirani su temeljem strujno-naponskih valnih oblika dobivenih laboratorijskim ispitivanjima fluokompaktnih žarulja različitih proizvođača te elektromotornih pogona s frekvencijskim pretvaračima. Također, u radu je prikazan utjecaj regulacije promjenom brzine vrtnje na pogon rashladnih uređaja i pumpi.

Describes the oldest treatise on mechanics written in Western Europe (published in 2006) and its contents on hydraulic maters: water lifting devices, construction of wells, water mills.

The mathematical model of the workflow as a set of centrifugal pump pressure pump dependency, power and torque to the drive shaft of a variable in time of a pump. The estimation of energy expenditure associated with the unstable regimes of the pump the hydraulic network. Предложена математическая модель рабочего процесса центробежного насоса как совокупность зависимостей напора насоса, мощности и момента на приводном вале от изменяющейся во времени подачи насоса. Выполнена оценка затрат энергии, связанных с неустановившимися режимами работы насоса на гидравлическую сеть. При цитировании документа, используйте ссылку http://essuir.sumdu.edu.ua/handle/123456789/1601

Mechatronische Pumpensysteme sind die treibende Kraft in fast allen Produktionsanlagen der verfahrenstechnischen Industrie und bestimmen in hohem Maße die Verfügbarkeit der Anlagen. Der Zuverlässigkeit von Pumpensystemen kommt demzufolge ein ganz besonderer Stellenwert zu. Daher wird seit Oktober 2006 im Verbundforschungsprojekt ReMain an einem weitergehenden Ansatz bezüglich Diagnose und Restlebensdauerprognose von Pumpensystemen gearbeitet.

Pumpen sind in der verfahrenstechnischen Industrie weit verbreitete Maschinen und beeinflussen in hohem Maße die Verfügbarkeit der Anlagen. Hersteller, Betreiber und Instandhalter sind daher zunehmend an Möglichkeiten zur Störungsfrüherkennung und Zustandsüberwachung interessiert. Im Verbundforschungsprojekt ReMain wurde ein Verfahren für eine flächendeckende Überwachung von Standardprozesspumpen entwickelt und prototypisch an 100 Pumpen in einem produzierenden Betrieb der chemischen Industrie umgesetzt.

graph. Darst.

Kreiselpumpen sind in Produktions- und Prozessanlagen der Industrie wichtige Anlagenkomponenten, deren unplanmäßiger Stillstand erhebliche Kosten verursacht. Für einen kostenoptimalen Betrieb ist die Zuverlässigkeit dieser oft prozesskritischen Komponenten folglich unabdingbar. Eine Zustandsdiagnose und Prognose der Restlebensdauer der Pumpen rückt daher zunehmend in den Fokus der Betreiber.

Um ein Diagnosesystem für Pumpen entwickeln zu können, müssen sowohl die Anforderungen der Anwender als auch die der Produktions- und Instandhaltungsprozesse bekannt sein. Zudem müssen ausfallkritische Bauteile und Ausfallursachen identifiziert werden. Dieses Herauszufinden und daraus eine praxistaugliche Zustandsdiagnose abzuleiten, machte sich das Verbundprojekt ReMain zur Aufgabe.

Die Instandhaltung von Pumpen wird heute vorwiegend ausfall- und zeitbasiert durchgeführt. Diese Strategien erzielen jedoch häufig nicht die gewünschte Verfügbarkeit, können nicht alle ungeplanten Stillstände vermeiden und erhöhen die Kosten durch redundante Ressourcen. Auf längere Sicht können die Anforderungen an die Instandhaltung nur durch einen zustandsbasierten, vorausschauenden Ansatz erfüllt werden, der auf ausfallkritische Bauteile und Ausfallursachen einer Pumpe abgestimmt werden muss. Eine praxistaugliche und kostengünstige Zustandsdiagnose der Pumpen und die Ableitung restlebensdauerbezogener Betriebs- und Instandhaltungsstrategien rücken daher zunehmend in den Interessenbereich der Betreiber und Instandhalter. Das Forschungsprojekt ReMain versucht, eine solche Lösung zu entwickeln.

Pumpen sind wichtige Anlagenkomponenten, deren ungeplanter Stillstand erhebliche Kosten verursacht. Um bei Ausfall einer Pumpe dem Stillstand der gesamten Anlage vorzubeugen werden Redundanzen vorgesehen, die entsprechenden Mehraufwand bedeuten. Pumpenbetreiber und -instandhalter praktizieren Strategien der ausfall- und zeitbasierten Instandhaltung, da bisher keine geeignetere Strategie praxistauglich realisierbar ist. Diese erzielen häufig jedoch nicht die maximale Verfügbarkeit, bezogen auf ungeplante Stillstände und den wirtschaftlich optimierten Einsatz von Ressourcen. Auf längere Sicht können die Anforderungen an die Instandhaltung nur durch einen zustandsabhängigen, vorausschauenden Ansatz erfüllt werden, der auf die wesentlichen ausfallkritischen Bauteile und Ausfallursachen abgestimmt werden muss.

Ill., graph. Darst.

U ovom radu je uzvršena hidrodinamička analiza vodovodne mreže grada Velika Gorica. Korišten je hidrodinamički model stacionarnog nestlačivog strujanja, koji je numerički rješavan Hardy-Cross metodom uz upotrebu računala. Nakon izvršenog proračunavanja mreže analizirao se radi pumpi u vodocrpilištu koje opstrbljuje Veliku Goricu vodom. Radi bolje iskoristivosti provela se optimalizacija rada pumpi.

U završnom radu je izvršena optimizacija rada vodovodne mreže grada Zadra. Kako bi se proračun mogao provesti potrebno je bilo uvesti neke dodatne pretpostavke, odnosno definirati hidrodinamički model jednodimenzijskog izotermičkog nestlačivog stacionarnog strujanja fluida. Za proračun je primijenjena metoda Hardy Crossa. Analiziranjem vodovodne mreže u 2h ujutro otkriveni su stanoviti gubitci vode. U svrhu ublažavanja stanja, ugrađeni su regulacijski ventili kojima smo znatno ograničili curenje vode izvan cjevovoda u okoliš. Nažalost, ušteda električne energije nije ostvarena (štoviše, potrošnja električne energije kod jedne pumpe neznatno je porasla).

U radu je prikazan značaj projekta «Eko Kaštelanski zaljev» za smanjenje zagađenja mora i opisani su dijelovi sustava CUPOV Divulje. Dat je pregled temeljnih smjernica za dimenzioniranje i izbor pumpi otpadne vode i cjevovoda. Izvršen je hidraulički proračun pumpnog sustava Divulje- Čiovo. Opisan je utjecaj nestacionarnosti strujanja na rad sustava. Prikazane su posebnosti izgradnje podmorskog cjevovoda.

Ill., graph. Darst.

Das Forschungsvorhaben zielte darauf ab, den Einfluß unterschiedlicher Korrosionsparameter auf die Korrosionsschwingfestigkeit von mit 13 bzw. 17% Chrom legierten Stahlgußwerkstoffen für Wasserkraftanlagen im Bereich hoher Schwingspiele (10(exp 6) < N < 10(exp 8)) zu erfassen. Dabei wurde der gesamte Bereich der für derartige Anlagen in Frage kommenden Arbeitsmedien in einer gezielt ausgewählten Abstufung untersucht: Leitungswasser mit 28 ppm Chloriden, 10 mMol NaCl bzw. 1% NaCl und für den höherlegierten Werkstoff zusätzlich künstliches Meerwasser mit und ohne kathodischen Schutz. Darüber hinaus wurde der Einfluß von fliehkraftbedingten Mittelspannungen erfaßt. Die erhaltenen Ergebnisse zum Abfall der Korrosionsschwingfestigkeit von Stahlguß in Abhängigkeit des Korrosionsmediums, der Mittelspannung und Schwingspielzahl ermöglichen eine zutreffende Werkstoffauswahl in Abstimmung mit dem jeweiligen, für die Wasserkraftanlage vorgegebenen Arbeitsmedium und leisten damit einen Beitrag zur Bemessung sowie Verbesserung der Verfügbarkeit und Ausfallsicherheit derartiger Energieerzeugungsanlagen.

Im Rahmen der vorliegenden Arbeit wurden sowohl neuartige polymere Hochleistungsverbundwerkstoffe als auch unterschiedliche Modellprüfmethoden zur Nachbildung abrasiver Verschleißbedingungen entwickelt. Ausgangspunkt für diese Themenstellung war, Verbundwerkstoffe als alternative Gleitlagermaterialien in hermetisch dichten Pumpen für aggressive und abrasive Medien einzusetzen. Stand der Technik sind hierbei keramische Gleitlager, insbesondere aus monolithischem Siliziumkarbid. Das Ziel war somit zu untersuchen, ob Polymerwerkstoffe derart modifiziert werden können, dass ein vergleichbares Verschleißverhalten erreicht wird. Auf der Basis von Epoxidharz wurde die elementare Werkstoffentwicklung, durch Variation von Füll- und Verstärkungsstoffe, hinsichtlich Art, Größe und Menge, durchgeführt. Die Formulierung mit den in Summe günstigsten Eigenschaften wurde anschließend auf einen weiteren Duroplasten (Vinylester) und einen Thermoplasten (Etylentetrafluorethylen) übertragen. Auf diese Weise konnte gezeigt werden, dass das Verschleißverhalten bei hochgefüllten Systemen maßgeblich von den Füll- und Verstärkungsstoffen geprägt wird und durch die Übertragung der Formulierung ähnliche Verschleißraten erzielt werden. Weiterhin wurde der Einfluss der Aushärtungstemperatur, und somit des Herstellungsprozesses, auf die Werkstoffeigenschaften dargestellt. Durch eine weiterführende Werkstoffmodifikation, den Einsatz multimodaler Korngrößenverteilungen, war es zudem möglich die tribologischen Eigenschaften nochmals zu verbessern. Der Vergleich der Werkstoffeigenschaften erfolgte mittels mechanischer und tribologischer Prüfungen. Letztere waren jedoch nur bedingt anwendbar, um einen Vergleich zwischen den neu entwickelten Hochleistungsverbundwerkstoffen und dem Referenzwerkstoff Siliziumkarbid zu ermöglichen. Aus diesem Grunde wurde ein spezieller Medienprüfstand konstruiert und aufgebaut, um verschiedenste abrasive Prüfbedingungen, ob geschmiert oder ungeschmiert, simulieren zu können. Mit Hilfe abrasiver Gegenkörper war es möglich die Testzeit von 20 Stunden auf 60 Sekunden zu verkürzen. Die anschließende Validierung der Ergebnisse ergab eine gute Übereinstimmung. Zur Ableitung allgemein gültiger Aussagen wurden die Ergebnisse anhand dreier Verschleißmodelle für abrasive Bedingungen (Archard, Budinski, Ratner et al) überprüft. Dabei erwies sich jedoch keines der Modell als passend, um alle experimentellen Werte abbilden zu können. Dennoch lies sich erkennen, dass das Deformationsverhalten bei abrasiven Verschleißvorgängen eine bedeutende Rolle spielt. Deshalb wurde das Deformationsverhalten von drei exemplarischen Verbundwerkstoffen bei einer dynamischen Mikrohärteprüfung mittels der Finiten Elemente Methode (FEM) simuliert. Es zeigte sich, dass zum einen die Berechnungen und die experimentellen Ergebnisse sehr gut übereinstimmen. Zum anderen sind die entwickelten FEM Modelle sehr gut geeignet, um das Verschleißverhalten zu erklären. In the frame of this dissertation new polymeric high performance composite materials were developed as well as different testing methods to replicate abrasive wear conditions. Initial point fort his theme was to establish composite materials as alternative slide bearing material in hermetical closed pumps for aggressive and abrasive media. State-of-art for this application are slide bearings made of ceramic materials, especially monolithic silicon carbide. Thus, the aim of this work was to investigate whether polymeric materials could be modified in such a manner that they offer comparable wear behaviour. On the basis of epoxy resin the fundamental material development was conducted by varying fillers and reinforcing components regarding type, size and quantity. Afterwards the formulation with well-balanced properties was transferred to another thermosetting material (Vinylester) and a thermoplastic (Etylentetrafluorethylen). This way it was possible to demonstrate that the wear behaviour of highly filled systems is significantly influenced by the incorporated fillers and reinforcing components and by transferring the formulation similar wear rates can be obtained. Furthermore, the effect of the curing temperature and thus the manufacturing process on the material properties was described. Through the addition of multimodal particle size distributions to the composite materials the tribological behaviour could be enhanced again. The examination of the material properties was realised by mechanical and tribological tests. However, the latter were conditionally useful to compare the newly developed high performance composite materials with the reference material, monolithic silicon carbide. Out of this reason a special media test rig was designed and built up to be able to simulate lubricated and unlubricated abrasive wear conditions. By utilising abrasive counterparts it was possible to cut down the testing time from 20 hours to 60 seconds. The following validation of the results revealed a good agreement. To draw universally valid conclusions the experimental results were reviewed with three wear models, suitable for abrasive conditions (Archard, Budinski, Ratner et al). Thereby, none of the models proved to be adequate to reproduce all experimental values. Nevertheless it could be identified that the deformation behaviour plays an important role during abrasive wear processes. Hence the deformation behaviour of three exemplary composite materials was simulated with the finite element method (FEM) while a dynamic micro hardness measurement. It was found that the calculated and the experimental data fitted in good agreement. Furthermore, the developed FEM models suit very well for explaining the wear behaviour.

Im Rahmen der vorliegenden Arbeit wurden sowohl neuartige polymere Hochleistungsverbundwerkstoffe als auch unterschiedliche Modellprüfmethoden zur Nachbildung abrasiver Verschleißbedingungen entwickelt. Ausgangspunkt für diese Themenstellung war, Verbundwerkstoffe als alternative Gleitlagermaterialien in hermetisch dichten Pumpen für aggressive und abrasive Medien einzusetzen. Stand der Technik sind hierbei keramische Gleitlager, insbesondere aus monolithischem Siliziumkarbid. Das Ziel war somit zu untersuchen, ob Polymerwerkstoffe derart modifiziert werden können, dass ein vergleichbares Verschleißverhalten erreicht wird. Auf der Basis von Epoxidharz wurde die elementare Werkstoffentwicklung, durch Variation von Füll- und Verstärkungsstoffe, hinsichtlich Art, Größe und Menge, durchgeführt. Die Formulierung mit den in Summe günstigsten Eigenschaften wurde anschließend auf einen weiteren Duroplasten (Vinylester) und einen Thermoplasten (Etylentetrafluorethylen) übertragen. Auf diese Weise konnte gezeigt werden, dass das Verschleißverhalten bei hochgefüllten Systemen maßgeblich von den Füll- und Verstärkungsstoffen geprägt wird und durch die Übertragung der Formulierung ähnliche Verschleißraten erzielt werden. Weiterhin wurde der Einfluss der Aushärtungstemperatur, und somit des Herstellungsprozesses, auf die Werkstoffeigenschaften dargestellt. Durch eine weiterführende Werkstoffmodifikation, den Einsatz multimodaler Korngrößenverteilungen, war es zudem möglich die tribologischen Eigenschaften nochmals zu verbessern. Der Vergleich der Werkstoffeigenschaften erfolgte mittels mechanischer und tribologischer Prüfungen. Letztere waren jedoch nur bedingt anwendbar, um einen Vergleich zwischen den neu entwickelten Hochleistungsverbundwerkstoffen und dem Referenzwerkstoff Siliziumkarbid zu ermöglichen. Aus diesem Grunde wurde ein spezieller Medienprüfstand konstruiert und aufgebaut, um verschiedenste abrasive Prüfbedingungen, ob geschmiert oder ungeschmiert, simulieren zu können. Mit Hilfe abrasiver Gegenkörper war es möglich die Testzeit von 20 Stunden auf 60 Sekunden zu verkürzen. Die anschließende Validierung der Ergebnisse ergab eine gute Übereinstimmung. Zur Ableitung allgemein gültiger Aussagen wurden die Ergebnisse anhand dreier Verschleißmodelle für abrasive Bedingungen (Archard, Budinski, Ratner et al) überprüft. Dabei erwies sich jedoch keines der Modell als passend, um alle experimentellen Werte abbilden zu können. Dennoch lies sich erkennen, dass das Deformationsverhalten bei abrasiven Verschleißvorgängen eine bedeutende Rolle spielt. Deshalb wurde das Deformationsverhalten von drei exemplarischen Verbundwerkstoffen bei einer dynamischen Mikrohärteprüfung mittels der Finiten Elemente Methode (FEM) simuliert. Es zeigte sich, dass zum einen die Berechnungen und die experimentellen Ergebnisse sehr gut übereinstimmen. Zum anderen sind die entwickelten FEM Modelle sehr gut geeignet, um das Verschleißverhalten zu erklären. In the frame of this dissertation new polymeric high performance composite materials were developed as well as different testing methods to replicate abrasive wear conditions. Initial point fort his theme was to establish composite materials as alternative slide bearing material in hermetical closed pumps for aggressive and abrasive media. State-of-art for this application are slide bearings made of ceramic materials, especially monolithic silicon carbide. Thus, the aim of this work was to investigate whether polymeric materials could be modified in such a manner that they offer comparable wear behaviour. On the basis of epoxy resin the fundamental material development was conducted by varying fillers and reinforcing components regarding type, size and quantity. Afterwards the formulation with well-balanced properties was transferred to another thermosetting material (Vinylester) and a thermoplastic (Etylentetrafluorethylen). This way it was possible to demonstrate that the wear behaviour of highly filled systems is significantly influenced by the incorporated fillers and reinforcing components and by transferring the formulation similar wear rates can be obtained. Furthermore, the effect of the curing temperature and thus the manufacturing process on the material properties was described. Through the addition of multimodal particle size distributions to the composite materials the tribological behaviour could be enhanced again. The examination of the material properties was realised by mechanical and tribological tests. However, the latter were conditionally useful to compare the newly developed high performance composite materials with the reference material, monolithic silicon carbide. Out of this reason a special media test rig was designed and built up to be able to simulate lubricated and unlubricated abrasive wear conditions. By utilising abrasive counterparts it was possible to cut down the testing time from 20 hours to 60 seconds. The following validation of the results revealed a good agreement. To draw universally valid conclusions the experimental results were reviewed with three wear models, suitable for abrasive conditions (Archard, Budinski, Ratner et al). Thereby, none of the models proved to be adequate to reproduce all experimental values. Nevertheless it could be identified that the deformation behaviour plays an important role during abrasive wear processes. Hence the deformation behaviour of three exemplary composite materials was simulated with the finite element method (FEM) while a dynamic micro hardness measurement. It was found that the calculated and the experimental data fitted in good agreement. Furthermore, the developed FEM models suit very well for explaining the wear behaviour.

Keramische Werkstoffe aus Siliciumcarbid werden heute standardmäßig für Gleitkomponenten in Pumpen für beliebige Medien eingesetzt. Entscheidende Vorteile dieser Keramik gegenüber anderen Werkstoffen sind die hohe Verschleißbeständigkeit auch in chemisch aggressiver Umgebung bei gleichzeitig niedrigen Reibwerten in wässriger Umgebung.

Ill., graph. Darst.