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V današnjem svetu je električna energija neprecenljive vrednosti. Vendar pa ni dvoma, da se obdobje uporabe fosilnih goriv končuje, saj svetovne zaloge počasi pojenjajo. Temu primerno bomo prisiljeni posegati po obnovljivih virih, ključen del le-teh predstavlja tudi voda. Hidroenergija v svetu pomeni veliko prednost in je pomemben energetski vir. Slovenija ima zelo bogato tradicijo na področju gradnje hidroelektrarn, primer je hidroelektrarna Fala, ki je stara več kot sto let. Gradnje teh objektov so na našem ozemlju potekale že pred prvo svetovno vojno, v obdobju med obema vojnama in tudi po drugi svetovni vojni. Od takrat do danes se sredstva preusmerja v obnovo in nadgradnjo že obstoječih objektov. S tem sta se povečali tako moč kot tudi količina proizvodnje električne energije. Izrednega pomena pri vsem tem je, da skoraj vsa dela izvajajo slovenska podjetja. Kot že omenjeno, so hidroelektrarne zelo pomemben vir električne energije tako po svetu kot v Sloveniji. Kljub temu mnoge študije in strokovne ustanove poročajo o tem, da je pri nas še vedno izkoriščena le približno polovica vsega vodnega potenciala. Neizkoriščeni ostajajo mnogi potoki in manjše reke, ki bi lahko predstavljali velik doprinos. Slovenska zgodovina je lep pokazatelj tega, kako izkoristiti omenjena vodna telesa, saj je bilo postavljenih skoraj pet tisoč pregrad, ki so služile kot mlini, žage in kovačije. Te objekte bi se dalo obnoviti in namesto njih zgraditi mikro hidroelektrarne. Največji problem predstavljajo zamudni postopki umeščanja mikro hidroelektrarne v prostor. Za objekt, ki se v povprečju postavi v enem letu, se od pobude do začetka gradnje porabi kar deset let. V primerjavi s Slovenijo, v sosednji Avstriji tak postopek traja le pol leta. Slovenija je v evropskem sporazumu zavezana, da do leta 2030 doseže kar 27-odstotni delež obnovljivih virov energije v skupni rabi bruto končne energije. Dejstvo je, da se poraba električne energije povečuje, svet pa stremi k obnovljivim virom energije. Prej kot slej bomo primorani sprejeti strateški energetski dokument in začeti sklepati kompromise, da dosežemo zadane cilje. Today, electricity is considered priceless. However, the era of fossil fuels is undoubtedly ending as the resources are running empty and with that, people will be forced to find new, renewable sources - a key source being water. Hydro energy is a very important energy source and a huge advantage to the world's power supply. Slovenia itself has a very rich tradition of building hydroelectric power plants. A good example being hydroelectric power plant Fala that has been around for over a hundred years. Building those facilities on Slovenian ground has been in progress since before, during, and after both world wars. Since then the resources have been diverted towards renovations and upgrades on already standing facilities. With that, the amount and the quality of electric power have increased. An important fact is that almost all of the work done has come from Slovenian contractors. As abovementioned, hydroelectric power plants are one of the most important power sources in the world and in Slovenia as well. That aside, many studies report a very low use of the water potential in Slovenia, estimating it to only a half. There are many unused creeks and smaller rivers that could represent a large contribution. Slovenian history is a beautiful representation of the way how to exploit bodies of water, since there had been almost five thousand dams used for mills, saws, and forgeries. These bodies of water could be restored and used as micro hydroelectric power plants. The largest problem is the time-consuming process of placing these power plants. The construction of a micro hydroelectric plant takes about a year. It takes ten years to get from the initiative to the beginning of the building process. Comparing Slovenia to Austria where the same process takes only half a year. Slovenia has a contract with the European Union and is, therefore, obliged to reach 27 per cent of renewable energy in final gross energy consumption. In addition, it is a fact that power use is increasing. The world strives for renewable power sources and sooner rather than later people will be forced to strategize and compromise to achieve their goals.

Da odgovorimo na potrebo po novi turbini nižjih specifičnih hitrosti, ki bo ohranjala prednosti Saxo turbin, smo izdelali novo enojno regulirano vertikalno cevno turbino, ki z diagonalnim gonilnikom omogoča nižjo specifično hitrost. Zaradi stroškov in časa potrebnega za izvajanje eksperimentalnega preizkušanja vodnih turbin, smo izvedli numerične simulacije za vrednotenje delovanja nove turbine. Na podlagi računalniške dinamike tekočin, so bile izvedene simulacije za različne obratovalne točke nove turbine. Pri izvajanju simulacij smo upoštevali predpostavke za nestisljiv enofazni tok. Predstavljene in razložene so uporabljene vodilne enačbe, z izbranim turbulentnim modelom SST. Iz simuliranih obratovalnih točk, je bil modeliran školjčni diagram, ki ima v primerjavi s Saxo turbino zaradi enojne regulacije manjše delovno območje optimalnega izkoristka. Nova konfiguracija doseže cilj nižjih specifičnih hitrosti, na področju med Francisovimi in diagonalnimi tipi turbin. S podrobnejšo analizo treh obratovalnih točk, smo predstavili kavitacijske, in tokovne razmere po turbini. Na področju delnih obremenitev, pride do pojava medlopatične vrtinčne kavitacije in opletajočega kavitacijskega vrtinca v sesalni cevi. Opazovani pojavi so primerljivi s tistimi v Francisovih turbinah. To answer the need for a new water turbine, with lower specific speeds, that would maintain all of the advantages of Saxo turbines. We designed a new single regulated vertical tubular turbine, with a diagonal runner, that enables lower specific speeds. Rather than performing expensive and time consuming experimental tests for water turbines, we used numerical simulations for evaluation of working parameters for the new turbine. Computational fluid dynamics were used to simulate different operating points. With the simulations, we have assumed incompressible single-phase flow. We presented and explained all the used leading equations, with the SST turbulence model. From the simulated operating points, we modelled the hill diagram for the new turbine, which has a smaller area of optimal performance compared to Saxo turbines. The new configuration acquires lower specific speeds between Francis and diagonal type turbines. With a more extensive analyzation, we observed three separate operating points and present cavitation and flow conditions in the turbine. In part load operation, we observed the emergence of inter-blade cavitating vortices and vortex rope in draft tube. The observed conditions are similar to those in Francis type turbines.

V zaključni nalogi smo obravnavali karakteristike in postopek določanja karakteristik aksialne vodne turbine. Opazovali smo, kako se izhodna moč in izkoristek turbine spreminjata pri različnih obratovalnih pogojih. Meritve smo izvedli na modelnem preizkuševališču FM3SU, na katerem je bila nameščena modelna različica aksialne vodne turbine. Med preizkusom smo merili volumenski tok in tlak vode pred vstopom v turbino, vrtilno frekvenco gonilnika turbine ter zaviralno silo. Na podlagi meritev smo zasnovali diagrame karakteristik in školjčni diagram aksialne vodne turbine. Ugotovili smo, da se izhodna moč in izkoristek povečujeta z večanjem volumenskega toka vode in da največji izkoristek dosežemo pri polovični obremenitvi sistema. Nazadnje smo z analizo školjčnega diagrama uspešno določili območje optimalnega delovanja preizkušene turbine. In the thesis we discussed the characteristics and the process of obtaining the characteristics of an axial water turbine. We observed the power and the efficiency of the water turbine changing with the change of operating conditions. All the measurements were obtained on model testbed FM3SU with axial water turbine. During the experiment we measured water volume flow and water inlet pressure before turbine, rotational speed of the turbine wheel and the breaking force. Based on the measurements and calculations characteristics diagrams and hill chart of an axial turbine were designed. We found out that the power and the efficiency of the axial water turbine is higher, with the increase of the water volume flow furthermore we concluded that the maximum efficiency was reached, when the turbine was burdened with the half of breaking load. Finally, with the analysis of the hill chart, we determined the optimal work conditions of the tested axial water turbine.

The vibration behaviour of an emergency gate situated on a horizontal-shaft Kaplan turbine is studied. The analysis and transfer of the dynamic movements of the gate are quite complex. In particular the behaviour is examined of the emergency gate for the case when the power unit is disconnected from the system or there is a breakdown of the guide vane system at the moment when the maximal head and capacity are achieved. Experimental-numerical methods both in the time domain and in the frequency are employed. Natural vibrations characterize a first zone, corresponding to relatively small gate openings. As the gate opening increases, the vibration behaviour of the gate becomes increasingly dependent on the swirl pulsations in the draft tube of the turbine. Finally, the data transfer from the model to the prototype by use of the dinamic similitude law is discussed.

V diplomskem delu smo predstavili ključne elemente male hidroelektrarne in njihova delovanja. Za predstavitev rezultatov meritev smo uporabili asinhronski generator, ki je za gradnjo MHE primeren. Izbrani motor smo preračunali s pomočjo programskega paketa emLook, ter predstavili primerjavo rezultatov z nazivnimi vrednostmi. V nadaljevanju smo se osredotočili na meritev obremenitev asinhronskega generatorja, ter primerjavo rezultatov z obremenitvijo s kompenzacijo. Izmerili smo asinhronski generator v otočnem obratovanju pri različnih kapacitivnostih, ki smo jih spreminjali v okolici nazivne vrednosti kondenzatorjev. Pri tej meritev smo še opravili meritev prostega teka. Kot zadnjo meritev smo predstavili izklop pogona in bremena na omrežju. Below we present the key elements of the small hydroelectric power plants and their operation. For the presentation of the results of the measurements we used asynchronous generator, which is for the construction of SHP most suitable. Selected engine was calculated using a software package emLook, and a comparison of the results with the nominal values. Below we focus on the measurement of load induction generator, and compare the results with a load with compensation. We measured the induction generator in an island mode with different capacitances, we change up and down from the selected or calculated value capacitors. In this measurement, we have conducted measurements idling. As a final measurements are presented off actuator and the load on the network.

V diplomskem delu so predstavljene osnove energije vode in opisane glavne vrste hidroelektrarn ter vodnih turbin. Delovanje hidroelektrarn je v predstavljeno v funkcijski strukturi, kjer smo se osredotočili na akumulacijske hidroelektrarne. Akumulacijskim hidroelektrarnam so določeni fizikalni principi delovanja, njihovi vplivni parametri in njihove možnosti za optimiranje. Opisani so tudi sistemi, ki delujejo na podlagi enakih fizikalnih principov kot akumulacijske hidroelektrarne, a se uporabljajo za druge namene. In this diploma basics of water energy are introduced and main types of hydro power stations and water turbines are also described. Hydro power stations activity is introduced in functional structure, where we focused on accumulative hydro power stations. Physical principals and their influential parameters as also their optimization abilities are defined for accumulative hydro power stations. Some systems, which work on the same physical principals as accumulative hydro power stations, but are used for other purposes, are also described.

V diplomski nalogi smo predstavili izkoriščanje hidro-energije z majhnimi kinetičnimi turbinami, opravili smo preračune moči turbin in določali njihov izkoristek. Predstavljeni so možni tipi turbin za postavitev v rečno korito. Določili smo ekonomsko analizo projekta. The graduation thesis present hydro-power exploitation with low-kinetic turbines, we made calculations of power turbines and determine their efficiency. Presented are the possible types of turbines for installation in the riverbed. We determined the economic analysis of the project.

V diplomskem delu je predstavljeno pridobivanje električne energije iz vodne energije. Opisane so Peltonova, Francisova in Kaplanova vodna turbina, ki se v elektrarnah največkrat uporabljajo ter razlika med pretočnim in akumulacijskim hidroelektrarnam. Predstavljene so hidroelektrarne v Sloveniji na rekah Drava, Sava in Mura. Izračunana je časovna razporeditev kinetičnega hidropotenciala reke Mure glede na njen dnevni pretok. Opisani sta dve metodi pouka projektni pouk oz. naloga in eksperiment. V 7. razredu pri tehniki in tehnologiji se lahko z učenci izvaja ta projektna naloga. Za informiranje učencev na temo hidroelektrarne, je pripravljena predstavitev v PowerPointu. Izdelan je tudi tehnološki list in delavniške risbe. The thesis presents the generation of electricity from hydropower. I have described Pelton's, Francis's and Kaplan's water turbine, which are most often used in power plants, and also the difference between hydroelectric power plants and storage hydropower plants. There are presented hydropower plants on Slovenian rivers Drava, Sava and Mura and I have also calculated the timing of kinectic hydro potential of the river Mura in termes of its daily circulation. Two methods of teaching are described project work and task with an experiment. In 7th grade in the technology course students can practice the project work. In order to inform students about hydroelectric power I have prepared the PowerPoint presentation. Technology journal and mechanical drawings are also designed.

Magistrska naloga, mala hidroelektrarna na reki Sopoti, je izdelana z namenom in ciljem ugotoviti smiselnost koriščenja tega vodnega vira. Izbira in obdelava te teme me je pritegnila iz tega razloga, ker je tu nekoč že obratovala mala hidroelektrarna, ki pa so jo približno pred dvajsetimi leti ustavili. V nalogi sem zajel in predstavil zakonodajo in postopke, ki so potrebni pri izvedbi takega projekta. Na splošno je, moja ugotovitev, da so v naši državi ti administrativni postopki preveč zahtevni, še bolj pa komplicirano zastavljeni. Na koncu naloge sem v ekonomski analizi prikazal in dokazal, z določenimi metodami , da je smiselno postaviti tako elektrarno in jo koristiti kot stalen obnovljiv vir. The master's thesis »The small hydro plant on the riverSopota« (Mala hidroelektrarna na reki Sopoti) is written with an aim to asses the benefits of employing the previously mentioned hydro plant as anenergy source. The theme and its analysis intrigued me due to the fact that thepower plant used to be operational but closed its doors nearly twenty years ago. The thesis comprises of the presentation of the legislation and the legislativeprocedures needed for the execution of such a project. I have come to theconclusion that these administrative procedures are too overwhelming in ourcountry and moreover, complicated. In the economic analysis at the end of the thesis I have demonstrated and proventhat the setting up and employment of such a hydro plant as a renewable energysource is reasonable.

Simulacija strujanja u privodu voden turbine HE Zeleni vir s ciljem izmjene gemetrije privoda radi smanjenja gubitaka.

Hidrodinamična tesnilka gredi je obvezen del opreme vsake vodne turbine. Njena naloga je preprečiti vdor rečne vode v notranjost postrojenja med vrtečimi in mirujočimi se deli stroja na način, da z ustrezno konstrukcijo njenega mehanskega dela ter kontroliranim dovodom hladilne tekočine ustvarimo razmere za tesnjenje. Pogoji za ustrezno mazanje drsne površine so odvisni tako od hidroloških parametrov vodne turbine kot tudi od samega oblikovanja tesnilnega vložka. Pri diplomskem delu sem se usmeril na raziskavo: - kako konstrukcijsko oblikovati tesnilni vložek, da bo zagotovljen pogoj enakomernosti pritiska na drsno površino - kako doseči enakomernost in neprekinjenost dotoka ustrezne hladilne vode na drsno površino - kako se tlačne razmere na drsni površini tesnilke spreminjajo v prehodnih obratovalnih režimih vodne turbine (meritve na objektu) Cilj tega diplomskega dela je na osnovi analize rezultatov praktičnih meritev in teoretičnih izračunov opisati bistvene parametre aksialne hidrodinamične tesnilke v stacionarnih in ključnih prehodnih režimih obratovanja ter na osnovi teh določiti obliko ustreznega tesnilnega vložka. Hydrodynamic shaft seal is a mandatory part of every water turbine. It is meant to prevent breach of river water in between rotated and stationary turbine parts by means of creating sealing conditions by implementation of adequate mechanical parts construction and controlled cooling water quantity. Conditions of adequate lubrication of sliding surface are in correlation with hydrologic parameters of water turbine and sealing insert design. My graduation work concentrates on research of: - how the sealing insert shall be designed in order to fulfill the requirement of uniform pressure on the sliding surface, - how to reach uniform and continued inflow of adequate cooling water to sliding surface, - how the pressure conditions on the sliding surface are being changed during transitions in turbine operation (site measurements) The goal of this graduation work is to describe essential parameters of axial hydrodynamic seal during stationary and key transitional regimes of operation on the basis of the analysis of practical measurements results and theoretical calculations results, and to design adequate sealing insert form accordingly.

Idejna študija male hidroelektrarne Malenščica je izdelana s ciljem ugotoviti smiselnost koriščenja danega vodotoka. Podane so možne rešitve in primerjava danih rešitev. Izdelana je tudi groba ocena stroškov ter ocena časa povrnitve stroškov investicije. Na osnovi preračunov je izbrana najboljša rešitev. A case study of a small hydroelectric power station Malenščica has been done with a goal to ensure reasonableness of using the given water current. There have been possible solutions and a comparison of the given solutions given. A rough estimation has been done and the estimation of repayment time of the investment. According to the calculus, the best solution has been chosen.

Analiza strujanja u turbinama HE Jajce II. Analiza rada kod nadvišenja brane.

Članak opisuje metodu proračuna karakteristika vodnih turbina pomoću spline - interpolacije funkcije dviju varijabli. Problem se susreće pri interpolaciji staatičkih karakteristika vodnih turbina s dvostruko-regulirajućim lopaticama statora i radnog kola (rotora). Predložena je i modifikacija tog algoritma u slučaju propelernih (Kaplan i cijevnih) radnih kola. Kompjutorski programi izrađeni na predloženim rješenjima su jednostavni, zadovoljavajuće brzine i točnosti i malih zahtjeva za memorijskim kapacitetom računala. Predložena metoda interpolacije može biti od pomoći u kompjutorskim simulacijama prijelaznih pojava u hidroenergetskim postrojenjima s vodnom turbinom ili pumpom.