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Eligibility analysis of projects to increase energy efficiency of existing multi-apartment buildings by developing a conceptual model
No full textV magistrskem delu je analizirana upravičenost izvedbe projektov večanja energetske učinkovitosti večstanovanjskih stavb. V prvem delu magistrskega dela je predstavljen teoretičen del, vezan na projekte, nato je pojasnjen pojem energetske učinkovitosti stavb in predstavljeni so trenutni ukrepi in spodbude za dosego strateških ciljev države na tem področju. Pojasnjen je vpliv in naloge upravnika v večstanovanjskih stavbah. V praktičnem delu so na podlagi že izvedenih projektov na področju energetske učinkovitosti stavb analizirane tehnične in ekonomske posledice izvedbe takšnih projektov. Na podlagi analize je razvit konceptualni model, na podlagi katerega se bodo lastniki večstanovanjskih stavb in upravniki lažje odločili, katere projekte izvesti, ob kakšnih pogojih in v kakšnem zaporedju.This master thesis analyses the eligibility of energy efficiency increase projects in multi-apartment buildings. The first section presents the theoretical part relating to the projects, followed by an explanation of the concept of energy-efficient buildings, including the current measures and initiatives to achieve the strategic objectives of the government in the field, alongside the description of the role and the tasks of a building manager in multi-apartment buildings. The practical section contains the analysis of technical and economic consequences of the implementation of said projects, based on already implemented projects in buildings. According to the results, a conceptual model was developed that should help owners and building managers of multi-apartment buildings determine which projects to implement, under what conditions, and in which order
Construction of scrap cutting machine
No full textV tem magistrskem delu je predstavljeno konstruiranje sekalne naprave za aluminijaste profile. Problem naloge predstavlja potreba po novem stroju, ki je namenjen razrezu odpadnih aluminijastih profilov daljših dimenzij (5-6 m) na krajše kose (do 30 cm). V delu je bolj ali manj podrobno zajet celoten proces konstruiranja in tako obsega naslednje teme: opis problema, opis in izvedba štirih korakov konstruiranja (načrtovanje, koncipiranje, snovanje in razdelava), področje tehnične zakonodaje, ter varnosti in skladnosti stroja, področje vzdrževanja, okvirno stroškovno analizo, na koncu pa so predstavljeni še doseženi cilji in predlogi za nadaljnje delo.This master\u27s thesis work presents how scrap cutting machine are designed. The problem of the task is the need for a new machine, which is intended for cutting waste aluminum profiles of longer dimensions (5-6 m) into shorter pieces (up to 30 cm). The work covers the entire design process in more or less detail and thus includes the following contents: description of the problem, description and implementation of the four design steps, the area of technical regulation and machine safety, the area of maintenance and a rough cost analysis. At the end, the achieved goals are presented, followed by suggestions for further work
Analysis of influential parameters on the squezzing effect of washing machines
No full textOžemanje perila je ena izmed ključnih faz pri pranju perila s pralnim strojem. V magistrskem delu smo se osredotočili na analizo potencialno vplivnih parametrov na ožemalni učinek. Raziskava je razdeljena na dva glavna sklopa. Prvi sklop zajema pregled obstoječih tehnologij in teoretične osnove. Predstavljena je analiza stanja tehnike, ki se navezuje na delovanje pralnega stroja. Opisane so sestava in delovanje pralnega stroja, faza ožemanja perila in uporabljene statistične enačbe pri analizi rezultatov. Drugi sklop obravnava raziskovalne metode in rezultate. V tem sklopu so predstavljeni postopki in oprema za pridobivanje podatkov ter sami rezultati, ki prikazujejo vpliv posameznih parametrov na ožemalni učinek. V diskusiji so podrobneje analizirani potencialno vplivni parametri, kot so čas ožemanja, končna vrtilna hitrost ožemanja, temperatura vode in neuravnotežena masa perila v bobnu pralnega stroja med ožemanjem.Spin-drying is one of the key phases in the washing process using a washing machine. This master\u27s thesis focuses on the analysis of influential parameters affecting the squeezing effect. The research is divided into two main parts. The first part covers an overview of existing technologies and the theoretical foundations. An analysis of the state of the art related to the operation of washing machines is presented. The composition and operation of the washing machine, the spin-drying phase, and the statistical equations used in the analysis of the results are described. The second part addresses research methods and results. This section presents the procedures and equipment used for data collection, as well as the results themselves, which show the impact of individual parameters on the squeezing effect. The discussion provides a detailed analysis of influential parameters, such as time, spin speed, water temperature, and unbalanced load in the washing machine drum during spin-drying
Structural, electrical and safety configuration of the robotic palletiser
No full textMagistrska naloga se osredotoča na razvoj in implementacijo naprednega robotskega paletizatorja, ki združuje ključne aspekte konstrukcije, električne povezave in varnosti. Naloga vključuje podrobno konstruiranje in obremenitvene teste za podstavek robotske roke. Konstruiranje se osredotoča na: čimbolj kompaktno izvedbo, enostaven transport celotnega podstavka, zagotavljanje prostora za krmilnik robotske roke in elektro omarico ter pripravljenost na nadgradnje (dodatna sedma os). V nalogi je izdelan električen načrt celotnega sistema.
Zadnji sklop naloge zajema integracijo varnostnih tehnologij, kot so varnostni laserski skenerji. Poseben poudarek je na skladnosti z varnostnim standardom ISO 15066 in na zagotavljanju varne in učinkovite uporabe v industrijskem okolju ter določanje razdalje varnostnih območij.The master\u27s thesis focuses on the development and implementation of an advanced robotic palletizer, integrating essential aspects of design, electrical connections, and safety. It includes detailed construction and load testing for the robotic arm base, emphasizing compact execution, easy transport, space for the robotic arm\u27s controller, and electrical cabinet, and readiness for upgrades like an additional seventh axis. The thesis also develops a comprehensive electrical plan for the entire system and integrates safety technologies such as safety laser scanners, with a special emphasis on compliance with the ISO 15066 safety standard, ensuring safe and efficient use in industrial environments and determining the distance of safety zones
Development of composite nanofibres based on keratin obtained by hydrothermal process
No full textKeratin, prisoten v živalskih tkivih, kot sta perje in volna, predstavlja velik delež odpadkov iz tekstilne, kmetijske in mesno-predelovalne industrije. Zaradi težnje po zmanjšanju negativnih vplivov na okolje je nujna učinkovita pretvorba teh odpadkov v produkte z dodano vrednostjo. Metode ekstrakcije keratina iz različnih virov se razlikujejo predvsem po kvaliteti dobljenega ekstrakcijskega produkta in po njihovem okoljskem vplivu, pri čemer je glavni izziv uporabiti okolju prijazne metode za ekstrakcijo, ki dajejo keratin, primeren za specifično uporabo. Magistrska naloga se osredotoča na razvoj stabilnih nanovlaken iz keratina, pridobljenega iz odpadnega perja in volne s hidrotermičnim postopkom z uporabo subkritične vode. V ta namen so bile iz liofiliziranih ekstrakcijskih produktov pripravljene predilne raztopine. Zaradi mejnih vrednosti povprečja molskih mas v ekstrakcijskih produktih, smo keratin kombinirali s polietilen oksidom (PEO) v razmerjih 50/50 in 70/30. Za izdelavo nanovlaken je bila uporabljena tehnika brezigelnega elektropredenja, pri čemer smo optimizirali pogoje predenja. Z namenom izboljšanja stabilnosti izpredenih nanovlaken smo uporabili dva postopka zamreženja, in sicer z etilen glikol diglicidil etrom (EGDE) in z pentaeritritol triakrilatom (PETA). Predilnim raztopinam so bile pred predenjem analizirane naslednje lastnosti: prevodnost, viskoznost, pH, površinska napetost, velikost delcev, zeta potencial in koncentracija proteina. Kemično strukturo liofiliziranega keratina in izdelanih nanovlaken smo spremljali z infrardečo spektroskopijo (ATR-FTIR). Vrstična elektronska mikroskopija (SEM) je bila uporabljena za analizo uspešnosti oblikovanja nanovlaken, merjenje kontaktnih kotov pa za analizo hidrofilnosti nanovlaken. Za določanje antioksidativnosti raztopin keratin/PEO in nanovlaken je bila uporabljena metoda ABTS. Izkoristek ekstrakcije keratina iz odpadnega perja in volne je znašal 87,46 % ter 88,33 %. S tehniko SDS-PAGE je bila določena največja koncentracija molskih mas v suspenziji keratina iz perja in iz volne v območju med 4,6 in 9 kDa. Rezultati so pokazali, da je iz liofiliziranih produktov mogoče izdelati nanovlakna, ki vsebujejo relativno velike deleže (tudi do 70 %) keratina v mešanicah s PEO. Nanovlaknom iz mešanic keratin/PEO smo po zamreženju s PETA in z EGDE uspeli identificirati tipične keratinske vrhove s ATR-FTIR, kar jih naredi ključne za uporabo v biomedicinskih aplikacijah. Stopnja antioksidativnosti izdelanih nanovlaken je bila visoka (86,9 % inhibicija) in postopki zamreženja nanjo niso imeli pomembnega vpliva. Z uporabo zamreževalca PETA smo dosegli večje kontaktne kote (med 101,42˚ in 110,16˚) v primerjavi z uporabo zamreževalca EGDE (med 85,26˚ in 94,71˚), s čimer sklepamo, da so nanovlakna, zamrežena s PETA ob obsevanju z UV-svetlobo 40 min, stabilnejša ob stiku z vodo.Keratin, present in animal tissues such as feathers and wool, accounts for a large proportion of waste from the textile, agricultural and meat-processing industries. The drive to reduce negative environmental impacts makes it essential to convert these wastes efficiently into value-added products. The methods for extracting keratin from different sources differ mainly in the quality of the extraction product obtained and in their environmental impact, the main challenge being to use environmentally friendly extraction methods that yield keratin suitable for specific applications. This MSc thesis focuses on the development of stable nanofibres from keratin extracted from waste feathers and wool by a hydrothermal process using subcritical water. Due to the limiting values of the average molar masses in the extraction products, keratin was combined with polyethylene oxide (PEO) in 50/50 and 70/30 ratios. A needle-free electrospinning technique was used to produce the nanofibres. In order to improve the stability of the spun nanofibres, two crosslinking procedures were used, namely with ethylene glycol diglycidyl ether (EGDE) and with pentaerythritol triacrylate (PETA). The following properties were analysed on the spinning solutions before spinning: conductivity, viscosity, pH, surface tension, particle size, zeta potential and protein concentration. The chemical structure of the lyophilised keratin and the nanofibres produced was monitored by infrared spectroscopy (ATR-FTIR). Spinning electron microscopy (SEM) was used to analyse the nanofibre formation performance and contact angle measurements were used to analyse the hydrophilicity of the nanofibres. The ABTS method was used to determine the antioxidant capacity of the keratin/PEO and nanofibre solutions. The extraction yields of keratin from feather and wool waste were 87,46 % and 88,33 %, respectively. The SDS-PAGE technique was used to determine the maximum molar mass concentration of keratin in the suspension from feathers and wool in the range between 4,6 and 9 kDa. The results showed that nanofibres containing up to 70% keratin in blends with PEO can be produced from the lyophilised products. After crosslinking with PETA and EGDE, we were able to identify typical keratin peaks in the keratin/PEO blend nanofibres by ATR-FTIR. The antioxidant activity of the fabricated nanofibres was high (86.9% inhibition) and was not significantly affected by the crosslinking procedures. Higher contact angles (between 101.42˚ and 110.16˚) were achieved using PETA crosslinker compared to EGDE crosslinker (between 85.26˚ and 94.71˚), suggesting that PETA crosslinked nanofibres are more stable in contact with water when irradiated with UV light for 40 min
Manufacturing and testing of drying cabinet prototype
No full textSušilna omara je namenjena za sušenje in osveževanje mokrega ali suhega perila. Tako se oblačila posušijo, osvežijo in razkužijo s pomočjo pare. Sistem temelji na uporabi izmenjevalnika toplote oz. krajše kompresorja. Ta segreje topel zrak in ga s pomočjo ventilatorja gnanim z BLDC motorjem usmeri v zračni kanal na zadnji strani omare. Voda se prečrpa iz rezervoarja za čisto vodo v parni generator na vrhu omare, kateri upari in usmeri vodno paro v omaro, tako da odstrani gube na oblačilih, prav tako pa jih razkuži. Para kondenzira na dnu omare kjer je zračni usmernik in se s pomočjo črpalke prečrpa v rezervoar z umazano vodo. Sistem ima več različnih nastavitev, kot so samo sušenje, samo uporaba pare, sušenje in para, časovne programe, varnostno zaklepanje, in začetek sušenja z zamikom. Prav tako omara vsebuje WIFI modul, tako da lahko omaro upravljamo preko aplikacije.The drying cabinet is designed for drying and refreshing wet or dry laundry. This way, the clothes are dried, refreshed and disinfected with the help of steam. The system is based on the use of a heat exchanger, short for compressor, which heats the warm air and directs it into an air duct at the back of the cabinet using a BLDC electric motor, where a fan is also installed. Water is pumped from a clean water tank to a steam generator at the top of the cabinet, which vaporises and directs the steam into the cabinet, removing wrinkles from clothes disinfecting them. The steam is condensed at the bottom of the cabinet where the air rectifier is located, and pumped to the dirty water tank by means of a pump. The system has several different settings such as dry only, steam only, dry and steam, timer programmes, child lock, and delayed start. The cabinet also includes a WIFI module so that the cabinet can be controlled via an app
Creation of technical documentation for an assembly cell for the automated production of hinges
No full textV zaključnem delu smo se lotili izdelave načrta električnih inštalacij in tehnične dokumentacije za avtomatizirano montažno celico. Celica je končna postaja na liniji sestave tečajev v podjetju Turna, d. o. o. Zaključno delo zajema opis delovanja montažne celice, njeno zgradbo, komponente, načrt električnih inštalacij, navodila za varno delo in pomen naprave za proizvodnjo. Podobna montažna celica v podjetju že obstaja, a nova celica vsebuje nadgradnje oz. ima kakšno delovno enoto manj. Načrt električnih inštalacij smo narisali s pomočjo programa Eplan.In this bachelor thesis we created plans of electrical installation and technical documentation for automated assembly cell. The cell is the last station on the hinges production line in company Turna d. o. o. The bachelor thesis includes working description of the assembly cell, its structure, components, electrical installation plans, work safety instructions and meaning of the assembly cell for the production. A similar assembly cell already exist in the company, but the new cell contains upgrades, and it does not have as many working units. We created electrical installation plan using Eplan software
Software development for automatic configuration of led floodlights
No full textDiplomska naloga je nastala v sodelovanju s podjetjem SMT, ki izdeluje tiskana vezja za LED reflektorje, ki se uporabljajo v filmski industriji. Na vsakem vezju je potrebno nastaviti minimalno in maksimalno osvetlitev za LED diode, kar se je do zdaj počelo ročno, proces pa je trajal 5 do 10 minut. Cilj te naloge je narediti napravo, ki bi to naredila samodejno in hitreje.This thesis was created in collaboration with a company SMT that makes printed circuit boards for LED floodlights which are used in the movie industry. Minimal and maximal illumination for the LEDs must be set for each individual circuit. This is done by hand and usually takes between 5 to 10 minutes. The goal of this thesis is to create a device that will do this automatically and faster
Use of different hardfacing methods to enhance wear resistance
No full textNavarjanje je pomemben postopek povečevanja obrabne obstojnosti strojnih delov. V magistrski nalogi sta predstavljena postopka navarjanja z MAG tehnologijo in s PTA tehnologijo. Izvedli smo navarjanje z dodajnimi materiali, ki so trenutno v uporabi v podjetju Farmtech d. o. o., in jih primerjali z novima za uporabo s PTA in MAG tehnologijo. Za primerjavo smo izvedli test obstojnosti proti obrabi, meritev trdot v prerezu talonov in meritev površin namešanja. To smo nadgradili tudi s stroškovno in časovno analizo. Rezultati bodo služili kot smernice za odločitev k implementiranju PTA tehnologije v obstoječo proizvodnjo.Overlay welding is an important process for increasing the wear resistance of machine parts. In the master’s thesis, two welding processes are presented with MAG technology and PTA technology. We carried out welding with additive materials, which are currently in use in the company Farmtech d. o. o., and compared them with new ones for use with PTA and MAG technology. For comparison, we carried out a wear resistance test, hardness measurement in the cross-section of the samples, and measurement of mixing areas. We also upgraded this with a cost and time analysis. The results will serve as guidelines for the decision to implement PTA technology in existing production
Zasnova učinkovite strategije upravljanja ventilatorja za učinkovito hlajenje perifernih komponent motorja med toplotno obremenitvijo vozila
No full textThe aim of this Master\u27s thesis was to find a mathematical correlation between various fan momentum fields for a fan which is used for cooling the underhood area of a car. The correlation had to link a known momentum field to all possible momentum fields related to fan rotation speed and car velocity. With this correlation, new alternative fan steering strategies can be used to cool the vehicle underhood area.
An already functioning RBM (Rigid Body Motion) simulation was used as a base, since it already gave satisfying results in the past. With this simulation file, several tests were run to ensure that the results really converge nicely. In this way it was established that the results are accurate enough for further use. After obtaining the results, a set of 30 simulation files was calculated. The simulations were a combination of different fan rotation speeds and car velocities.
After the set was done, the results were analysed using various computer software (Star-CCM+, MS Excel and Matlab). It was concluded that a polynomial approach for the momentum field was a suitable option but to add some additional complexity, surface equations were used. To obtain the equations, tables with different results were put into Matlab and the program did the rest. The result were two sets of three surface equations with x and y values. In both cases, x represented the rotation speed of the fan and y represented the car velocity in one case and the delta pressure between two evaluation surfaces in the other.
After that it was time to implement the newly acquired surface equations in a Star-CCM+ simulation file. The old simulation file was again used as a base, but new field functions were put in with the help of which the UDMS (User Defined Momentum Source) is being changed. Both types of surface equations were tested and calculated. In the end, it was decided to go with the one where the delta pressure on two evaluation surfaces is being used as the y value. One surface was placed in front of the fan and the other after the fan.
The final step was to test different fan steering strategies. The usual cooling procedure consists of a phase where the fan cools for a specific amount of time with a defined rotation speed and then turns off. Temperatures on critical points around the engine and in the underhood area of the car are being looked at as a result.
The first strategy was to run the fan at the same speed as usual, but gradually slow it down in uniform steps so that the shut down time remains the same. With this approach, the highest temperature values were actually lower than usual, but certain temperature probes became warmer as the fan speed decreased. Nevertheless, the temperatures at the end were very similar.
The second tested strategy was inspired by the idea of potentially saving some battery energy if we could somehow manage to cool the underhood area quicker. In this case, the fan ran for a short time at a high rotation speed and after that at a slightly lower speed. Then it was turned off for a few minutes and subsequently switched back on. The maximum temperature in this scenario reached even higher values. The reason for this was that the fan blew warm air toward certain measurement points, causing them to heat up further. The temperatures at the end of the simulation were similar to those in the previous two cases.
In conclusion, it is indeed possible to steer a fan momentum field with the help of field functions and equations which describe the relationship between different fan rotation speeds and car velocities.Cilj te magistrske naloge je bil najti matematično korelacijo med različnimi vrtilnimi količinami ventilatorja za hlajenje območja pod pokrovom avtomobila. Korelacija je morala povezati znano vrtilno količino ventilatorja z vsemi možnimi vrtilnimi količinami, vezanimi na hitrost vrtenja ventilatorja in hitrost avtomobila. S to korelacijo je mogoče uporabiti nove alternativne strategije krmiljenja ventilatorja za hlajenje podvozja avtomobila.
Za osnovo je bila uporabljena že delujoča RBM (Rigid body motion) simulacija, saj je v preteklosti že dala dovolj dobre rezultate. S slednjo je bilo izvedenih nekaj testov, da so rezultati resnično dobro konvergirali. Na ta način je bilo zagotovljeno, da so rezultati dovolj dobri za nadaljnjo uporabo. Po pridobitvi rezultatov je bil izveden set tridesetih simulacij, katere so bile kombinacija različnih hitrosti vrtenja ventilatorja in hitrosti avtomobila.
Po izvedbi celotnega seta tridesetih simulacij, so bili rezultati analizirani s pomočjo različnih računalniških programov (Star-CCM+, MS Excel in Matlab). Ugotovljeno je bilo, da je polinomski pristop najprimernejši za vrtilno količino, za dodatno kompleksnost pa so bile uporabljene površinske enačbe. Za pridobitev teh enačb so bile v Matlab vstavljene tabele z različnimi rezultati, program pa je naredil preostanek. Rezultat sta bila dva niza treh površinskih enačb z vrednostmi x in y. Vrednost x je v obeh primerih predstavljala hitrost vrtenja ventilatorja, vrednost y pa je v enem primeru predstavljala hitrost avtomobila, v drugem pa razliko tlaka na dveh površinah, s pomočjo katerih je bil slednji beležen v področju pod pokrovom avtomobila.
Za tem je sledila implementacija novo pridobljenih površinskih enačb simulacijsko datoteko Star-CCM+. Za osnovo je bila ponovno uporabljena stara simulacija, kamor pa so bila vnesena nova funkcijska polja, s pomočjo katerih se spreminja vrtilna količina ventilatorja (UDMS – User defined momentum source). Obe vrsti površinskih enačb sta bili testirani in izračunani, na koncu pa je bila izbrana tista, kjer je za vrednost y uporabljena razlika tlakov na dveh površinah v območju pod pokrovom avtomobila. Ena je bila postavljena pred ventilator, druga pa za njim.
Zadnji korak je bil preizkus različnih strategij krmiljenja ventilatorja. Običajni postopek hlajenja je sestavljen iz faze, kjer ventilator določen čas hladi z določeno hitrostjo vrtenja in se nato ugasne. Preučujejo se temperature na kritičnih točkah v okolici motorja pod pokrovom avtomobila.
Prva strategija je bila sledeča: zagnati ventilator z enako hitrostjo kot običajno, vendar ga postopoma upočasnjevati v enakomernih korakih, da je na koncu čas zaustavitve še vedno enak. S tem pristopom so bile najvišje vrednosti temperature dejansko nižje od običajnih, vendar so se določene točke med procesom, ko se je hitrost ventilatorja zniževala, še dodatno ogrele. Kljub temu pa so bile temperature na koncu simulacije zelo podobne.
Druga preizkušena strategija je bila zasnovana po navdihu, da bi morda lahko prihranili nekaj baterijske energije, če bi nekako uspeli v krajšem času ohladiti območje pod pokrovom avtomobila. Ventilator je v tem primeru za kratek čas deloval z visoko hitrostjo, nato pa z nekoliko manjšo. Nato je bil za nekaj minut izklopljen in potem ponovno vklopljen. Izkazalo se je, da maksimalne temperature v tem primeru dosegajo še višje vrednosti. Razlog za to je bil v tem, da je ventilator pihal topel zrak v smeri nekaterih merilnih točk, ki so se zaradi tega še bolj ogrele. Temperature na koncu simulacije pa so bile kljub vsemu podobne kot v prejšnjih dveh primerih.
Skratka, ugotovljeno je bilo, da je vsekakor mogoče krmiliti vrtilno količino ventilatorja s pomočjo funkcijskih polj in enačb, ki opisujejo razmerje med različnimi hitrostmi vrtenja ventilatorja in hitrostmi avtomobila