Due to historically low prices for electricity in Sweden, many small-scale hydropowerplants were closed down. A small-scale power plant has more or less the samemaintenance costs as larger plants, but doesn’t generate as much income. Today’sincreasing price for electricity in combination with a desire for renewable energysources makes small-scale hydropower interesting again. The sawmill in Venås is afacility of that kind. During the 1920´s two Francis turbines were installed as powersource for the machinery and a small private DC-grid. In 1966 the dam collapsed andthe facility was therefore retired. There is a possibility that the station can once againbe used as a power station to feed electricity to the grid. This will demand a largeamount of work and economic investment. Therefore is both technical andeconomical calculations needed in order to get the facility profitable. This reportincludes such calculations for the Venås station.

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One of the global sub-goals states that rehabilitation and adaptation of industrial infrastructure is important for making industries more sustainable, with more efficient use of resources by year 2030. Increased energy prices, strict environmental requirements, new control instruments for efficient end use of energy have created an increased desire to reduce energy use and related energy costs. Sweden has a goal of increasing the renewable electricity production by 18 TWh by year 2030 using the control instrument electricity certificate. Energy efficiency can be achieved at: the different kinds of processes in the mill, assistant systems, and heat and electricity supply (power generation). In this study, the main focus will be on power generation. The paper and pulp industry uses large amounts of different energy types in all processes in the factory. In this study, the focus is on the energy type steam. One of the basic requirements that a cogeneration system needs to follow is the steam pressure requirements of all the steam-consuming processes in the mill. In this study, all the steam-consuming processes on the low-pressure network have been investigated. The study is limited to the month of September year 2018. The system boundaries start from the recovery boilers and the bark boiler, and then the steam path is followed through the grid and ends at the steam consuming processes. The method is divided into two main parts: In the first part, a calculation model of the zero system was constructed. The second part is a study of the pressure requirements of the steam consuming processes on the low-pressure side. It is possible to demand control the turbine. The evaporation processes control the demand system. The other processes that limiting the lowest pressure are considered to be: The feed water tank and the receiver (at drying machine 8). The low-pressure network can be reduced from 3.2 to 2.92 bar (over pressure) without any applications. The pressure may be further reduced if a technical investigation is carried out over the turbine. The minimum design pressure of the steam consuming processes is considered 2.5 bar (over pressure). The pressure limit: 2.92 bar (over pressure) gave a cost reduction of 2.64 million SEK per year. 2.5 bar (over pressure) gave a cost reduction of 4,69 million SEK per year. Optimized operation is considered an approval measure for the allocation of electricity certificates. 8982 electricity certificates will be given if it is 100 percent allocation of electricity certificates of the turbines generated electricity with a design reduction of the pressure to 2.5 bar (over pressure). The certificates then corresponds to an income increase of 2.25 million SEK per year.

Den här rapporten är ett resultat av ett examensarbete i ämnet maskinteknik med inriktning bistånd genomfört vårterminen 2010. Arbetet är ett samarbete med den svenska organisationen Ankarstiftelsen, som har bistått studenterna med kontakter i Leticia, Colombia. Arbetet har varit förlagt dels i Sverige och dels i Leticia, Colombia och har bestått av en förstudie i Leticia samt en litteraturstudie. Målet med arbetet har varit att ta fram ett förslag på lämplig placering och val av turbinsystem, utifrån de förutsättningar som finns i området. Rapporten presenterar olika metoder för elproduktion i Amazonasregionen, turbinsystem anpassade för strömmandevattenkraft och resultat från förstudien. Rapporten presenterar ett förslag där en turbin av modellen Darrieus installeras på en ponton vid samhället Milagrosa. Turbinen beräknas i dagsläget täcka det elbehov som finns i samhället. Dock kvarstår finansieringsfrågan. / This report is the result of a thesis project in mechanical engineering with focus on development assistance, completed spring term 2010. The work is collaboration with the Swedish organization Ankarstiftelsen, which has assisted the students with contacts in Leticia, Columbia. The work has been taken place in both Sweden and Leticia, Colombia. A literature review was carried out in Sweden and a pilot study in Leticia. The goal of this work has been to develop a suggestion on a proper placement and selection of turbine systems, based on the parameters that have been encountered. The report presents various methods of electricity production in the Amazon region, turbine systems suitable for hydrokinetic power and the results from the pilot study. The report presents a suggestion where a Darrieus turbine is installed on a pontoon close to the community Milagrosa. The turbine is expected in the current situation to cover the electricity needs of the community. However, the funding issue still remains to be solved.

<p>Den här rapporten är ett resultat av ett examensarbete i ämnet maskinteknik med inriktning bistånd genomfört vårterminen 2010. Arbetet är ett samarbete med den svenska organisationen Ankarstiftelsen, som har bistått studenterna med kontakter i Leticia, Colombia.</p><p>Arbetet har varit förlagt dels i Sverige och dels i Leticia, Colombia och har bestått av en förstudie i Leticia samt en litteraturstudie. Målet med arbetet har varit att ta fram ett förslag på lämplig placering och val av turbinsystem, utifrån de förutsättningar som finns i området.</p><p>Rapporten presenterar olika metoder för elproduktion i Amazonasregionen, turbinsystem anpassade för strömmandevattenkraft och resultat från förstudien.</p><p>Rapporten presenterar ett förslag där en turbin av modellen Darrieus installeras på en ponton vid samhället Milagrosa. Turbinen beräknas i dagsläget täcka det elbehov som finns i samhället. Dock kvarstår finansieringsfrågan.</p> / <p>This report is the result of a thesis project in mechanical engineering with focus on development assistance, completed spring term 2010. The work is collaboration with the Swedish organization Ankarstiftelsen, which has assisted the students with contacts in Leticia, Columbia.</p><p>The work has been taken place in both Sweden and Leticia, Colombia. A literature review was carried out in Sweden and a pilot study in Leticia. The goal of this work has been to develop a suggestion on a proper placement and selection of turbine systems, based on the parameters that have been encountered.</p><p>The report presents various methods of electricity production in the Amazon region, turbine systems suitable for hydrokinetic power and the results from the pilot study.</p><p>The report presents a suggestion where a Darrieus turbine is installed on a pontoon close to the community Milagrosa. The turbine is expected in the current situation to cover the electricity needs of the community. However, the funding issue still remains to be solved.</p>

The gas turbine has an important role for the energy distribution due to its stability and flexibility. By increasing turbine inlet temperature (TIT) an increased thermal efficiency of the turbine can be achieved. The biggest limitation of the TIT is the material of the turbine components. To avoid this limitation, cooling is needed in the first stages of the turbine by air from the compressor. The downside of the cooling is the decrease of efficiency with excess of cooling air. To achieve an optimum cooling flow, the designing process is important. One major tool in the designing process is simulations by Computational Fluid Dynamics (CFD). For optimum and correct cooling design, the CFD simulations needs to accurate predict the temperature transport through the turbine. Therefore, this study focused to estimate the accuracy of different CFD methods in predicting the temperature distribution through a 1.5 stage turbine with experimental results. The CFD simulations were done by using Ansys CFX and divided into two study cases with steady RANS. One with different turbulence models;  –, Wilcox –  and SST – . The other with two different simulation approaches of interfaces for frame change; Mixing plane and Frozen rotor. All simulations included two configurations of swirlers clocking for interest of their differences within the turbine and validation of the CFD simulations; Passage (PA) and Leading Edge (LE) clockings. The experimental results showed a formation of gradually more uniformed temperature profile with the fluid. This could not be seen in the same extend with any of the simulations. The temperature difference between the hot and cold section with all simulations were marginally decreased in comparison of the measurements. All results with steady RANS simulations tended to over and under predict the temperatures of the hot respectively cold sections within the fluid flow through the turbine. This occurred already after the first stage guide vanes and the difference from the measurements increased after the first stage rotor. This since the steady RANS tended to under predict the mixing process through the turbine. Differences between the turbulence models were noticeable after the rotor blades, where the   – turbulence model predicted most mixing of the evaluated turbulence models but badly compared to the measurements. Another outcome from this study was that the frozen rotor interface with several positions of the rotor blades did not stated better results compared to mixing plane interface for temperature distribution in axial turbines. On the other hand, one simulation of one position of the rotor with frozen rotor interface could be used to simulate an approximatively similar circumferential average temperature as the mixing plane with better convergence with the disadvantage of bigger domain. The gas turbine has an important role for the energy distribution due to its stability and flexibility. By increasing turbine inlet temperature (TIT) an increased thermal efficiency of the turbine can be achieved. The biggest limitation of the TIT is the material of the turbine components. To avoid this limitation, cooling is needed in the first stages of the turbine by air from the compressor. The downside of the cooling is the decrease of efficiency with excess of cooling air. To achieve an optimum cooling flow, the designing process is important. One major tool in the designing process is simulations by Computational Fluid Dynamics (CFD). For optimum and correct cooling design, the CFD simulations needs to accurate predict the temperature transport through the turbine. Therefore, this study focused to estimate the accuracy of different CFD methods in predicting the temperature distribution through a 1.5 stage turbine with experimental results. The CFD simulations were done by using Ansys CFX and divided into two study cases with steady RANS. One with different turbulence models;  –, Wilcox –  and SST – . The other with two different simulation approaches of interfaces for frame change; Mixing plane and Frozen rotor. All simulations included two configurations of swirlers clocking for interest of their differences within the turbine and validation of the CFD simulations; Passage (PA) and Leading Edge (LE) clockings. The experimental results showed a formation of gradually more uniformed temperature profile with the fluid. This could not be seen in the same extend with any of the simulations. The temperature difference between the hot and cold section with all simulations were marginally decreased in comparison of the measurements. All results with steady RANS simulations tended to over and under predict the temperatures of the hot respectively cold sections within the fluid flow through the turbine. This occurred already after the first stage guide vanes and the difference from the measurements increased after the first stage rotor. This since the steady RANS tended to under predict the mixing process through the turbine. Differences between the turbulence models were noticeable after the rotor blades, where the   – turbulence model predicted most mixing of the evaluated turbulence models but badly compared to the measurements. Another outcome from this study was that the frozen rotor interface with several positions of the rotor blades did not stated better results compared to mixing plane interface for temperature distribution in axial turbines. On the other hand, one simulation of one position of the rotor with frozen rotor interface could be used to simulate an approximatively similar circumferential average temperature as the mixing plane with better convergence with the disadvantage of bigger domain. / Gasturbinen har en viktig roll i nutida och framtida energidistribution för elektricitet på grund av dess stabilitet samt flexibilitet. Genom att öka temperaturen in till turbinen ökar den termiska effektiviteten. Den största begränsning av denna temperaturökning är materialen av komponenterna i turbinen. För att kringgå detta används kylning i turbinen med luft från kompressorn. Effektiviteten kan däremot minskas vid överdriven användning av kylluft och därav är designen av kylningen viktig för optimal användning av kylluft. Ett verktyg som oftast används vid design av turbiner är simuleringar med Computational Fluid Dynamics (CFD). För att uppnå en optimal design av kylningen behöver CFD simuleringarna korrekt prediktera temperaturtransporten genom turbinen. Därför fokuserade denna studie på att uppskatta och validera olika CFD metoders förmåga att prediktera temperaturtransporten genom en 1,5 stegs axiell turbin med experimentella resultat. Stationära CFD simuleringar gjordes med RANS av olika turbulensmodeller; k – ε, Wilcox k – ω and SST k – ω. Dessutom jämfördes två olika sätt att simulera gränssnittet mellan stationära och roterande domän; Mixing plane och Frozen rotor. Samtliga simuleringsmetoder inkluderade två olika konfigurationer av virvlarepositioner; Passage (PA) och Leading edge (LE) klockningar. Experimentella resultat visade en stegvis mer enhetlig temperaturprofil med fluidflödet genom turbinen. Detta sågs dock inte i samma utsträckning i någon av simuleringarna. Temperaturskillnaden mellan de varma och kalla stråken i samtliga simuleringar minskade marginellt i jämförelse med de experimentella resultaten. Samtliga resultat med stationära RANS simuleringar tenderade att över och under prediktera temperaturen av de varma respektive kalla stråken. Detta inträffade redan efter förstastegsledskenorna, där skillnaden från de uppmätta temperaturerna ökade över första stegs rotor. Detta på grund av att mixningen i fluiden under predikterades. Skillnader mellan de olika turbulensmodellerna var synliga efter första stegs rotor där  – turbulensmodell predikterade mest mixning av samtliga simuleringar av turbulensmodeller. Däremot predikterade den marginellt bättre i jämförelse med mätningarna. Andra resultat från denna studie var att gränssnittet med frozen rotor med flera positioner inte anger bättre mixning av fluiden genom rotordomänen än vad gränssnittet med mixing plane där liknande radiella temperaturprofiler fås. Däremot gav en simulering med en position av rotorn liknande resultat med radiellt fördelade temperaturer som mixing plan och skulle kunna användas för approximativa simuleringar med bättre konvergens.

The expansion of the Swedish hydro power has contributed positively to the reduction of the environmental impacts from the fossil fueled power production. In the same time the extensive expansion has been proved to cause negative ecological and local environment impacts of a stream. This, in turn, has been affecting the biodiversity and fish stock negatively, which has been reduced. One of the underlying problems is the lack of possibility for the fish to pass the plants, but it is also directly correlated to the mortality rate of the fish passing through the turbine, which this study is investigating. The mortality rate has been computed for three different locations in Sweden, Untra, Tännfallet and a third one whose location is confidential, and is denoted as Case 1, 2 and 3. The model used to calculate the mortality rate in this investigation is based by existing blade strike models and knowledge and are investigating the death due to mechanical injuries from collision with a runner blade in the turbine. The model is valid for Kaplan- and Francisturbines and is taking technical design, physiological and behavioral parameters, in consideration. In the first case, Untra, the mortality rate is lower for the Kaplan turbines than for the Francis turbine that has been under investigation. However the Francis turbine has lower mortality rate at low loads and the result also indicates that a Kaplan turbine with greater diameter has lower mortality rate than a smaller one. In case 2, Tännfallet, the Kaplan turbine would give 50 % lower mortality rate than a Francis turbine with a corresponding drop and water intake and at full load. At part load the mortality rate is 42 % less. Case 1 and 2 indicates that a Kaplan turbine is more fish friendly than a Francis turbine, but Case 3, indicates the opposite. The mortality rate in the old Francis turbine was 0 % according to the calculations. This could be explained to the low relative velocity, which is partly a result of the small scale turbine. The relative velocity is in this case is well below 10 m/s and a collision with the runner blades has not necessary a deadly outcome.    In all cases the trash rack is of great importance to prevent a fish with high probability to die in the turbine to pass. In Untra a rack with a gap width of 20 mm is recommended. This would prevent 25 cm long fish and 80 cm long eels to pass. In Tännfallet the current rack that has a gap of 25 mm is considered to be sufficient and will prevent a 30 cm long fish and 90 cm long eels. In Case 3 an 18 mm wide rack is recommended and if choosing that the mortality rate in Case 3 will be at most 26 % if a fish is passing and 70 % for the eel, these with a length of 25 and 70 cm respectively. The results from the case study and the analysis indicates that the mortality rate due to fish passing through the turbine can be reduced. Partly by choosing a turbine that is more fish friendly designed, but also by using optimally designed diverters as trash racks. In general the mortality rate increases with the length of the fish and with a reduction in the turbine dimensions, but at relative velocities below 10 m/s the mortality rate are reduced. This occurs in more extent in Francis turbines, but in general the Kaplan turbine has a lower mortality rate. Also to be mentioned, there are a lot of uncertainties when calculating the mortality and the technical parameter that has the most influence to the mortality rate is the relative flow angle (runner blade angle). Another uncertainty is the behavior of the fish. For example, the mortality rate is much greater for a fish passing at the top of the impeller in a Francis turbine than one passing at the bottom. Hopefully, the knowledge given in this report will contribute to future investigations where the best possible technique to reduce the mortality of a fish passing through the turbine is to be done, and thereby promote both the environmental and economic sustainability of the hydro power.

<p>The thesis investigates if it is possible to replace several pumpimpellers with one controllable pumpimpeller, with a economical and a manufacturing analisys aspect. The studied pumpimpeller is mounted on a midrange wastewaterpump, N3127MT.</p><p>In the thesis a contemplated manufacturing process is evaluated for a concept that are supposed to act as a controllable pumpimpeller. The pumpimpeller are studied in a manufacturing and flow matter and are presented in the thesis.</p><p>The manufacturing cost is also estimated, and this has been compared to the storage cost and other costs that the existing pumpimpeller generates.</p><p>The thesis also shows that the concept has minor losses in cutting quality aswell as the effiency comparing to the existing pumpimpeller.</p><p>The concept also raises the manufacturing cost and this increasing cost makes the presented concept to expensive to carry through.</p><p>An investigation of the costs that the existing pumpimpeller produces has also been done, and this shows that there is not that much expenses to earn regarding to for example the storage cost. The storage cost includes information from Flygt’s central storagecenter in Lindas, Sweden and Metz, France, and also an inventory about the pumpimpellers located at Flygt’s different distributors worldwide.</p><p>The thesis shows that a controllable pumpimpeller will generally increase the cost for the pumpimpeller and the performance of the pumpimpeller will decrease.</p>

Denna rapport sammanfattar det examensarbete som utförts 2012 på kandidatnivå av Erika Dahlström och Josefin Hult på Mälardalens Högskola i Eskilstuna. Examensarbetet har utförts i samarbete med ÅF Technology AB i Västerås. Projektets idé uppstod i ett tidigare fiktivt högskoleprojekt där tanken om ett vindkraftverk skulle vara intressant för privatpersoner kom till. Detta projekt har vidareutvecklat denna tanke och projektet har då utvecklats till att syfta till att undersöka om det finns en marknad för miniverk i byggsatsform avsett för privatpersoner, vad marknaden efterfrågar samt utveckla och konstruera en miniverksmast. Ett miniverk är ett vindkraftverk som vanligtvis inte behöver bygglov. För att kunna besvara hur marknaden ser ut har omfattande research utförts samt en marknadsundersökning. Från researchen sågs att det finns liknande befintliga produkter vilket innebar att projektets syfte gick från att konceptutveckla ett helt miniverk till att differentiera vår produkt från konkurrenternas. Detta gjordes genom att utveckla en mast som ger brukaren större valmöjligheter genom bland annat underlätta montering samt underhåll av sitt miniverk. Vid konstruktion har fokus lagts på knäckningsberäkningar då knäckning måste tas på största allvar för att undvika potentiellt allvarliga olyckor. Beräkningar har jämförts med simuleringar utförda i Solid Works vilket visar på att beräkningarna bör vara korrekta. Resultatet blev en 15,4 meter hög mast uppdelad i fem sektioner. Masten höjs och sänks genom en vev, block och vajrar. För att säkra att masten står stabilt finns åtta stycken stabiliserande vajrar fästa på två mastsektioner. Denna mast uppfyller majoriteten av de krav som ställts upp i en kravspecifikation. Att alla krav inte kunde uppfyllas beror på projektets begränsade tid. Dock har tydliga rekommendationer getts för att möjliggöra en vidareutveckling av detta resultat så att alla krav kan uppfyllas. Under hela produktutvecklingsprocessen har ett flertal olika produktutvecklingsverktyg använts som stöd och kvalitetssäkring i arbetet. Arbetet med projektet har fungerat väl, dock var en del frågor inom projektet mycket komplexa vilket innebar en del förseningar.

The thesis investigates if it is possible to replace several pumpimpellers with one controllable pumpimpeller, with a economical and a manufacturing analisys aspect. The studied pumpimpeller is mounted on a midrange wastewaterpump, N3127MT. In the thesis a contemplated manufacturing process is evaluated for a concept that are supposed to act as a controllable pumpimpeller. The pumpimpeller are studied in a manufacturing and flow matter and are presented in the thesis. The manufacturing cost is also estimated, and this has been compared to the storage cost and other costs that the existing pumpimpeller generates. The thesis also shows that the concept has minor losses in cutting quality aswell as the effiency comparing to the existing pumpimpeller. The concept also raises the manufacturing cost and this increasing cost makes the presented concept to expensive to carry through. An investigation of the costs that the existing pumpimpeller produces has also been done, and this shows that there is not that much expenses to earn regarding to for example the storage cost. The storage cost includes information from Flygt’s central storagecenter in Lindas, Sweden and Metz, France, and also an inventory about the pumpimpellers located at Flygt’s different distributors worldwide. The thesis shows that a controllable pumpimpeller will generally increase the cost for the pumpimpeller and the performance of the pumpimpeller will decrease.