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228 Uppsatser om Kaplan turbine - Sida 5 av 16

Turbinkretspump system - Kraftvärmeverket i Borås

The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.

Expansionsmaskiner istället för strypventiler - en effektivisering

In Uppsala CHP Plant, there are six pressure reducing valves to reduce the pressure from 15 to 3 bars, before six absorption heat pumps. During the process the energy is conserved but losses occur in form of exergy. The aim of this thesis is to reduce the losses of exergy. This can be done by letting turbines replace the pressure reducing valves.In this thesis an investigation has been done of the conditions today, the conditions after the change from pressure reducing valves to turbines and a comparison of three different types of turbine solutions. The three examined solutions are one turbine, several helical screw expanders and several small turbines in parallel with asynchronous generators.The six absorption heat pumps have been divided into two groups; one group of four and one group of two absorption heat pumps.

En studie av olika ekonomiska modeller för mångbruk baserad på vindkraft

Today produces the wind power 2,5 TWh (TWh = terawatt hours) of Sweden?s total energy input of around 620 TWh. The Parliament has adopted a national planning objective where the wind-based electricity production will increase to 30 TWh in 2020. This requires that landowners will leas there land for wind power to wind energy companies. Such land leasing means that the landowner's business is considered to be a multiple-use.

Skogs påverkan på vindkraftsproduktion - en fallstudie av vindkraftverk vid Andersfält.

The purpose of this master thesis is to investigate how nearby forests affect the energy production in wind turbines. To reach the purpose a case study is performed on three wind turbines sited on a field in a north-south line at Andersfält in the municipality of Halmstad, Sweden. Approximately 100 meters south of the southern wind turbine a forest is situated. The case study is divided into three sub studies where the difference in energy production, the affect of the forest and a wind meteorology model, WAsP, is studied. The result show that the forest have a significant influence and that the WAsP-model gives an incorrect result of the energy production in wind turbines sited near a forest..

Aerodynamisk optimering av vindkraftverks rotorblad med en genetisk algoritm, BEM-teori, och XFOIL

This study presents a methodology that enables the annual average power of a wind turbine to be increased by automatically optimizing it?s airfoil, twist and chord dis- tribution. As a part of the study the software SiteOpt has been developed. This software connects the open source software XFOIL with the blade element momen- tum theory. XFOIL gives lift and drag coefficients which enable the blade element momentum theory to predict the power of a wind turbine at different wind and ro- tational speeds.

Kraftanalys och framtagning av mätanordning för vertikala vindkraftverket Lucias bärarmar

The project contains a force analysis of the vertical axis wind turbine Lucia's supporting arms and a measuring device to experimentally measure the forces is made. The forces between the supporting arms and the tower are calculated theoretically and then simulated by a computere. A measuring devise is then designed to measure the forces experimentally. The forces acting on the attachment between the supporting arms and the tower is primarily the centripetal force, gravitational force and the aerodynamic forces on the rotor wings. The maximum forces were theoretically calculated and is 13.38 kN along the x-axis, -0.25 kN along the y-axis and then 0.5 kN along the z-axis.

Feldiagnos för RM12 baserad på identifierade modeller

The jetengines of today are growing in complexity. Reliability for aircraft engines are of extreme importance, mainly due to safety reasons but also economical ones. This master thesis deals with faultdiagnosis in the turbine section of RM12, the engine used in Saab/BAe's Gripen. Three different faults which can occur in the turbine section was studied. These faults are: clogged fuel nozzle, hole in outlet guide vane and sensor fault.

Balanced Scorecard inom kommunal verksamhet

Background: From the beginning of the 60´s until the beginning of the 80´s the swedish local government has expand enourmously. The expansion didn´t lead to any discussions about how the local government should be controlled or organized. The local government should instead be organized and controlled as administrations. Lately it has became more usual to have these discussions about how local government should be controlled and organized. Nowadys it´s not unusual that local governments imitate private companies.

Balanced Scorecard ? En studie på ledningsnivå om kommuners tolkning av modellen

Syftet med föreliggande uppsats var att belysa hur tre utvalda kommuner, Helsingborg, Vellinge och Klippan, har tolkat styrmodellen Balanced Scorecard (BSC) i kommunal verksamhet. Uppsatsen baseras i huvudsak på intervjuer med tjänstemän på ledande nivå inom de tre kommunerna. Den teoretiska utgångspunkten har varit Kaplan & Nortons Balanced Scorecard, där teorin jämförts med hur ledningen inom kommunerna tolkat modellen från den privata sektorn. BSC är ett flerdimensionellt styrverktyg, bestående av fyra perspektiv; finansiellt, kund-, process- och lärandeperspektivet. Modellen är ursprungligen gjord för att användas inom vinstdrivande företag, och måste således omarbetas för att användas inom kommuner.

Modell och analysverktyg för beräkningav frekvensförlopp

The power system modelled in this thesis work has been developed for simulationwhen e.g. the production in some part of the power system is changed. The powersystem has been modelled according to the swing mass of the system, the frequencydependency of the load and the turbine governor. The model determines the systemfrequency, the period of regulation and the power exchange between the differentsubsystems in the Nordic synchronized system.In this model the system frequency is assumed to be the same in all different parts ofthe power system and the voltage conditions in the power system are neglected. Forthat reason power swings does not occur between different subsystems in the powersystem, which usually occur as a result of the swinging connection between thetransmissions line.

Investeringsbeslut för småskalig vindkraft : en fallstudie

Wind power is one of the sources of renewable energy which has to be developed further in order to lessen our dependence on non renewable sources of energy. It's mainly oil and coal which have to be replaced by green energy. Wind power is already established in many countries, for example Germany, The United States of America and Denmark but it has to be continually developed and expanded to meet the needs of the growing energy consumption in the world. During the last few years many types of small wind turbines have appeared on the market. These small wind turbines are an alternative to the big wind turbines or power generators which demand huge sums of investment money.A new target group can now buy the small wind turbines in order to cover their own usage of electricity.

Småskalig elproduktion i Arvika

Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner.The purpose with this rapport was to do a basic study for the specific system at Arvika where it?s possible to see the potential production of electricity that follows an installation of a flasbox.The final goal was to introduce an economic analysis of a flashox installation at given conditions.To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox.

Arbetslivsinriktad rehabilitering för sjukskrivna arbetslösa - funkar det?

En av de mest debatterade politiska frågorna de senaste åren har varit den påstått kraftiga ökningen av antalet sjukskrivningar. Parallellt med sjukskrivningarna har även antalet förtidspensionärer ökat. En grupp som inte uppmärksammas lika ofta av varken politikerna eller medierna är de människor som både är sjukskrivna och arbetslösa, och det är den gruppen som vår uppsats kommer att kretsa kring. Syftet med denna uppsats är att utvärdera försäkringskassans och arbetsförmedlingens samverkan kring den gemensamma kundgruppen sjukskrivna arbetslösa. Denna samverkan har bedrivits i Uppsala län sedan september 2003.

Reglering av turbins ledskenor i vattenkraftverkmed hjälp av elektriska ställdon

Hydropower is the largest renewable energy source available in today's society. Operation and production is handled by high-tech electronics. This thesis is done on behalf of Statkraft Sweden AB who wants to explore the possibility of replacing the hydraulic cylinder with an electric actuator, generally as well as a case of a small power station on the river Nissan. Whether it is the chaplain or francis turbine vanes are actuated by hydraulic cylinders. Because of Gustavsberg hydropower is inconstant operation, this report is based on power calculations, which are read and computed according to the available hydraulic diagram.

Återhämtning i gröna miljöer vid fysisk och psykisk ohälsa - en kartläggning

Dagens prestationsinriktade samhälle med den stress det innebär, medför att utbrändhet med sjukskrivningar till följd, ökar. Långvarig stress utan möjlighet till återhämtning är tärande på kroppen, och kan på sikt ge upphov till en rad allvarliga sjukdomstillstånd, så som hjärt- kärlsjukdomar, diabetes och depression (Annerstedt, Matilda, muntligen, 2012-05-04). Att naturen inger en känsla av lugn och avkoppling är något vi varit medvetna om länge (Norfolk, 2000, sid. 19). Men det är under de senaste 30 åren som olika forskare på ett mer vetenskapligt sätt undersökt naturens inverkan på hur vi mår. Resultaten pekar på att vistelse i gröna miljöer, men även att blicka ut över ett naturområde, fungerar avstressande och hälsofrämjande.

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