The stable operating range of axial compressors is limited by the onset of rotating stall and surge. Mass injection upstream of the tip of an axial compressor rotor is a stability enhancement approach which can be effective in suppressing stall in tip-critical rotors, and thus increasing the operating range of compressors. In this article, investigations on active flow control related to the rotor tip gap sensitivity are discussed. The experiments were performed in a 1.5-stage low-speed research compressor. Measurements at part speed (80 per cent) and full speed (100 per cent) with varying injection rates are discussed. These tests were performed for two rotor tip clearances of 1.3 per cent and 4.3 per cent of rotor blade tip chord. Results on the compressor map, the flow field as well as transient measurements to identify the stall inception are discussed. Supplementary, the numerical results are compared to the experiments based on the configuration with the greatest benefit in operating range enhancement.

An increased understanding of how inlet flow distortion affects transonic fans enables improved fan design and performance prediction. Inlet distortion refers to non-uniformities in the incoming flow properties. Complex inlet ducts in high performance aircraft result in distorted flow at the fan inlet. In this thesis, two studies were performed using Unsteady Reynolds-Averaged Navier Stokes (URANS) simulations. The first study focused on understanding how the transition abruptness between the clean and distorted sector in the inlet Pt profile as well as the circumferential extent of the distorted sector affect distortion transfer and generation through a transonic fan. Simulations on two main distortion sector sizes were carried out. For each sector size, variants with decreasing levels of transition abruptness were applied to the inlet of fan. Simulations were conducted at various operating points, ranging from choke to near-stall. Fourier-based distortion descriptors were used to quantify levels of distortion transfer and generation at various axial locations. It is shown that variations in rotor incidence occur as a result of the applied Pt distortion at the inlet. A less abrupt transition diminishes the local extrema in rotor incidence, which in turn reduces the amount of distortion transfer and generation through the rotor. The near-stall condition is affected most of all operating points considered, with a 23.4% average reduction in the amount of distortion transfer at any span. The size the inlet distorted sector affects the amount of distortion transfer and generation, particularly at the near-stall operating point. This is shown to be due to the dynamic response of the fan. The second study compared the mechanisms of stall inception for cases of both clean and distorted inlet flow. In each instance, the mechanism of stall inception is shown to be interactions between the detached bow shock and the tip clearance vortex. These interactions result in the formation of two vortices within the blade passage. The location and strength of these vortices affect the LE spillage in the adjacent blade rows. Stall inception occurs when the bow shock has moved far enough upstream to allow the resultant vortices from shock/tip clearance vortex interaction to pass in front of the leading edge. When inlet distortion is present, mass redistribution upstream of the fan results in variations in rotor incidence. Within the high incidence region, the bow shock is detached 3.9%-8.1% chord more than the clean inlet case, making LE spillage more severe. The rotating stall cell grows out of the stalled passages present at the near-stall operating point and ultimately extends 180° circumferentially and 18.7% span radially. Understanding the effects of distortion on the mechanisms of stall inception will allow appropriate steps to be taken to extend the stable operating range of modern commercial and high performance fans.

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Åkergården är ett projekt som ämnar att stärka och fastställa identiteten av ett bostadsområde under utveckling genom att spegla dess omgivning. I tid med detta projektförslag håller det på att byggas bostäder för cirka 700 personer i Källberga, som är omgiven av skogar, åkermark, och ett mindre häststall. Visionen är att skapa “en stadsdel på landet”, varav Åkergården blir en utökning av detta område och erbjuder funktioner i linje med ett stadsliv på landet. Projektprogrammet inkluderar en medelstor veterinärklinik, djurbutik, ett mindre häststall som samarbetar med det som nu redan finns, hovslagare, kontorsutrymmen, och en djurvänlig cafe-lounge. Projektområdet är placerat på en för tillfället oanvänd åkermark, vilket tillåter användning som tar tillvara på den, som att utöka betesmark för hästar eller till och med andra djur. Åkergårdens form och estetik efterliknar häststallet som finns i närheten idag för att skapa en visuell dialog mellan dem. Användningen av betong möjliggör samarbete med en lokal producent för att skapa en starkare lokal sammanhållning, samtidigt som det har passande egenskaper för den typ av mark projektet ligger på. Åkergården siktar mot att göra “en stadsdel på landet” trovärdigt. / The Farm Shelter is a project attempting to strengthen and solidify the identity of an up and coming residential area by reflecting its surroundings. In time with the project proposal, housing for approximately 700 residents is being developed in Källberga, located close to forests, farmland, and a minor horse stables. The vision is to create “a city district in the countryside”, and thus The Farm Shelter serves as an extension of Källberga, contributing with services fit for the countryside city life. The project program fits an average scale veterinary clinic, pet shop, smaller horse stables synergizing with the pre-existing local one, a farrier, office spaces, and an animal-friendly lounge-cafe. The project site is located on currently unused farmland, enabling uses that take advantage of the soil, like providing additional pasture for horses or even other animals. The form of aesthetic of The Farm Shelter takes great inspiration from the local horse stables to enable visual association. The use of concrete supports the affiliation of a local producer nearby, further strengthening local bonds, as well as serves functional purposes considering the site conditions. The Farm Shelter aims to make “a city district in the countryside” believable.

Inlet distortion is an important consideration in fan performance. Distortion can be caused through flight conditions and airframe-engine interfaces. The focus of this paper is a series of high-fidelity time accurate Computational Fluid Dynamics (CFD) simulations of a multistage fan. These investigate distortion transfer and generation as well as the underlying flow physics of these phenomena under different operating conditions. The simulations are performed on the full annulus of a 3 stage fan. The code used to carry out these simulations is a modified version of OVERFLOW 2.2 developed as part of the Computational Research and Engineering Acquisition Tools and Environment (CREATE) program. Several modifications made to the code are described within this thesis. The inlet boundary condition is specified as a 1/rev total pressure distortion. Simulations at choke, design, and near stall points are analyzed and compared to experimental data. Analysis includes the phase and amplitude of total temperature and pressure distortion through each stage of the fan and blade loading plots. An understanding of the flow physics associated with distorted flows will help designers account for unsteady flow physics at design and off-design operating conditions and build more robust fans with a greater stability margin.

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Syftet med denna kvalitativa studie med kvantitativa inslag var att ge en bild av elevers välmående på ett ridgymnasium samtidigt som jag ville belysa betydelsen av elevers gemenskap och trivsel. Sammanfattningsvis tyder resultatet av min studie på att elever som går på ett ridgymnasium och dagligen får bedriva studier parallellt med hästar mår bättre psykiskt och känner sig nöjda och tillfreds, samt utvecklas som människor. Samspelet mellan eleverna och deras hästintresse skapar en känsla av att eleverna känner sig nöjda med sig själva.

Platsen för Mora Kulturhus definieras av den omgivande landsbygden; jordbruk, skog och det intilliggande stallet. En kilometer bort rinner Moraån och på andra sidan den börjar Järnas täta bostadsområden. Mora kulturhus ligger i den södra delen av Mora, området vi ritade i höstens kurs, och är placerat i förlängningen av rekreationsområdet vid Moraån. Med vandringsled och cykelväg kopplas Järna, Mora och Mora Kulturhus samman och gör platsen lättillgänglig för områdenas invånare. Huvudleden genom Mora som kopplar samman Nykvarnsvägen i norr och väg 57 i söder ger besökare olika vägval mot Mora kulturhus.   Platsen och Kulturhuset möjliggör att olika intressen kan samverka, samexistera och skapa gruppidentitet över aktivitetsgränser genom att erbjuda flexibla lokaler som i olika grad är tillgängliga för besökarna. Delar av strukturen är öppen och kan alltid erbjuda tak över huvudet för såväl vandrare som ungdomsgäng. Stora delar går att besöka och använda spontant medan andra delar kan bokas för mer specifika ändamål. Byggnadens utformning förhåller sig till omgivande arkitektur i form och placering och skapar på så vis en relation med det befintliga på platsen. En klassisk gårdsformation med sadeltak skjuts upp för den sluttande tomten och blir på så sätt både bekant och ny. En stor gradäng kopplar samman den upphöjda gården med stallet och utsikten över jordbruksmark och skog. / The location of Mora Kulturhus is defined by the surrounding countryside; agriculture, forest and the adjacent stable. One kilometer away flows the Mora River and on the other side it begins Järna's dense residential areas. Mora culture house is located in the southern part of Mora, the area we designed in the autumn course, and is located in the extension of the recreation area by the Mora River. With a hiking trail and cycle path, Järna, Mora and Mora Kulturhus are connected and make the place easily accessible for the residents of the areas. The main road through Mora, which connects Nykvarnsvägen in the north and road 57 in the south, gives visitors different choices towards Mora culture house. The site and Kulturhuset enable different interests to collaborate, coexist and create group identity across activity boundaries by offering flexible premises that are accessible to visitors to varying degrees. Parts of the structure are open and can always offer a roof over your head for both hikers and youth groups. Some areas of the building can be visited and used spontaneously while other parts can be booked for more specific purposes. The design of the building relates to the surrounding architecture in shape and placement and thus creates a relationship with the site. A classic farm formation with a saddle roof climbs up the sloping plot and thus becomes both familiar and new. A large grad meadow connects the elevated court yard with the stable and the view of agricultural land and forest.