New computer software for defining the three-dimensional geometry for a centrifu- gal compressor impeller

In this thesis, a computer software for defining the geometry for a centrifugal compressor impeller is designed and implemented. The project is done under the supervision of Laboratory of Fluid Dynamics in Lappeenranta University of Technology. This thesis is similar to the thesis written by Tomi Putus (2009) in which a centrifugal compressor impeller flow channel is researched and commonly used design practices are reviewed. Putus wrote a computer software which can be used to define impeller’s three-dimensional geometry based on the basic geometrical dimensions given by a preliminary design. The software designed in this thesis is almost similar but it uses a different programming language (C++) and a different way to define the shape of the impeller meridional projection.

Kolmiulotteisen kulttuuriperintökohteen digitointiprosessi

Dokumenttien, valokuvien, videon ja äänen digitoinnin rinnalle on syntynyt tarve digitoida kohteita kolmiulotteisesti. Kolmiulotteinen digitointi asettaa digitoinnille uusia haasteita, sillä kohteista on kerättävissä hyvin paljon dataa. Digitointia varten tarvitaan siis prosessi jossa määritellään mitä kohteesta tulee digitoida ja miten tämä tehdään, jotta työ pystytään tekemään järkevässä ajassa järkevin kustannuksin. Työssä tutkittiin kirjallisuustutkimuksen ja kolmen digitointikohteen kautta miten prosessi tulisi muodostaa. Lopputuloksena muotoutui prosessimalli, jossa vaiheittain toteutetaan erilaisten työryhmien kanssa digitointisuunnitelma, laitevalinnat sekä digitointityö. Prosessin avulla digitointihankkeen suunnittelu helpottuu ja kustannusten sekä projektin etenemisen esittely asiakkaalle on yksinkertaista.

Sotilasjohtaja ja valta : analyysi vallan kolmessa ulottuvuudessa

Sanaan valta liittyy usein kielteisiä mielleyhtymiä. Vallan sanotaan esimerkiksi turmelevan, alistavan ja pakottavan. Voidaan kuitenkin todeta, että valtaa tarvitaan, jotta ihmiset saadaan toimimaan yhdessä yhteisten tavoitteiden saavuttamiseksi. Valta liittyy keskeisesti organisaatioiden toimintaan. Organisaatioita ei voi ymmärtää ymmärtämättä niiden valtarakenteita.

Modelling of calciner in post-combustion carbon capture process

Climate change has given an impetus to research and developed new technologies to reduce significantly carbon dioxide emissions in energy production in the developed countries. The major pollution source, fossil fuels, will be used as an energy source for many decades, which provides the demand for carbon capture and storage technologies. Over recent years many new technologies has been developed and one of the most promising is calcium-looping in post-combustion carbon capture process, which use carbonation-calcination cycle to capture carbon dioxide from the flue gas of a combustion process. First pilot plant for calcium-looping process has been built in Oviedo, Spain. In this study, a three-dimensional model has been created for the calciner, which is one of the two fluidized bed reactors needed for the process. The calciner is a regenerator where the captured carbon dioxide is removed from the calcium material and then collected after the reactor. Thesis concentrates in creating the calciner 3D-model frame with CFB3D-program and testing the model with two different example cases. Used input parameters and calciner geometry are Oviedo pilot plant design parameters. The calculation results give information about the process and show that pilot plant calciner should perform as planned. This Master’s Thesis is done in participation to EU FP7 project CaOling.

Validation of a 3D model for oxygen combustion in a circulating fluidized bed

In this thesis, a model called CFB3D is validated for oxygen combustion in circulating fluidized bed boiler. The first part of the work consists of literature review in which circulating fluidized bed and oxygen combustion technologies are studied. In addition, the modeling of circulating fluidized bed furnaces is discussed and currently available industrial scale three-dimensional furnace models are presented. The main features of CFB3D model are presented along with the theories and equations related to the model parameters used in this work. The second part of this work consists of the actual research and modeling work including measurements, model setup, and modeling results. The objectives of this thesis is to study how well CFB3D model works with oxygen combustion compared to air combustion in circulating fluidized bed boiler and what model parameters need to be adjusted when changing from air to oxygen combustion. The study is performed by modeling two air combustion cases and two oxygen combustion cases with comparable boiler loads. The cases are measured at Ciuden 30 MWth Flexi-Burn demonstration plant in April 2012. The modeled furnace temperatures match with the measurements as well in oxygen combustion cases as in air combustion cases but the modeled gas concentrations differ from the measurements clearly more in oxygen combustion cases. However, the same model parameters are optimal for both air and oxygen combustion cases. When the boiler load is changed, some combustion and heat transfer related model parameters need to be adjusted. To improve the accuracy of modeling results, better flow dynamics model should be developed in the CFB3D model. Additionally, more measurements are needed from the lower furnace to find the best model parameters for each case. The validation work needs to be continued in order to improve the modeling results and model predictability.

Remote sensing for three-dimensional modelling of hydromorphology

Successful management of rivers requires an understanding of the fluvial processes that govern them. This, in turn cannot be achieved without a means of quantifying their geomorphology and hydrology and the spatio-temporal interactions between them, that is, their hydromorphology. For a long time, it has been laborious and time-consuming to measure river topography, especially in the submerged part of the channel. The measurement of the flow field has been challenging as well, and hence, such measurements have long been sparse in natural environments. Technological advancements in the field of remote sensing in the recent years have opened up new possibilities for capturing synoptic information on river environments. This thesis presents new developments in fluvial remote sensing of both topography and water flow. A set of close-range remote sensing methods is employed to eventually construct a high-resolution unified empirical hydromorphological model, that is, river channel and floodplain topography and three-dimensional areal flow field. Empirical as well as hydraulic theory-based optical remote sensing methods are tested and evaluated using normal colour aerial photographs and sonar calibration and reference measurements on a rocky-bed sub-Arctic river. The empirical optical bathymetry model is developed further by the introduction of a deep-water radiance parameter estimation algorithm that extends the field of application of the model to shallow streams. The effect of this parameter on the model is also assessed in a study of a sandy-bed sub-Arctic river using close-range high-resolution aerial photography, presenting one of the first examples of fluvial bathymetry modelling from unmanned aerial vehicles (UAV). Further close-range remote sensing methods are added to complete the topography integrating the river bed with the floodplain to create a seamless high-resolution topography. Boat- cart- and backpack-based mobile laser scanning (MLS) are used to measure the topography of the dry part of the channel at a high resolution and accuracy. Multitemporal MLS is evaluated along with UAV-based photogrammetry against terrestrial laser scanning reference data and merged with UAV-based bathymetry to create a two-year series of seamless digital terrain models. These allow the evaluation of the methodology for conducting high-resolution change analysis of the entire channel. The remote sensing based model of hydromorphology is completed by a new methodology for mapping the flow field in 3D. An acoustic Doppler current profiler (ADCP) is deployed on a remote-controlled boat with a survey-grade global navigation satellite system (GNSS) receiver, allowing the positioning of the areally sampled 3D flow vectors in 3D space as a point cloud and its interpolation into a 3D matrix allows a quantitative volumetric flow analysis. Multitemporal areal 3D flow field data show the evolution of the flow field during a snow-melt flood event. The combination of the underwater and dry topography with the flow field yields a compete model of river hydromorphology at the reach scale.

Peeps into fairyland : a panorama picture book of fairy stories

Kansikuva, kolmiulotteinen pop-up-kirja

Operoitujen painehaavojen jälkikorjaustarve

Tämän tutkimuksen tarkoituksena oli tutkia TYKS:ssa vuosina 2008-2012 operatiivisesti hoidettujen painehaavapotilaiden jälkikorjausoperaatioiden tarvetta. Tavoitteena oli selvittää, kuinka monen potilaan kohdalla on päädytty jälkikorjaukseen ja mitkä riskitekijät jälkikorjaustarpeeseen vaikuttavat. Painehaava eli makuuhaava on krooninen haava, jonka aiheuttaa ihoon kohdistuva paine ja hankaus. Painehaava syntyy tavallisimmin kohtiin, joihin kuormitus kohdistuu potilaan istuessa tai maatessa. Tyypillisesti haavat muodostuvat luisten ulokkeiden kohdalle. Painehaavoja hoidetaan konservatiivisesti sekä operatiivisesti. Konservatiiviseen hoitoon kuuluu paineen poisto hankaavan alueen kohdalta sekä haavan paikallishoito. Operatiiviseen hoitoon kuuluu revisio ja rekonstruktio. Tutkimukseen valittiin TYKS plastiikkakirurgian klinikassa rekonstruktiivisella kirurgialla hoidetut painehaavapotilaat vuosina 2008 – 2014, ja potilaita oli yhteensä 45. Tutkimuksessa todettiin, että 26,7 % TYKS:ssa operoiduista painehaavapotilaista päätyi jälkitoimenpiteeseen. Jälkitoimenpideriskiin vaikutti primaaritoimenpiteessä käytetty rekonstruktiomenetelmä. Potilaan päihdetausta näytti olevan riskitekijä jälkitoimenpiteille, mutta se yhdistettiin riskiin sekundaarisesti valitun rekonstruktiomenetelmän kautta. Operoitujen potilaiden iän, tupakointitaustan, selkäydinvamman, MS-taudin, haavassa kasvavan multiresistentin bakteerin tai primaarihaavan operoineen kirurgin ei todettu vaikuttavan jälkitoimenpideriskiin.