Search for dissertations about: "CFD in pipes"

Showing result 1 - 5 of 14 swedish dissertations containing the words CFD in pipes.

  2. 1. Pulsed Neutron Activation for Determination of Water Flow in Pipes

    Author : Håkan Mattsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Flowmeter; Pulsed Neutron Activation; CFD; Pipe flow; PNA;

    Abstract : In a Pulsed Neutron Activation (PNA) flowmeter neutron induced activity is used to measure water flow in pipes. The water in the pipe is bombarded with neutron pulses which introduce activity into the pipe. The activity is then transported and mixed with the flow. READ MORE

  4. 2. Steam condensation in a water pool and its effect on thermal stratification and mixing

    Author : Ignacio Gallego-Marcos; Pavel Kudinov; Walter Villanueva; Dominique Bestion; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Steam injection; EHS EMS; blowdown pipes; spargers; chugging; oscillatory bubble; CFD; condensation pool; stratification; mixing; Engineering Mechanics; Teknisk mekanik;

    Abstract : The Pressure Suppression Pool (PSP) of a Boiling Water Reactor (BWR) is a large heat sink designed to limit the containment pressure by condensing steam released from the primary coolant system. The development of thermal stratification is a safety concern since it leads to higher containment pressures than in completely mixed conditions, and can affect the performance of systems such as the emergency core cooling and containment spray, which the use PSP as a source of water. READ MORE

  5. 3. ANALYZING THE HYDRO DYNAMICS AND THE CHEMICAL REACTIONS IN PULP DIGESTER SYSTEMS USING CFD MODELLING

    Author : Bijan Pourian; Erik Dahlquist; Laszlo Fuchs; Mälardalens högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; MODELLING; SIMULATION; PULP; DIGESTER. CHEMICAL; MULTIPHASE; Cellulose and paper engineering; Cellulosa- och pappersteknik; Energy- and Environmental Engineering; energi- och miljöteknik;

    Abstract : The aim of this thesis is to use differential analysis and finite volume method (FVM) to model and analyze a continuous pulp digester in order to create a detailed picture of the flow behaviour and chemical reactions in the digester. This information will be used to optimize wood chip flow and reactions and to diagnose and avoid faults such as hang-ups and channelling. READ MORE

  6. 4. Modelling air―water flows in bottom outlets of dams

    Author : Ting Liu; James Yang; Anders Wörman; Michael Pfister; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Air pocket; Air entrainment; Bottom outlet; Critical velocity; Critical submergence; CFD; Experiment; Vortex; PIV; Two-phase air―water flow; Mark- och vattenteknik; Land and Water Resources Engineering; Civil and Architectural Engineering; Byggvetenskap;

    Abstract : If air is entrained in a bottom outlet of a dam in an uncontrolled way, the resulting air pockets may cause problems such as blowback, blowout and loss of discharge capacity. In order to provide guidance for bottom outlet design and operation, this study examines how governing parameters affect air entrainment, air-pocket transport and de-aeration and the surrounding flow structure in pipe flows. READ MORE

  7. 5. Sound generation in metal flue organ pipes: On the influence of asymmetric flue exit geometry and vibrations of the upper labium with particular emphasis on the early response

    Author : Matthias Scholz; Chalmers tekniska högskola; []
    Keywords : jet contraction; wall vibrations; CFD; jet velocity profile; tap tone; asymmetry of flue exits; operational deflection shapes; Coanda effect; yielding upper labium; modal analysis; bottom clamped cylinder; vibration measurements; metal flue organ pipes; dipole; initial jet formation;

    Abstract : Sound generation in flue organ pipes is caused by the non-linear interaction between an instable jet and a tube resonator. Our understanding of this very complex physical process is still incomplete, and there is not yet a model that can explain all details of the richness in pipe sound which can be achieved by a trained organ pipe voicer. READ MORE