Search for dissertations about: "pipe flow"

Showing result 1 - 5 of 125 swedish dissertations containing the words pipe flow.

  1. 1. Stability of plane Couette flow and pipe Poiseuille flow

    Author : Per-Olov Åsén; Gunilla Kreiss; Jonathan Goodman; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydrodynamic stability; plane Couette flow; pipe Poiseuille flow; direct numerical simulations; resolvent; Fluid mechanics; Strömningsmekanik;

    Abstract : This thesis concerns the stability of plane Couette flow and pipe Poiseuille flow in three space dimensions. The mathematical model for both flows is the incompressible Navier--Stokes equations. Both analytical and numerical techniques are used. We present new results for the resolvent corresponding to both flows. READ MORE

  2. 2. A Study of Using Pulsed Neutron Activation for Accurate Measurements of Water Flow in Pipes

    Author : Per Lindén; Chalmers University of Technology; []
    Keywords : pulsed neutron activation; turbulent flow; neural networks; pipe flow; flow measurements; eddy diffusion; time averaging;

    Abstract : The objectives of this work were 1) to investigate the performance of the pulsed neutron activation (PNA) method for determination of mass flow of water in pipes, and 2) to improve the accuracy such that an error less than 1% become possible with the PNA method. The ultimate purpose is to develop this method into a high-accuracy portable and non-intrusive flow-meter that easily can be used as a calibration tool at a number of field applications, e. READ MORE

  3. 3. Experimental study of turbulent flows through pipe bends

    Author : Athanasia Kalpakli; P. Henrik Alfredsson; Ramis Örlü; Christoph Brücker; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent flow; swirl; pulsation; pipe bend; hot-wire anemometry; cold-wire anemometry; laser Doppler velocimetry; stereoscopic particle image velocimetry.;

    Abstract : This thesis deals with turbulent flows in 90 degree curved pipes of circular cross-section. The flow cases investigated experimentally are turbulent flow with and without an additional motion, swirling or pulsating, superposed on the primary flow. READ MORE

  4. 4. Distributed thermal response tests : New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes

    Author : José Acuña; Björn Palm; Jeffrey Spitler; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; Borehole heat exchangers; Distributed Thermal Response Test; Ground Source Heat Pumps; Coaxial; U-pipe; Multi-pipe; Pipe-in-pipe; Multi-chamber; Groundwater; Thermosyphon; SRA - Energy; SRA - Energi;

    Abstract : U-pipe Borehole Heat Exchangers (BHE) are widely used today in ground source heating and cooling systems in spite of their less than optimal performance. This thesis provides a better understanding on the function of U-pipe BHEs and Investigates alternative methods to reduce the temperature difference between the circulating fluid and the borehole wall, including one thermosyphon and three different types of coaxial BHEs. READ MORE

  5. 5. Studies of sound generation and propagation in flow ducts

    Author : Fabrice Ducret; Mats Åbom; Andy Moorhouse; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; two-port; plane wave; HVAC system; tailpipe; exhaust system; flexible duct; pipe; reflection coefficient; impedance; flow noise; vorticity; damping; scaling laws; impedance; transmission loss; perforated plate; slit; non linearity; Acoustics; Akustik;

    Abstract : This thesis contains three papers investigating problems of interest for noise control in ducts. The first part of this thesis treats the sound propagation in rectangular ducts with flexible walls. Various experimental techniques are performed to measure the internal sound propagation and radiation to the surrounding. READ MORE