Search for dissertations about: "extensional"

Showing result 1 - 5 of 60 swedish dissertations containing the word extensional.

  2. 1. Extensional rheometry through hyperbolic contraction

    Author : Magda Nyström; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dysphagia; Boger fluid; hyperbolic contraction flow; extensional rheology; axisymmetric contraction–expansion; numerical simulation; Viscoelastic fluid; pressure drop;

    Abstract : To understand fluid rheology, properties such as consistency and viscosity are determined in both shear and extensional flow. Many commonly-used materials and formulations exhibit complex rheological properties and in order to determine the behaviour as well as predict and govern their properties, effective and reliable characterisation of these fluids is important. READ MORE

  4. 2. Evaluation of a Measuring System for Determining Extensional Properties

    Author : Magda Nyström; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LPTT-model; Viscoelastic fluid; Boger fluid; numerical simulation; FENE-CR model; extensional rheology; White-Metzner model; hyperbolic contraction flow;

    Abstract : Effective and reliable characterisations of fluids are important to gain knowledge of thebehaviour and to govern the properties of a fluid. Since food products often are non-Newtonian, viscoelastic liquids, the characterisation becomes more complicated. READ MORE

  5. 3. Transmission of waves through elastic and viscoelastic junctions

    Author : Tomas Nygren; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Wave; elastic; viscoelastic; extensional; characteristic impedance; junction; transmission; reflection; dissipation; optimisation; Materialvetenskap; Materials science; Teknisk materialvetenskap; Solid Mechanics; hållfasthetslära;

    Abstract : Transmission of extensional waves through elastic and viscoelastic junctions between elastic and collinear bars have been studied theoretically and experimentally. The models used can be interpreted also for other types of waves (e.g. dilatational waves, shear waves, electromagnetic waves) and systems. READ MORE

  6. 4. Estimation of state and identification of complex modulus based on measurements om a bar traversed by waves

    Author : Lars Hillström; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Wave; extensional; flexural; bar; rod; beam; elastic; viscoelastic; complex modulus; non-parametric; parametric; standard deviation; Materialvetenskap; Materials science; Teknisk materialvetenskap; Solid Mechanics; hållfasthetslära;

    Abstract : Estimation of state and identification of complex modulus based on measurements on non-uniform rods and beams have been studied theoretically and experimentally. Two principal cases were studied. In the first case, the material properties are fully known and the state at a section is to be estimated. READ MORE

  7. 5. Piezoelectric Generation and Damping of Extensional Waves in Bars

    Author : Anders Jansson; Bengt Lundberg; Urmas Valdek; Peter Olsson; Uppsala universitet; []
    Keywords : Technology; Piezoelectric; wave; generation; damping; bar; TEKNIKVETENSKAP;

    Abstract : This thesis focuses on the electromechanical processes of generation and damping of transient waves in bars with attached piezoelectric members. In particular, the influence of amplifier and electrical circuitry on the mechanical waves is of interest. READ MORE