Sökning: "heat wave"

Visar resultat 16 - 20 av 101 avhandlingar innehållade orden heat wave.

  1. 16. Theoretical and numerical studies of sound propagation in low-Mach-number duct flows

    Författare :Chenyang Weng; Mats Åbom; Susann Boij; Ardeshir Hanifi; Anurag Agarwal; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aeroacoustics; Acoustic wave absorption; Acoustic wave propagation; Boundary layer turbulence; DNS; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : When sound waves propagate in a duct in the presence of turbulent flow, turbulent mixing can cause attenuation of the sound waves extra to that caused by the viscothermal effects. Experiments show that compared to the viscothermal effects, this turbulent absorption becomes the dominant contribution to the sound attenuation at sufficiently low frequencies. LÄS MER

  3. 17. Topics in Simulation and Stochastic Analysis

    Författare :Mikael Signahl; Matematisk statistik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik; stochastic heat equation; stochastic wave equation; error rates; truncated Levy process; discontinuities; optimal decay rate; digital communication system;

    Sammanfattning : Paper A investigates how to simulate a differentiated mean in cases where interchanging differentiation and expectation is not allowed. Three approaches are available, finite differences (FD's), infinitesimal perturbation analysis (IPA) and the likelihood ratio score function (LRSF) method. LÄS MER

  4. 18. Approximating Stochastic Partial Differential Equations with Finite Elements: Computation and Analysis

    Författare :Andreas Petersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Lévy process; Lyapunov equation; white noise; finite element method; multilevel Monte Carlo; Monte Carlo; multiplicative noise; asymptotic mean square stability; stochastic heat equation; covariance operator; weak convergence; generalized Wiener process; numerical approximation; stochastic wave equation; Stochastic partial differential equations;

    Sammanfattning : Stochastic partial differential equations (SPDE) must be approximated in space and time to allow for the simulation of their solutions. In this thesis fully discrete approximations of such equations are considered, with an emphasis on finite element methods combined with rational semigroup approximations. LÄS MER

  5. 19. Near-Field Radiative Heat Transfer between Plasmonic Nanostructures

    Författare :Jin Dai; Min Yan; Philippe Ben-Abdallah; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fysik; Physics; Energy Technology; Energiteknik;

    Sammanfattning : Radiative heat transfer (RHT) due to coupled electromagnetic near field scan significantly exceed that dictated by Planck’s law. Understanding such phenomenon is not only of fundamental scientific interest, but also relevant to a broad range of applications especially connected to nanotechnologies. LÄS MER

  7. 20. Hydrodynamics and heat convection in channels with vibrating walls

    Författare :Fredrik Carlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In this work a combined analytical and numerical study of the non-linear effects of transverse wall vibrations on fluid flows are presented. Streaming motions and their effect on heat and mass transfer are investigated for a viscous fluid confined in an infinite channel with flexible walls. LÄS MER