Sökning: "Boltzmann transport equation"

Hittade 4 uppsatser innehållade orden Boltzmann transport equation.

  1. 1. First principles investigation of the thermal conductivity of Zr, ZrC, and ZrN

    Master-uppsats, KTH/Fysik

    Författare :Daniel Karlsson; [2023]
    Nyckelord :Electron-phonon interaction; Density functional theory; Boltzmann transport equation; first-principles; thermal conductivity; electrical resistivity; Abinit; Phono3py; Elektron-fononväxelverkan; täthetsfunktionalteori; Boltzmanns transportekvation; värmeledningsförmåga; elektrisk resistivitet; Abinit; Phono3py;

    Sammanfattning : The thermal conductivity and electrical resistivity of Zr, ZrC, and ZrN were calculated using first-principles density functional theory (DFT) and the Boltzmann transport equation. The electron-phonon scattering was modeled via the self-energy relaxation time approximation (SERTA), and the phonon-phonon scattering via the analogous single-mode relaxation time approximation (SMRTA). LÄS MER

  3. 2. Coulomb drag in parallel nanowires

    Master-uppsats, Lunds universitet/Fasta tillståndets fysik; Lunds universitet/Fysiska institutionen

    Författare :David Dai; [2020]
    Nyckelord :Coulomb drag; nanowire; Physics and Astronomy;

    Sammanfattning : In this project the transport phenomenon Coulomb drag is studied in a 1D system comprised of two nanowires in parallel. Specifically, a driving current across the active wire generated a drag current in the passive wire, and we studied how Coulomb drag influenced both the driving and drag currents. LÄS MER

  4. 3. Non-Thermal Modeling Of Energy Propagation Carried By Phonons and Magnons

    Kandidat-uppsats,

    Författare :David Dahlgren; Amela Mehic; [2019]
    Nyckelord :phonon; magnon; Boltzmann transport equation; Heat transport; Atom;

    Sammanfattning : Heat transport by phonons and magnons in crystals due to a local perturbation in temperature is described by the Boltzmann transport equation. In this project a one phonon one magnon system was studied in a one dimensional rod with reflective boundaries. Using the splitting algorithm the problem was reduced to a transport and collision term. LÄS MER

  5. 4. Approximating general relativistic effects in Newtonian hydrodynamic supernova simulations

    Kandidat-uppsats, Stockholms universitet/Institutionen för astronomi

    Författare :Elvira Granqvist; [2019]
    Nyckelord :;

    Sammanfattning : In this research, the validity of using an effective potential to approximate general relativistic effects in an otherwise Newtonian setting was investigated, by making simulations of core collapse supernovae on one hand in full general relativity, and on the other hand in said Newtonian setting. This was done for a mass range covering progenitors of 12 − 60 solar masses; a much wider mass range than has been used in earlier research, that also includes progenitors that form black holes. LÄS MER