Essays about: "värmeledningsförmåga"

Showing result 1 - 5 of 28 essays containing the word värmeledningsförmåga.

  1. 1. Calibration of the Measurement System for Methane Pyrolysis in Rocket Nozzle Cooling Channels

    University essay from KTH/Skolan för industriell teknik och management (ITM)

    Author : Jennifer Ly; [2023]
    Keywords : Correlational method; gas analysis; real time measurements; speed of sound; thermal conductivity; methane pyrolysis; rocket nozzle cooling; Korrelationsmetod; gasanalys; mätningar i real tid; ljudhastighet; värmeledningsförmåga; metanpyrolys; kylning av raketmunstycken iv;

    Abstract : Methane-based rocket propellant is gaining traction as a green technology with advantages in sustainability, cost-effectiveness, and performance. However, under high temperatures found in rocket nozzle cooling channels, methane can undergo thermal decomposition known as methane pyrolysis, resulting in the generation of hydrogen and solid carbon. READ MORE

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

    University essay from KTH/Fysik

    Author : Daniel Karlsson; [2023]
    Keywords : 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;

    Abstract : 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). READ MORE

  4. 3. Numerical Modelling of a Packed Bed Thermal Energy Storage for Applications in a Carnot Battery : KTH Thesis Report

    University essay from KTH/Skolan för industriell teknik och management (ITM)

    Author : Gabriel Juul; [2023]
    Keywords : Thermal energy storage; Carnot battery; sand; packed bed; granular medium; porous medium; effective medium technique; effective thermal conductivity; paramedic study; 3D model; COMSOL; numerical modelling; Lagring av värmeenergi; Carnot-batteri; sand; packad bädd; granulärt medium; poröst medium; effektiv mediumteknik; effektiv värmeledningsförmåga; parametrisk studie; 3D-modell; COMSOL; numerisk modellering;

    Abstract : This thesis explores the heat transfer characteristics of a packed bed thermal energy storage device through the development of a 3D model in COMSOL Multiphysics. The model is based on a laboratory-scale device consisting of an aluminum box filled with sand, which acts as the thermal storage medium. READ MORE

  5. 4. Application of ring statistics to characterise graphitisation of carbon fiber heat shields under atmospheric re-entry conditions

    University essay from KTH/Lättkonstruktioner, marina system, flyg- och rymdteknik, rörelsemekanik

    Author : Hamish Keay; [2023]
    Keywords : Aerospace; Heat shields; Re-entry; Graphitisation; Carbon fiber; Carbon phenolic; Ring statistics; Graph theory; Molecular Dynamics; återinträde; grafitisering; kolfiber; kolfenol; ringstatistik; grafteori; molekylär dynamik;

    Abstract : Carbon fibers submitted to high temperatures (>2000 °C) experience a permanent increasein their thermal conductivity. This change has been attributed to a change in the molecularstructure due to graphitisation. READ MORE

  6. 5. Thermally insulating carbon foams from carbonized kraft lignin

    University essay from KTH/Fiber- och polymerteknologi

    Author : Isabelle Hernodh Svantesson; [2021]
    Keywords : Carbon foams; thermal insulation; kraft lignin; carbonization; thermal conductivity; Kolskum; värmeisolering; kraftlignin; karbonisering; värmeledningsförmåga;

    Abstract : Kolmaterial, såsom kolfibrer och kolskum, används som värmeisolatorer i applikationer vid höga temperaturer. För närvarande härleds dessa material från fossilbaserade källor, vilket tyder på ett behov av att hitta alternativa kandidater baserade på förnybara källor. READ MORE