Search for dissertations about: "semi-empirical modelling"

Showing result 1 - 5 of 27 swedish dissertations containing the words semi-empirical modelling.

2. 1. Modelling of Battery Electrolyte Interactions

   Author : Gustav Åvall; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Lithium-ion batteries; semi-empirical Methods.; sodium-ion batteries; ab initio molecular dynamics; electrolytes; density functional theory;

   Abstract : The rechargeable lithium-ion battery (LIB), powering our portable electronics, has transformed our everyday lives. Even though the success of the LIB there is a need for next generation batteries, due to a lack of abundant lithium and a need for greater performance and sustainable chemistries, in order to move towards a sustainable society with applications such as hybrid and electrical vehicles (EVs) and large scale energy storage for solar and wind power. READ MORE

4. 2. Solid Fuel Conversion in Dual Fluidized Bed Gasification - Modelling and Experiments

   Author : Louise Lundberg; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dual fluidized bed gasification; fuel mixing; biomass; semi-empirical modelling; char gasification rate; fuel conversion; active bed material; char reactivity;

   Abstract : Dual fluidized bed gasification (DFBG) is the initial step towards the transformation of ligno-cellulosic materials into a raw gas, which can be further upgraded into transportation fuels, such as substitute natural gas, Fischer-Tropsch diesel, dimethyl ether, and methanol. DFBG units can be operated in two distinctly different ways, depending on whether the main product is a gas (to be refined into a transportation fuel) or heat and power (with gas as a by-product). READ MORE

5. 3. Axial Mixing of Large Solids in Fluidised Beds – Modelling and Experiments

   Author : Anna Köhler; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid-dynamic down-scaling; fluidised beds; magnetic particle tracking; solids mixing; semi-empirical modelling;

   Abstract : Fluidisation is a technology commonly found wherever particulate solids are to be transported, mixed and/or reacted with a gas. At present, it is a widespread technology with applications ranging from the production of carbon nanotubes in the manufacturing industry to the conversion of solid fuels in the heat and power sector. READ MORE

6. 4. Developing semi-empirical ab initio based potentials in materials modeling

   Author : Jie Fu; Anatoly Belonoshko; Michael Odelius; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fysik; Physics;

   Abstract : Ab initiocalculation based on density function theory (DFT) is an accu-rate and efficient method for modelling material properties. It is performedby solving the Shrödinger equations with a few assumptions to obtain thephysical properties of the system. It is very computational demanding whendealing with large systems or long-time simulations. READ MORE

7. 5. Investigation of Solid Fuel Conversion in a Fluidised Bed Gasifier – Modelling and Experiments

   Author : Louise Lundberg; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; modelling; biomass; char reactivity; gasification; char conversion; fluidised bed;

   Abstract : A substantial proportion of Sweden’s greenhouse gas emissions originates from the transportation sector, and the Swedish government has set the goal that the entire Swedish vehicle fleet will be independent from fossil fuels by 2030. One of the strategies investigated to achieve this goal is biomass gasification, which is a technology that can be used to transform lignocellulosic materials into a raw gas. READ MORE