Sökning: "initial conditions"

Visar resultat 36 - 40 av 976 avhandlingar innehållade orden initial conditions.

1. 36. Modeling of Initial Mold Filling in Uphill Teeming Process Considering a Trumpet

   Författare :Zhe Tan; Pär Jönsson; Robert Eriksson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gating system; uphill teeming; ingot casting; swirl blade; flow pattern; realizable k-ε model; CFD; mathematical modeling.;

   Sammanfattning : The flow pattern in the uphill teeming process has been found to be closely related to the quality of ingots and further to affect the yield of ingot production, which is crucial for the steel making process. The formation of non-metallic inclusion and entrapment of mold flux has been considered to be affected by the flow pattern in the gating system and molds by many previous researchers. LÄS MER

3. 37. Direct Numerical Simulations of Low Temperature Combustion in IC Engine Related Conditions

   Författare :Fan Zhang; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : This thesis deals with direct numerical simulation (DNS) of low temperature combustion in internal combustion engine related conditions. In particular, HCCI (homogeneous charge compression ignition), SACI (spark assisted ho-mogeneous charge compression ignition) and PPC (partially premixed charge combustion) were investigated to gain deeper understanding on the details of the combustion process. LÄS MER

4. 38. A novel implantable ultra-flexible brain machine interface. Manufacturing and initial characterisations

   Författare :Fotios Tsanakalis; Neuronano Research Center (NRC); []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Brain-Machine Interfaces; BMIs; Neural Interfaces; Electrodes;

   Sammanfattning : This thesis describes for the very first time the development of a miniaturized neural interface which is flexible in three dimensions (3D) to enable it to follow the brain movements with minimal dislocation. Both the design rationale and the material choice for the electrodes aim to develop interfaces that minimize the damage and/or the irritation of the tissue during and after the implantation. LÄS MER

5. 39. The role of particles on initial atmospheric corrosion of copper and zinc : lateral distribution, secondary spreading and CO2-/SO2-influence

   Författare :Zhuo Yuan Chen; Christofer Leygraf; Jan-Erik Svensson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmospheric corrosion; copper; zinc; NaCl particles; NH4 2SO4; Materials chemistry; Materialkemi;

   Sammanfattning : The role of sodium chloride (NaCl) particles and ammonium sulfate ((NH4)2SO4) particles on the initial atmospheric corrosion of copper and zinc was investigated under in situ and ex situ conditions using microgravimetry, FTIR spectroscopy, ion chromatography, scanning electron microscopy with x-ray microanalysis and the scanning Kelvin probe. For the first time, in situ infrared spectra were collected on a micron level during particle induced atmospheric corrosion using a recently developed experimental set-up for in situ FTIR microspectroscopy. LÄS MER

7. 40. A Study of the Initial Mould Filling during Up-hill Ingot Casting

   Författare :Line Hallgren; Pär Jönsson; Anders Tilliander; Seppo Louhenkilpi; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; swirling flow; up-hill teeming; nozzle; casting; fluid flow; modelling; CFD; LDA; swirl; ingot casting; filling; red eye;

   Sammanfattning : The fluid flow in the mould during up-hill teeming is of great importance for the quality of the cast ingot and thereby the quality of the final steel products. At the early stage of the filling of an up-hill teeming mould, liquid steel flows with a high velocity from the runner into the mould. LÄS MER