Sökning: "near-field effect"

Visar resultat 11 - 15 av 24 avhandlingar innehållade orden near-field effect.

1. 11. Experimental study of passive scalar mixing in swirling jet flows

   Författare :Ramis Örlü; Henrik Alfredsson; Peter Johansson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; swirling jet; turbulence; passive scalar; mixing; hot-wire anemometry; cold-wire; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : Despite its importance in various industrial applications there is still a lack of experimental studies on the dynamic and thermal field of swirling jets in the near-field region. The present study is an attempt to close this lack and provide new insights on the effect of rotation on the turbulent mixing of a passive scalar, on turbulence (joint) statistics as well as the turbulence structure. LÄS MER

3. 12. Numerical and experimental study of confluent jets supply device with variable airflow

   Författare :Harald Andersson; Bahram Moshfegh; Mathias Cehlin; Fredrik Karlsson; Högskolan i Gävle; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Confluent jets; Air distribution system; Air supply device; Ventilation performance; Indoor air quality; Thermal comfort; Experimental study; Laser Doppler Anemometry LDA ; Computational fluid dynamics CFD ; Shear stress transport SST k – ω ; confluent jets; luftdistributionssystem; tilluftsdon; ventilationsprestanda; inomhusluftkvalitet; termisk komfort; experimentell studie; Laser-Doppler-anemometri LDA ; Computational fluid dynamics CFD ; turbulens model SST k – ω ; Hållbar stadsutveckling; Sustainable Urban Development;

   Sammanfattning : In recent years, application of confluent jets for design of ventilation supply devices has been studied. Similarly, numerus studies have been made on the potential and application of variable air volume (VAV) in order to reduce the energy demand of ventilation systems. LÄS MER

4. 13. Sustainable Water Quality Monitoring for Developing Countries in the Context of Mining : Monitoring systems and modelling

   Författare :Clemencio Nhantumbo; Avdelningen för Teknisk vattenresurslära; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Water Quality; Monitoring systems; Modelling; pH and alkalinity;

   Sammanfattning : Mining, seen as a source of revenue in most developing countries, threatens seriously the environment. Mining impacts the water quality and one of the main problems of mining is acid mine drainage. Low pH and high concentration of heavy metals characterize acid mine drainage. LÄS MER

5. 14. Mass Transport via Thermoplasmonics

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

   Sammanfattning : When a metallic nanoparticle is illuminated with light under resonant conditions, the free electron gas oscillates in such a way that substantial amplification of the local electric field amplitude is achieved – this is known as a plasmonic resonance. This resonance enhances both the optical scattering as well as absorption. LÄS MER

7. 15. Experimental studies in jet flows and zero pressure-gradient turbulent boundary layers

   Författare :Ramis Örlü; P. Henrik Alfredsson; Tim B. Nickels; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Axisymmetric jet; swirling jet; coaxial jet; heated jet; zero pressuregradient turbulent boundary layer; wall-bounded turbulent flows; overlap region; passive scalar mixing; hot-wire anemometry; spatial resolution.; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : This thesis deals with the description and development of two classical turbulent shear flows, namely free jet and flat plate turbulent boundary layer flows. In both cases new experimental data has been obtained and in the latter case comparisons are also made with data obtained from data bases, both of experimental and numerical origin. LÄS MER