Sökning: "free jet"

Visar resultat 21 - 25 av 52 avhandlingar innehållade orden free jet.

1. 21. A study of turbulence and scalar mixing in a wall-jet using direct numerical simulation

   Författare :Daniel Ahlman; Arne V. Johansson; Lars-Erik Eriksson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningmekanik; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : Direct numerical simulation is used to study the dynamics and mixing in a turbulent plane wall-jet. The investigation is undertaken in order to extend the knowledge base of the influence of the wall on turbulent dynamics and mixing. The mixing statistics produced can also be used to evaluate and develop models for mixing and combustion. LÄS MER

3. 22. Aerodynamic Design and Optimization of Intermediate Ducts for High By-pass Ratio Jet Engines

   Författare :Fredrik Wallin; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Intermediate transition ducts; vortex generators; S-shaped ducts; response surface methodology; source term model; optimization;

   Sammanfattning : Demands on improved efficiency and reduced noise levels cause a strive toward high by-pass ratio commercial aero engines. This results in multi-spool aero engines with small high-pressure ratio cores and large fans. The low-pressure system has a lower rotational speed and a larger radius than the high-pressure core system. LÄS MER

4. 23. Numerical investigation of the turbulent flow and heat transfer around a heated cube cooled by and impinging jet in a cross-flow

   Författare :Daniel Rundström; Bahram Moshfegh; Sasa Kenjers; Linköpings universitet; []
   Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : Impinging jets are used for many industrial applications where high heat and mass transfer rates are required. The electronic industry is one of the fastest growing industries and applications of cooling technology in this field are of considerable importance. Forced channel flow is frequently used as a cooling technique. LÄS MER

5. 24. Study on Metallic Melt Coolant Interactions and Debris Bed Formation in a Water Pool

   Författare :Yan Xiang; Weimin Ma; Sevostian Bechta; Andrei A. Komlev; Michael Buck; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Severe accident; fuel coolant interactions; metallic melt; jet fragmentation; debris bed; CLSVOF.; Svåra haverier; interaktioner mellan bränsle och kylmedel; metallsmälta; jetfragmentering; grusbädd; CLSVOF; Kärnenergiteknik; Nuclear Engineering;

   Sammanfattning : To assess corium coolability during severe accidents of LWR, significant number of studies have been conducted previously to investigate the characteristics of debris beds formed from FCI due to fragmentation of molten corium and settlement of the fragments in a water pool. However, their focus has been placed on the oxidic component (UO2/ZrO2) of corium, while little attention has been paid to the debris bed formation due to FCI of the metallic component (Zr/Fe) of corium. LÄS MER

7. 25. Experimental Investigation of Cavitation-Bubble-Induced Atomization

   Författare :Jiayi Zhou; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cavitation bubble; liquid atomization; shadowgraph;

   Sammanfattning : Improving the efficiency and lowering the emissions of internal combustion engines (ICE) has been drawing increased attention because climate change caused by greenhouse gases and the need to reduce emission harmful to human health, and stricter legislation on the emissions from liquid-fueled transportation is implemented. Design of the liquid fuel atomizer, which atomizes the fuel delivered into the combustion chamber by the fuel injection system, is important because a good atomization, which facilitates the evaporation of fuel and improves the fuel-air mixture, leads to higher efficiency and lower emissions of ICE. LÄS MER