Sökning: "Reynolds number effect"

Visar resultat 6 - 10 av 73 avhandlingar innehållade orden Reynolds number effect.

  1. 6. Turbulent jets in confined spaces : application in mixing ventilation: experimental and numerical studies

    Författare :Taghi Karimipanah; Mats Sandberg; H. A. Awbi; Högskolan i Gävle; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulent; wall jet; impinging jet; free jet; confinement effect; pressure; throw; experimental; numerical; corner; momentum; mixing ventilation;

    Sammanfattning : The basis of mixing ventilation is the airflow supply to the room by means of jets initiatedfrom the ventilation diffusers. To avoid the draught problem, the design of mixing ventilationmakes uses the throw term, which is defined as the distance to the supply air terminal inwhich the jet centreline mean velocity is decreased to a given value. LÄS MER

  2. 7. Experimental and Numerical Investigations of Heat Transfer related to Gas Turbine Applications

    Författare :Safeer Hussain; Värmeöverföring; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; heat transfer; obstacle; vortex generator; pin fins; endwall; Nusselt number; thermal performance; film cooling effectiveness; contouring;

    Sammanfattning : Gas turbines are broadly used in aerospace and marine propulsion and power production etc.Investigation of heat transfer in gas turbines is a long-lasting and still an active subject ofresearch due to its tremendous importance. LÄS MER

  3. 8. Turbulence Measurements in a Natural Convection Boundary Layer and a Swirling Jet

    Författare :Abolfazl Shiri; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; swirl; constant current bridge; high Rayleigh number; natural convection; Jet; cold-wire thermometry; vertical cylinder; laser Doppler anemometry; turbulent boundary layers;

    Sammanfattning : Two sets of experimental measurement were carried out on an axisymmetric swirling jet flow and a natural convection boundary layer. In the first experiment, the far field of an incompressible swirling jet, discharged into a quiescent ambient has been studied using laser Doppler anemometry. LÄS MER

  4. 9. Detailed Numerical Simulations of Turbulent Premixed Flames at Moderate and High Karlovitz Numbers

    Författare :Henning Carlsson; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct numerical simulation; Large eddy simulation; Turbulent premixed combustion; Flow-flame interaction; High Karlovitz number;

    Sammanfattning : In generally accepted and applied flamelet combustion models, a turbulent flame is mainly assumed distorted by the large-scale turbulence eddies, whereas small-scale turbulence effects on the local flamelet structures are neglected. However, in a lot of industrial applications rather high turbulent intensities are often imposed, which induce turbulence scales at ranges smaller than the flame thickness. LÄS MER

  5. 10. Experimental and numerical study of the thermal and hydraulic effect of EMC screens in radio base stations : detailed and compact models

    Författare :Raúl Antón Remírez; Björn Palm; Masud Behnia; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sub-rack; perforated plate; air cooling; 90 degrees turn; flow deistribution; CFD; measurement; Mechanical energy engineering; Mekanisk energiteknik;

    Sammanfattning : Today’s telecommunication cabinets use Electro Magnetic Compliance (EMC) screens in order to reduce electromagnetic noise that can cause some miss functions in electronic equipment. Many radio base stations (RBSs) use a 90-degree building architecture: the flow inlet is perpendicular to the EMC screen, which creates a complex flow, with a 90-degree air turn, expansions, compressions, perforated plates and PCBs. LÄS MER