Sökning: "annular flow"

Visar resultat 1 - 5 av 43 avhandlingar innehållade orden annular flow.

1. 1. Numerical Studies of Flow and AssociatedLosses in the Exhaust Port of a Diesel Engine

   Författare :Yue Wang; Laszlo Fuchs; Mihai Mihaescu; Angelo Onorati; KTH; []
   Nyckelord :Internal Combustion Engine; Exhaust flow; Exhaust Valve; Exhaust Port; Large Eddy Simulation; Valve and Piston Motion; Total Pressure Losses; Energy Losses; Discharge coefficient; Flow Losses; Flow structures; Air Flow Bench; Engine-like Conditions; SRA - Energy; SRA - Energi;

   Sammanfattning : In the last decades, the focus of internal combustion engine development has moved towards more efficient and less pollutant engines. In a Diesel engine, approximately 30-40% of the energy provided by combustion is lost through the exhaust gases. The exhaust gases are hot and therefore rich of energy. LÄS MER

3. 2. Measurements of Film Flow Rate in Heated Tubes with Various Axial Power Distributions

   Författare :Carl Adamsson; Henryk Anglart; Bengt Sundén; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; film flow; film thickness; dryout; power distribution; annular flow; Atomic physics; Atomfysik;

   Sammanfattning : Measurements of film mass flow rate for annular, diabatic steam-water flow in tubes are presented. The measurements were carried out with four axial power distributions and at several axial positions at conditions typical for boiling water reactors, i.e. 7 MPa pressure and total mass flux in a range from 750 to 1750 kg/m2s. LÄS MER

4. 3. Aerodynamic Investigations of a High Pressure Turbine Vane with Leading Edge Contouring at Endwall in a Transonic Annular Sector Cascade

   Författare :Ranjan Saha; Torsten Fransson; Markus Jöcker; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high pressure turbine; secondary flow; leading edge contouring; endwall; experimental investigations; losses; flow field; hub cooling flow; högtrycksturbinen sekundärströmning; framkantsmodifiering; ändvägg; experimentell undersökning; förluster; strömningsfält; filmkylning av inre platform;

   Sammanfattning : Efficiency improvement is an important aspect to reduce the use of fossil-based fuel in order to achieve a sustainable future. Gas turbines are mainly fossil-fuel based turbomachines, and, therefore, efficiency improvement is still the subject of many on-going research activities in the gas turbine community. LÄS MER

5. 4. Flow Boiling Heat Transfer in Single Vertical Channels of Small Diameter

   Författare :Claudi Martin Callizo; Björn Palm; Predrag Hrnjak; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microchannel; heat exchanger; heat transfer; flow boiling; flow patterns; onset of nucleate boiling; dryout; critical heat flux; Mechanical and thermal engineering; Mekanisk och termisk energiteknik;

   Sammanfattning : Microchannel heat exchangers present many advantages, such as reduced size, high thermal efficiency and low fluid inventory; and are increasingly being used for heat transfer in a wide variety of applications including heat pumps, automotive air conditioners and for cooling of electronics.However, the fundamentals of fluid flow and heat transfer in microscalegeometries are not yet fully understood. LÄS MER

7. 5. Experimental Study and Modelling of Spacer Grid Influence on Flow in Nuclear Fuel Assemblies

   Författare :Diana Caraghiaur Garrido; Henryk Anglart; Dominique Bestion; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spacer grid influence; annular flow; deposition; Lagrangian Particle Tracking;

   Sammanfattning : The work is focused on experimental study and modelling of spacer grid influence on single- and two-phase flow. In the experimental study a mock-up of a realistic fuel bundle with five spacer grids of thin plate spring construction was investigated. A special pressure measuring technique was used to measure pressure distribution inside the spacer. LÄS MER