Sökning: "cooling flow"

Visar resultat 21 - 25 av 213 avhandlingar innehållade orden cooling flow.

1. 21. Modelling of stably-stratified, convective and transitional atmospheric boundary layers using the explicit algebraic Reynolds-stress model

   Författare :Velibor Zeli; Gert Brethouwer; Arne V. Johansson; Stefan Wallin; Bert Holtslag; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmospheric turbulence; convective atmosphere; Reynolds-stress model; stably-stratified atmosphere; transitional atmosphere; Engineering Mechanics; Teknisk mekanik;

   Sammanfattning : The atmospheric boundary layer (ABL) is in continuous turbulent motion. The heating and cooling of the Earth’s surface drives mechanic and thermodynamic processes in the ABL through enhancing and damping of atmospheric turbulence. The surface forcing has a profound effect on the diurnal cycle of temperature,wind and related variables in the ABL. LÄS MER

3. 22. Wheel Modelling and Cooling Flow Effects on Car Aerodynamics

   Författare :Teddy Hobeika; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : In recent years, the automotive industry has focused on computer simulations as an alternative to physical testing. This allows for early vehicle optimization, short turn around times, and significant cost savings. LÄS MER

4. 23. Turbulence Modelling of Flows Related to Wall-Cooling Applications

   Författare :Stefan Jansson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; low-Reynolds number models; second-order-moment closures; turbulent heat transfer; two-equation models; film-cooling; near-wall models; turbulence modelling;

   Sammanfattning : Engineering flows are generally characterised by complex strain field and turbulence structure arising from a combination of shear, curvature, separation and recirculation etc. Under such flow conditions, transport by turbulent velocity fluctuations can make a significant contribution to the transport of momentum, heat and mass. LÄS MER

5. 24. Hardening of Carbon Steel by Water Impinging Jet Quenching Technique : Differential Cooling of Steel Sheets and Quenching of Cylindrical Bars

   Författare :Pavel Romanov; Mattias Calmunger; Bahram Moshfegh; Viktor Norman; Ru Peng; Peter Hedström; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Differential cooling; Impinging jet quenching; Microstructure gradient; Hardening;

   Sammanfattning : Austenitization followed by quenching is a well-known conventional heat-treating procedure which is widely used on carbon steels with the aim to obtain high strength in as-quenched condition. Such quenching is usually done by immersing a steel product into the cooling medium which provides a uniform cooling of the surface. LÄS MER

7. 25. Preliminary Design Investigations for the Selection of Optimum Reaction Degree for 1st Stage of a High Pressure Gas Turbine

   Författare :Hina Noor; Torsten Fransson; Konstantinos G. Kyprianidis; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 1D design; aerodynamic design parameters; flow kinematic; thermodynamics; rotor inlet temperature; cooled turbine; reaction degree; flow coefficient; stage loading;

   Sammanfattning : One-dimensional (1D) turbine design calculation phase requires a handful of input data and choice of design parameters to provide the blade flow path geometry along with the flow kinematics and thermodynamics properties at the blade mid-span. The choice of important aerodynamics design parameters namely reaction degree, nozzle guide vane NGV exit flow angle or flow coefficient and stage loading defines the mid-span flow velocity triangles. LÄS MER