Sökning: "air-water flow"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden air-water flow.

1. 1. Estimating the Air-Water Gas Transfer Velocity during Low Wind Conditions

   Författare :Sam Fredriksson; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Air.sea gas exchange; Turbulence; Heat flux; Natural convection; Shear; Direct numerical simulations; Gas transfer velocity; IR; Flux-chambers;

   Sammanfattning : The abundances of atmospheric carbon dioxide, CO2, and methane, CH4, are increasing. These increases affect e.g., the global carbon cycle and the climate both regionally and globally. LÄS MER

3. 2. Advanced power cycles with mixture as the working fluid

   Författare :Maria Jonsson; KTH; []
   Nyckelord :power cycle; mixture working fluid; Kalina cycle; ammonia-water mixture; reciprocating internal combustion engine; bottoming cycle; gas turbine; evaporative gas turbine; air-water mixture; exergy;

   Sammanfattning : The world demand for electrical power increasescontinuously, requiring efficient and low-cost methods forpower generation. This thesis investigates two advanced powercycles with mixtures as the working fluid: the Kalina cycle,alternatively called the ammonia-water cycle, and theevaporative gas turbine cycle. LÄS MER

4. 3. Air-pocket transport in conjunction with bottom-outlet conduits for dams

   Författare :Ting Liu; Anders Wörman; James Yang; Staffan Lundström; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Air-water two-phase flow; critical velocity; diameter effect; roughness; VOF model; bottom outlet; experiment;

   Sammanfattning : Undesired air entrainment in bottom outlet conduits of dams may cause pressure transients, leading to conduit vibrations, blowback, discharge pulsation and even cavitation, and jeopardize the operational safety. Due to design limitations or construction costs, it is impossible to create an air free environment in a pressurized pipe. LÄS MER

5. 4. 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

7. 5. CFD MODELLING AND EXPERIMENTS ON AERATOR FLOW IN CHUTE SPILLWAYS

   Författare :Penghua Teng; James Yang; Anders Wörman; Anton Schleiss; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spillway Aerator; Cavitation; Air Entrainment; Two-phase Flow; VOF; Mixture Model; Two-Fluid Model; Air Cavity; Cavity Air Pressure; Air Concentration; Shadowgraphic Image Method SIM ; High-speed Particle Image Velocimetry HSPIV ; Bubble Tracking Method BTM ; luftningsramp; kavitation; luftinträngning; tvåfasflöde; VOF; Mixture Model; Two-Fluid Model; luftkavitet; kavitetslufttryck; luftkoncentration; skuggrafisk bildmetod; hastighetsmätning med höghastighetspartikelfotografering; bubbelspårningsmetod; Byggvetenskap; Civil and Architectural Engineering;

   Sammanfattning : A chute spillway is a typical component of large dams for discharging floods. Because of the high water head, the flow velocity in the chute is often in excess of 20 m/s. Consequently, the structure is usually prone to cavitation damages. Flow aeration is evidenced to efficiently eliminate or to mitigate the damages. LÄS MER