Sökning: "Critical velocity"
Visar resultat 1 - 5 av 132 avhandlingar innehållade orden Critical velocity.
1. Modelling air―water flows in bottom outlets of dams
Sammanfattning : If air is entrained in a bottom outlet of a dam in an uncontrolled way, the resulting air pockets may cause problems such as blowback, blowout and loss of discharge capacity. In order to provide guidance for bottom outlet design and operation, this study examines how governing parameters affect air entrainment, air-pocket transport and de-aeration and the surrounding flow structure in pipe flows. LÄS MER
2. Air-pocket transport in conjunction with bottom-outlet conduits for dams
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
3. Discrete Scale-Space Theory and the Scale-Space Primal Sketch
Sammanfattning : This thesis, within the subfield of computer science known as computer vision, deals with the use of scale-space analysis in early low-level processing of visual information. The main contributions comprise the following five subjects:The formulation of a scale-space theory for discrete signals. LÄS MER
4. Vibrations from Railway Traffic : Computational Modeling and Analysis
Sammanfattning : The population is growing, and an increasing proportion of the population lives in urban areas. As a consequence, human exposure to noise and vibrations is increasing; two major sources being railway and road traffic. Larger and denser cities lead to a higher amount of traffic close to where people work and live. LÄS MER
5. Estimating the Air-Water Gas Transfer Velocity during Low Wind Conditions
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