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Visar resultat 1 - 5 av 44 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Numerical Prediction of Propeller Induced Hull Pressure Pulses

   Författare :Muye Ge; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cavitation; Pressure pulses; RANS; OpenFOAM; Star-CCM ;

   Sammanfattning : Ship propeller induced pressure pulses is one of the major sources of both onboard noise and vibration as well as underwater radiated noise. The need for accurate pressure pulse prediction is increasing due to rising concerns of environmental impacts and comfort and welfare of passengers and crews. LÄS MER

3. 2. Numerical prediction of propeller induced hull pressure pulses and noise

   Författare :Muye Ge; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; RANS; Transition; IDDES; Cavitation; Pressure pulses; Sheet cavitation inception; Ship noise; k − ω SST; FWH acoustic analogy; Hydroacoustics;

   Sammanfattning : An operating marine propeller is one of the major sources inducing hull pressure pulses, onboard noise and vibration as well as underwater radiated noise. There are rising concerns of environmental impacts and comfort and welfare of passengers and crews due to these negative effects. LÄS MER

4. 3. Extracting Cardiac Information From the Pressure Sensors of a Dialysis Machine

   Författare :Mattias Holmer; Avdelningen för Biomedicinsk teknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hemodialysis; extracorporeal pressure signals; cardiac pressure signal; heart rate; ventricular premature beats; venous needle dislodgement;

   Sammanfattning : This doctoral thesis in biomedical engineering deals with cardiac monitoring using the built-in extracorporeal blood pressure sensors of a hemodialysis machine. Patients treated with hemodialysis often suffer from cardiovascular disease. LÄS MER

5. 4. Modelling of the pressure distributions in twin-wire blade formers

   Författare :Claes Holmqvist; KTH; []
   Nyckelord :fluid mechanics; blade forming; pressure distribution; suction; interaction; permeable fabric; modules;

   Sammanfattning : During papermaking, the internal structure of the fibrenetwork constituting the paper is to a dominating extentdetermined in the forming zone of the paper machine. Thisthesis is aimed at studying the pressure distribution in bladeforming sections, which is commonly considered to be a keyquantity of the process. LÄS MER

7. 5. Influence of Acoustic Interaction between Cavities That Generate Cavitation Noise

   Författare :Jan Hallander; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; numerical simulation; collapse of vapour cavities; experimental studies; pressure pulses; cavitation noise; hydrodynamics; cavitation; bubbles; cavitating flows;

   Sammanfattning : The thesis concerns high frequency cavitation noise generated by marine propellers, for example. The collapse of a cavity is forced by the surrounding pressure which comprises the pressure in the undisturbed flow, the pressure disturbance associated with the local non-cavitating flow and, finally, the pressure disturbance from the presence and motion of neighbouring cavities. LÄS MER