Sökning: "Pipe flow"
Visar resultat 1 - 5 av 129 avhandlingar innehållade orden Pipe flow.
1. Experimental study of turbulent flows through pipe bends
Sammanfattning : This thesis deals with turbulent flows in 90 degree curved pipes of circular cross-section. The flow cases investigated experimentally are turbulent flow with and without an additional motion, swirling or pulsating, superposed on the primary flow. LÄS MER
2. Stability of plane Couette flow and pipe Poiseuille flow
Sammanfattning : This thesis concerns the stability of plane Couette flow and pipe Poiseuille flow in three space dimensions. The mathematical model for both flows is the incompressible Navier--Stokes equations. Both analytical and numerical techniques are used. We present new results for the resolvent corresponding to both flows. LÄS MER
3. A Study of Using Pulsed Neutron Activation for Accurate Measurements of Water Flow in Pipes
Sammanfattning : The objectives of this work were 1) to investigate the performance of the pulsed neutron activation (PNA) method for determination of mass flow of water in pipes, and 2) to improve the accuracy such that an error less than 1% become possible with the PNA method. The ultimate purpose is to develop this method into a high-accuracy portable and non-intrusive flow-meter that easily can be used as a calibration tool at a number of field applications, e. LÄS MER
4. Distributed thermal response tests : New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes
Sammanfattning : U-pipe Borehole Heat Exchangers (BHE) are widely used today in ground source heating and cooling systems in spite of their less than optimal performance. This thesis provides a better understanding on the function of U-pipe BHEs and Investigates alternative methods to reduce the temperature difference between the circulating fluid and the borehole wall, including one thermosyphon and three different types of coaxial BHEs. LÄS MER
5. Studies of sound generation and propagation in flow ducts
Sammanfattning : This thesis contains three papers investigating problems of interest for noise control in ducts. The first part of this thesis treats the sound propagation in rectangular ducts with flexible walls. Various experimental techniques are performed to measure the internal sound propagation and radiation to the surrounding. LÄS MER