In this thesis, unsteady friction in transient pipe flow is given a closer look. The common quasi-steady friction model and two one-dimensional convolution-based models, developed by Zarzycki and Vardy & Brown, are considered. A quasi-two-dimensional approach to the water hammer problem is also derived, where the pipe friction is related to the near-wall behavior of the velocity profile. The mo...

In this thesis capillary dominated two–phase flow is studied by means of numerical simulations and experiments. The theoretical basis for the simulations consists of a phase field model, which is derived from the system’s thermodynamics, and coupled with the Navier Stokes equations. Two types of interfacial flow are investigated, droplet dynamics in a bifurcating channel and spontaneous capilla...

The Manning friction coefficient as a one-dimensional (1D) openchannel flow parameter is determined from a series of two-dimensional (2D) simulations of the flow on steep slopes using a computational hydraulic solver derived from a minimal intervention strategy (MIS2D). Computations are also conducted for the oblique dam-break waves to evaluate the performance of MIS2D. The results are compared...

the objective of this study was to develop a numerical model for the prediction of temperature distribution, effective plastic strain distribution, and especially material flow in friction stir welding of copper plates. the deform-3d software was used by incorporating a lagrangian incremental formulation. threedimensional results of the material flow pattern which were extracted using the point...

The Hasimoto planar vortex filament is one of the rare exact solutions to the classical local induction approximation (LIA). This solution persists in the absence of friction or other disturbances, and it maintains its form over time. As such, the dynamics of such a filament have not been extended to more complicated physical situations. We consider the planar vortex filament under the quantum ...