A ground structure based topology optimization method for thermofluid problems

In this thesis, a ground structure based thermofluid topology optimization (TO) method is presented which is applicable to problems with creeping flow. Fluid channels with creeping flow are found in a variety of engineering applications, primarily in the field of microfluidics. Current fluid channel TO is typically done with density-based TO and...

Turbulence Decay of a Shear-Thinning Fluid in Pipe Flow: A DNS Study

The human body is the subject of several interesting phenomena and blood flow comes under that category. The main motivator for this thesis is the flow of blood in aneurysms. An aneurysm is a sudden expansion of an artery, with large expansion angles causing an adverse pressure gradient and leading to flow separation. Several studies have shown...

Pulsatile Flows: Experimental Investigation of fully turbulent pulsatile pipe flows

Turbulence is a commonly encountered state of fluid dynamics. Unsteady turbulent flows in pipes are present in many engineering applications and also in biological flows. However, the various processes active in such flows are not well understood. The present work employs stereo-PIV to investigate the effects of a sinusoidal pressure gradient on...

Towards effective emission regulations: A numerical and experimental study on flow measurement uncertainty in stacks

Accurate measurement of emissions (i.e. volume flow rate multiplied by concentration) is vital to the control and reduction of air pollution. We quantify the uncertainty of flow measurements by S-type pitot tubes in narrow exhaust stacks (diameter < 0.5 m) in support of recent European Union (EU) regulations for emissions from medium-size...

Controlled ring vortex injection into a turbulent pipe flow

In this thesis a vortex generator is presented, that can generate controlled ring-vortex injections into a pipe flow. The performance of the generator and the coherence of its structures is tested by applying a dye visualisation method. Furthermore, iso-contour plots of the 3D velocity field, obtained from Stereoscopic Particle Image Velocimetry...

CFD of multiphase pipe flow: A comparison of solvers

Pipelines with multiphase flow of gas, oil, and water are commonly used in the oil and gas industry. In the presence of offshore platforms or vessels, the pipeline ends with a vertical riser. A possible new concept is to use a single large diameter pipeline along the sea floor that ends into multiple smaller diameter risers. This concept might...

Turbulence Modelling of Two Phase Stratified Channel and Pipe Flows

Stratified two phase flow is one of the flow regimes that is of importance in multiphase flow transport through pipelines, such as used for example in the oil and gas industry. Its application also extends to chemical production, energy conversion and food processing. The phenomenon of turbulence further complicates the stratified flow behaviour...

The stability region of the tubing performance relation curve

The tubing performance relation curve is a measure of well performance in gas well engineering. It describes the two-phase flow inside a well and as such is modeled as a two-phase one dimensional pipe flow. Convention claims that production points on the TPR curve to the right of its minimum are stable. There also exist claims about the region...

Verslag van een onderzoek naar de krachten op een éénzijdige klep in een buis t.g.v. een stationaire vloeistofstroming

De drukverdeling rond een rechte klep met gegeven lengthe en gegeven stand, die éénzijdig tegen de wand van een buis bevestigd is, wordt benaderd m.b.v. een berekening volgens de tweedimensionale potentiaaltheorie. De feitelijke berekening is die van de vrije uitstroming van een ideale vloeistof uit een gesloten tweedimensionale buis, zonder...