Controlling the breakup of spiralling jets: results from experiments, nonlinear simulations and linear stability analysis

We experimentally and numerically study the dynamics of a liquid jet issued from a rotating orifice, whose breakup is regulated by a vibrating piezo element. The helical trajectory of the spiralling jet yields fictitious forces varying along the jet whose longitudinal projections stretch and thin the jet, affecting the growth of perturbations....

Continuous and Discrete Algorithms for Modelling the Kessler Syndrome

This thesis contains the development of continuous Kepler orbit- and a discrete numerical integration-based collision detection algorithms in a system of LEO satellites, which in combination with collision algorithm form a simplified space debris evolution model. This model is then used to study the Kessler syndrome. The continuous and discrete...

Polarimetric SAR signals of river ice breakup

Ice jam events can be devastating for the environment, human infrastructure, and local population. During breakup season, it is of great importance to be informed about the river ice cover condition in order to mitigate breakup flood risk. The Athabasca River near FortMcMurray, located in Alberta, is particularly prone to ice jam events and...

Response of DNA molecules to external fields: Electric and hydrodynamic

CFD Study of Piston Cooling Using Oil Jets

For heavy duty diesel engines, piston temperature control is very important in constructing a successful design that meets the demands of increasing power output and stringent emission regulations. Overheating of piston is avoided with engine oil through spray cooling and gallery cooling processes. In this research project, evolution and...

Droplet-Turbulence interactions and quasi-equilibrium dynamics in turbulent emulsions

We perform direct numerical simulations (DNS) of emulsions in homogeneous isotropic turbulence using a pseudopotential lattice-Boltzmann (PP-LB) method. Improving on previous literature by minimizing droplet dissolution and spurious currents, we show that the PP-LB technique is capable of long stable simulations in certain parameter regions....

Thermal fluctuations in capillary thinning of thin liquid films

Thermal fluctuations have been shown to influence the thinning dynamics of planar thin liquid films, bringing predicted rupture times closer to experiments. Most liquid films in nature and industry are, however, non-planar. Thinning of such films not just results from the interplay between stabilizing surface tension forces and destabilizing...

Analysing jet breakup: An experimental study on Rayleigh-Plateau instability and subsequent droplet formation

This report aimed to investigate jet-breakup through nozzles and its dependencies on viscosity, flowrate and nozzle diameter. By measuring the transition point from dripping to jetting as a function of nozzle diameter and viscosity, it was found that increasing nozzle diameters require increasing flowrates to reach jetting mode, while increasing...

Breakup of confined droplets in microfluidics

Segmented-flow microreactors have emerged as an attractive tool for fine chemical synthesis and (bio)chemical analysis, owing to their high heat and mass transfer rate, low axial dispersion, as well as rapid mixing. A key challenge for the use of segmented-flow microreactors in large-scale processing is their low throughput. This can be overcome...

Breakup of polystyrene particles in turbulent Taylor-Couette flow: Vallidation of a DNS model for asphaltene agglomeration

The study of polystyrene particles in Talor-Couette flow for the vallidation of a DNS code for asphaltene agglomeration

Dynamics of droplet breakup in a T-junction

The breakup of droplets due to creeping motion in a confined microchannel geometry is studied using three-dimensional numerical simulations. Analogously to unconfined droplets, there exist two distinct breakup phases: (i) a quasi-steady droplet deformation driven by the externally applied flow; and (ii) a surface-tension-driven three-dimensional...

Man-made islands in Mackenzie River: Evaluation of hydraulic design

Norman Hells is situated on the north bank of the Mackenzie River, 145 km south of the Arctic Circle. The use of a pool-wide water flood system for secondary recovery and the features of the oil-bearing structure require six man-made platforms to provide vertical access to the portion of the oil pool that 1 ies beneath the Mackenzie River (60%)....