Experimental and Numerical Investigations of Sand-Water Slurry Jets in Water

• Author / Creator

  Azimi, Amir Hossein

• Sand-laden jets can be found in many engineering applications, such as, marine bed capping, mining operations, hydro-transport, dredging material disposal, and discharge of industrial and domestic wastewater. Understanding the dynamic interactions of the sand particles and its ambient are important for proper design and optimizing the engineering systems. Mass, momentum and energy of the system can be influenced by interactions of the suspended particles within the jet. As a result, the hydrodynamics of the flow of particle and fluid velocities, turbulence, and shear stresses are affected by particle interaction mechanisms which increase the complexity of the system and mixing phenomenon. The conducted experimental studies and numerical modeling in this thesis are new in terms of the fundamental understanding, flow characteristics and numerical techniques in simulation of sediment laden jets in water. The obtained results of this study can be used in many other environmental problems, such as marine construction, building artificial islands, deep ocean mining and discharge of sewage sludge into water bodies.
  Part of this thesis focused on the numerical investigation of sand and slurry jets. Effects of the controlling parameters of the jets such as, particle size, nozzle diameter, initial velocity and particle concentration were investigated and it was found that in contrast with single-phase water jet, the water-phase spreading of slurry jets is function of nozzle size and particle concentration. Numerical experiments revealed that the water-phase centreline velocity of slurry jets increased with increasing particle concentration. Empirical formulations were introduced to show these strong correlations between densimetric Froude number, particle concentration and the velocity decay of slurry jets.
  Particle-laden jets are commonly observed when particles are released instantaneously into water bodies but less attention has been devoted to study the starting of particle-laden jets and jet front with relatively high particle concentrations. It was found that the jet front terminal velocities, uf∞, of small particles were as large as 5 times of the individual particle settling velocity, u∞.

• Subjects / Keywords

  • Slurry jets
  • Solid-liquid jets
  • Two phase flow
  • Turbulent jets

• Graduation date

  Fall 2012

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3FT4P

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.