11 The Orapa Diamond Mine (Republic of Botswana) exposes a bi-lobate kimberlite 12 pipe that erupted during the Late-Cretaceous epoch (∼93 Ma) through Archaean 13 basement and volcano-sedimentary rocks of the Karoo Supergroup. Geological map14 ping of the crater zone of the South Pipe has revealed a 15–25 m thick in-situ 15 kimberlite pyroclastic flow deposit. The pyroclastic deposit fills in t...

Computations of liquid–solid slurries in horizontal pipes are performed to investigate the complex multiphase flow dynamics associated with operating conditions above and below the critical deposition velocity. A high-fidelity large eddy simulation framework is combined with a Lagrangian particle tracking solver to account for polydispersed settling particles in a fully developed turbulent flow...

This thesis develops analytical solutions for estimating the bending moments and axial loads in a buried pipeline due to ground movements caused by tunnel construction in soft ground. The solutions combine closed-form, analytical solutions for tunnel-induced, free-field ground deformations in a plane orthogonal to the heading (Pinto and Whittle; 2001) with Winkler models for pipe-soil interacti...

An inverse analysis model was developed which provides a mathematical framework for interpretation, in terms of the condition of a buried pipeline, of survey data in the presence of random noise. A boundary-element forward model was coupled with a weighted nonlinear regression algorithm to obtain pipe surface properties from two types of survey data: soil-surface potentials and local values of ...

We present the dynamic velocity profiles of a Newtonian fluid (glycerol) and a viscoelastic Maxwell fluid (CPyCl-NaSal in water) driven by an oscillating pressure gradient in a vertical cylindrical pipe. The frequency range explored has been chosen to include the first three resonance peaks of the dynamic permeability of the viscoelastic-fluid--pipe system. Three different optical measurement t...

Vertical pneumatic transport in a lab-scale vertical lifter has been studied using Laser Doppler Anemometry (LDA). The experimental system consists of a lower fluidized silo, an upper receiving tank and a connecting vertical transport pipe made of clear glass. The experimental study has been performed in order to get detailed information of the complex gas-particle flow behavior in a dilute ver...

Effective cuttings transport means a better hole cleaning in drilling operations, which can increase the rate of penetration (ROP), and avoids pipe sticking, higher drag and torque problems. This paper aimed to analyze cuttings transport efficiency affected by different blade shapes of stabilizers, which is often overlooked in drilling. For this purpose, Eulerian multiphase flow model was used ...

We review the current understanding on universal behaviors in granular flows through a vertical pipe and traffic flows. We carry out weakly nonlinear analysis of a model for traffic flows based on the technique of soliton perturbations, and determine the selected propagating velocity, the amplitude, the width of interfaces connecting between jam phase and non-jam phase. From the direct simulati...

Our goal is to model and analyze a stationary fluid flow through the junction of two pipes in the gravity field. Inside ’vertical’ pipe there is a heavy piston which can freely move along the pipe. We are interested in the equilibrium position of the piston in dependence on geometry of junction. Fluid is modeled with the Navier-Stokes equations and the piston is modeled as a rigid body. We form...