This paper clearly explains the use of drift flux models based on Eulerian continuum equations in predicting erosion wear rate in a transmission pipeline. In this case, a pipeline with a diameter of 0.5m was investigated. It was found that there was a large sand particle concentration on the welded parts of the pipe which has affected the internal geometry of the pipe. From physical examination...

As a part of component integrity test program at Bhabha Atomic Research Centre, fatigue tests on full scale pipe and pipe welds were conducted in addition to CT and TPB specimens. In this paper the outcome of this program is discussed. Specimen testing was conducted to determine the basic cyclic stress strain curve, LCF and FCGR properties. FCGR tests were conducted on CT and TPB specimens to u...

Results of a numerical study on the finite amplitude global perturbations inducing transition to turbulence in pipe flow are reported. The aim of this analysis is to characterise the basin of attraction of the basic Hagen-Poiseuille flow (which is believed to be lineary stable for all Reynolds numbers Re) by means of the minimal amplitude of an initial global perturbation triggering transition....

The failure of normal-mode linear stability analysis to predict a transition Reynolds number (Retr) in pipe flow and subcritical transition in plane Poiseuille flow (PPF) has led to the search of other scenarios to explain transition to turbulence in both flows. In this work, various results associated with linear and nonlinear mechanisms of both flows are presented. The results that combine an...

There have been many investigations of the stability of Hagen-Poiseuille flow in the 125 years since Osborne Reynolds' famous experiments on the transition to turbulence in a pipe, and yet the pipe problem remains the focus of attention of much research. Here, we discuss recent results from experimental and numerical investigations obtained in this new century. Progress has been made on three f...

In many urban areas of the developing world, piped water is supplied only intermittently, as valves direct water to different parts of the water distribution system at different times. The flow is transient, and may transition between free-surface and pressurized, resulting in complex dynamical features with important consequences for water suppliers and users. Here, we develop a computational ...

A solution layer crystallization process in a concentric annulus is presented that removes the need for filtration. A dynamic model for layer crystallization with and without a recirculation loop is developed in the form of coupled partial differential equations describing the effects of mass transfer, heat transfer, and crystallization kinetics. The model predicts the variation of the temperat...

Detonations and deflagration-to-detonation transition (DDT) are experimentally studied in horizontal pipes which are partially filled with water. The gas layer above the water is stoichiometric hydrogen–oxygen at 1 bar. The detonation wave produces oblique shock waves in the water, which focus at the bottom of the pipe due to the curvature of the walls. This results in peak pressures at the bot...

The analyzed electrohydraulic servo valve is jet pipe type, is one of the mechatronics component used for precision flow control application. The jet pipe servo valves have one movable nozzle and two collector ports, from where fluid is ducted to the main valve spool. The servovalve analyzed here is basically used in fuel control application in Variable Geometry Actuation System (VGAS) of a gas...