Investigation of Non-Newtonian Fluid Effects during Transient Flows in a Pipeline

Abstract

Transient flows associated with the water hammer phenomenon are commonly encountered in both natural and engineering systems, such as hydraulic systems, oil transportation systems, and human arterial network. Sudden changes in pressurized pipe flow conditions caused by valve closure, pump operation, etc. are routine events. The excitations arising from these transient events can cause significant pressures leading to devastating forces [1].The flow of non-Newtonian fluids and slurries in pipes occurs in a wide range of practical applications in the processing industries and many natural systems. If the fluid has a significant yield stress, or if its effective viscosity is high, industrially relevant flow rates may occur in the laminar flow regime.The fluids under consideration in this study are shear-thinning non-Newtonian, whose rheology is described by a generalized Newtonian fluid (GNF) model, i.e. the dependency of isotropic viscosity on flow properties [2] and [3]. In the specific fluids of the present work, the viscosity can be described using either the power law or Cross models. The capability of these models has been investigated by several researchers, including such as Pinho and Whitelaw Herein, unsteady pipe flow of a non-Newtonian fluid is studied. This work may be seen as a new extension to the classic water hammer model in which transients of a Newtonian fluid contained in a straight elastic pipe supported at the valve and along the pipeline with sufficient longitudinal anchors to suppress fluid-structure interaction effects is investigated. Having done this fluid hammer simulation for the power law and Cross models, several alternate works (in terms of studying the other effects [15]) on the transients of these fluids can be offered for future research. They include viscosity Investigation of Non-Newtonian Fluid Effects during Transient Flows in a Pipeline

Numerical modeling of transient non Newtonian thinning fluid flow

“…Where µ0 is the consistency coefficient and n the index behaviour of the fluid and, consequently: )+ , (7) Where 𝞺 is the density of the fluid. The average of the two equations above across aright section of pipe lead to the system below of hyperbolic nature which is, numerically, can be obtained by the method of characteristics [5][6][7]:…”

Cramer-Rao Lower Bound for Performance Analysis of Leak Detection

“…However, for the time-domain water-hammer solution where several parameters may be incorporated in the model, an analytical solution for the CRLB cannot be derived, and a numerical approach is needed. Computational approaches allow for the application of a versatile transient solver that includes advanced models of viscoelasticity, turbulence, fluid-structure interaction, and non-Newtonian fluids, among others, with various types of boundary conditions (Covas et al 2005;Ahmadi and Keramat 2010;Keramat et al , 2013Meniconi et al 2014;Majd et al 2016;Meniconi et al 2017;Ferreira et al 2018). In this view, any arbitrary valve type and consequently valve maneuver with any nonlinear closure pattern or pipe system equipment such as pumps or pressure suppression devices can be adopted in such numerical formulation.…”

Drag Reduction Characteristics of Bionic Structure Composed of Grooves and Mucous Membrane Acting on Turbulent Boundary Layer

“…Fish mucus can be imitated by using a chemically synthesized viscoelastic fluid, which is injected into the flow field as a DRA to form a mixed solution. This solution is primarily used in pipeline transportation to significantly reduce fluid drag (Majd et al 2016;Vilalta et al 2016;Graham 2014). The drag reduction method of secreting mucus on the surface of an underwater vehicle to form a mucous membrane was first proposed by Zhang et al (Zhang et al 2020a) After Toms theory (Toms 1948) was proposed, viscoelastic fluid drag reduction became a significant area of research.…”