Fundamental Characteristics of Drag-reducing Micelle Solution Turbulent Flow Across Abrupt Expansion Pipe
نویسندگان
چکیده
منابع مشابه
Measurement of temperature profiles in turbulent pipe flow of polymer and surfactant drag-reducing solutions
A device was built to measure temperature profiles of turbulent pipe flows of various drag-reducing fluids. It is easy to use and reliable. We measured temperature profiles over a range of conditions leading to accurate measurements down to y+ 10, for tests carried over Reynolds numbers Re between 10 000 and 90 000. The effects of high heat fluxes and buoyancy, in particular, were quantified to...
متن کاملManipulating Flow Structures in Turbulent Pipe Flow
Two different tools, the non-empirical resolvent analysis and the data-based dynamic mode decomposition, are employed to assess the changes induced by transpiration in the dynamics of a turbulent pipe flow. The focus is on very large-scale motions. Both analyses permit the observation of streamwise waviness in the large flow structures and how the transpiration can inhibit fluctuation in locali...
متن کاملA Mechanism of Polymer Induced Drag Reduction in Turbulent Pipe Flow
Polymer induced drag reduction in turbulent pipe flow was investigated using a non-intrusive laser based diagnostic technique, namely Particle Image Velocimetry (PIV). The drag reduction was measured in a pressure-driven flow facility, in a horizontal pipe of inner diameter 25.3 mm at Reynolds numbers ranging from 35 000 to 210 000. Three highmolecular-weight polymers (polyethylene oxide 2×10 6...
متن کاملExperiments in Turbulent Pipe Flow with Polymer Additives at Maximum Drag Reduction
In this paper we report on (two-component) LDV experiments in a fully developed turbulent pipe flow with a drag-reducing polymer (partially hydrolyzed polyacrylamide) dissolved in water. The Reynolds number based on the mean velocity, the pipe diameter and the local viscosity at the wall is approximately 10000. We have used polymer solutions with three different concentrations which have been c...
متن کاملOptimally amplified large-scale streaks and drag reduction in turbulent pipe flow.
The optimal amplifications of small coherent perturbations within turbulent pipe flow are computed for Reynolds numbers up to one million. Three standard frameworks are considered: the optimal growth of an initial condition, the response to harmonic forcing and the Karhunen-Loève (proper orthogonal decomposition) analysis of the response to stochastic forcing. Similar to analyses of the turbule...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Mechanical Engineering
سال: 2019
ISSN: 0577-6686
DOI: 10.3901/jme.2019.04.226