Iranian Water Research Journal

Iranian Water Research Journal

Hydraulic investigation of two-phase flow using Doppler velocity meter

Document Type : Original Article

Authors
Mohammadreza zayeri
mehdi ghomeshi
Department of Water Structures, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran
10.22034/IWRJ.2024.14686.2584
Abstract
As a multiphase flow, the Density current is associated with a significant amount of suspended sediments from the river and the basin, and due to its speed and concentration, it also erodes and carries with it a part of the sediments deposited in the previous periods. This flow takes straight or winding paths in the trough of the river. Therefore, in this research, an experimental study of the effect of the relative radius to the width of the channel with ratios of 2, 4 and 6 on the profile of velocity and concentration was carried out using a Doppler velocimeter. By examining the effect of increasing the radius of curvature on the profile of the velocity of concentrated flow in the vertical direction at the end of the arc, it was observed that for a flow rate of 2.5 liters per second and an upstream concentration of 12.5 gr/liter, at a constant concentration and flow rate with a threefold increase in the radius of curvature, The speed in the central axis of the channel increases by 40% due to the reduction of the effect of centrifugal force. Also, the results show that by doubling the turbidity by 2.5%, the velocity profile of the thick flow at the end of the arch increases by 37%. The bed, the position of the maximum flow velocity, is moved towards the bed as the concentration increases.
Keywords
Dense flow
Doppler velocity meter
Relative curvature radius
Velocity profile
Subjects
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  • Receive Date 06 February 2024
  • Accept Date 17 December 2025
  • Publish Date 21 June 2024