Search published articles
Showing 2 results for Sadeghi Dodaran
Mostafa Nabipour, Ali Akbar Salehi Neyshabouri, Reza Sadeghi Dodaran, Amir Reza Zarrati, Hossein Mohajeri, Mohammad Zabetian,
Volume 18, Issue 1 (3-2018)
Abstract
One of the practical and useful techniques for the flow field measurement in open channels is Acoustic Doppler Velocimeter (ADV). Presence of ADV probe and its holding system against flow disturb natural flow pattern which can change turbulent flow structure. Thus, the error of the Acoustic Doppler Velocimeter is consist of its intrinsic error and the presence of ADV against flow. To have better understating about this effect, in this paper, flow field in an open-channel is measured using Particle Image Velocimetry (PIV) technique and side-looking ADV probe. The results show that sreamwise velocity obtained from both methods are in good agreement and on average, there is 5 percent difference, while vertical and lateral components of velocity are considerably different. Also, comparison of sreamwise and lateral turbulence intensities and the Reynolds shear stress shows lower differences for measured points near the water surface and the differences increase approaching to the bed.
R. Sadeghi Dodaran, S.a.k. Salehi Neyshaburi, M. Nabipoor, S.h. Mohajeri, A.r. Zarrati,
Volume 19, Issue 12 (December 2019)
Abstract
Acoustic doppler velocimetry (ADV) is a common measurement technique for flow field in open-channel flows. Since ADV is an intrusive measurement method, the presence of ADV probe may causes changes in flow structure and may intensify the turbulence in sampling volume which can affect the experimental results and analysis. To explore these effects, in this study, particle image velocimetry (PIV) was employed to measure the flow field with and without the presence of a side looking ADV probe in a compound channel. The results of this research showed that the intrusion of ADV in the flow field increases the streamwise velocity in the ADV measurement volume by 1.7%. The more enhanced effect is also notified in the secondary currents so that in the present test conditions, the presence of the side looking ADV causes a decrease in lateral velocity by 4.5 times and causes an increase in vertical velocity by 2.7 times. Investigation of the turbulent intensities showed that the presence of the side looking ADV causes an increment in streamwise turbulent intensity, while does not significantly affect the lateral and vertical components. Furthermore, examining vertical Reynolds shear stress measurement data with or without the presence of ADV showed that the measured values differ in the two states and the presence of ADV decreases 30% of Reynolds shear stress in place of the control volume.
