Iranian Journal of Mechanical Engineering Transactions of ISME

Iranian Journal of Mechanical Engineering Transactions of ISME

Experimental Investigation of Frequency Spectrum of Vortex Shedding from a Dual Bluff Body Placed in Series

Authors
Ehsan Ardekani 1
Foad Farhani 2
Mohammad Ali Ardekani 3
1 PhD Student, Department of Mechanical Engineering, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran
2 Associate Professor, Department of Mechanical Engineering, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran
3 Professor, Department of Mechanical Engineering, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran
10.30506/ijmep.2025.2047076.2001
Abstract
Using a dual bluff model has been considered an approach to enhancing the vortex flowmeter's accuracy. In this experimental research work, the vortex shedding from a dual cylindrical bluff model of semicircular cross-section, placed in series, at different  ratios, where  is the diameter and  is the distance between the two semicircular cylinders in series is measured and investigated using a wind tunnel and hot-wire anemometer.
Results show that the Strouhal number decreases with an increase in , also show that the standard deviation of the repeatability of the Strouhal number reading and using the Gauss Normal Distribution for  and , a dual cylindrical bluff model of semicircular cross-section, placed in series, is suitable for vortex flowmeter application. In this case, at a 95% confidence level, the measurement accuracy is less than 1.8%.
Keywords
Dual bluff body
Frequency spectrum
Strouhal number
Vortex flowmeter
Vortex shedding

Subjects

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  • Receive Date 01 December 2024
  • Revise Date 05 January 2025
  • Accept Date 02 March 2025