Fluid flow measurements by means of vibration monitoring

Abstract

The achievement of accurate fluid flow measurements is fundamental whenever the control and the monitoring of certain physical quantities governing an industrial process are required. In that case, non-intrusive devices are preferable, but these are often more sophisticated and expensive than those which are more common (such as nozzles, diaphrams, Coriolis flowmeters and so on). In this paper, a novel, non-intrusive, simple and inexpensive methodology is presented to measure the fluid flow rate (in a turbulent regime) whose physical principle is based on the acquisition of transversal vibrational signals induced by the fluid itself onto the pipe walls it is flowing through. Such a principle of operation would permit the use of micro-accelerometers capable of acquiring and transmitting the signals, even by means of wireless technology, to a control room for the monitoring of the process under control. A possible application (whose feasibility will be investigated by the authors in a further study) of this introduced technology is related to the employment of a net of micro-accelerometers to be installed on pipeline networks of aqueducts. This apparatus could lead to the faster and easier detection and location of possible leaks of fluid affecting the pipeline network with more affordable costs. The authors, who have previously proven the linear dependency of the acceleration harmonics amplitude on the flow rate, here discuss an experimental analysis of this functional relation with the variation in the physical properties of the pipe in terms of its diameter and constituent material, to find the eventual limits to the practical application of the measurement methodology.

Measuring water flow rate for a fire hose using wired accelerometers for smart fire fighting

“…The mean of all 50 data collection increments for Test 3 are shown in Fig 26 with standard deviation bars. The dominant frequency decreased consistently with increasing flow rate as expected [13,15,18]. A dominant frequency value is not shown for 0 LPM because the signal noise instead of the hose flow dominated the signal.…”

“…25). When water is flowing through a rigid pipe, the dominant frequency typically does decrease with increasing flow rate [13,15,18]. Thus, a similar trend was expected for flexible hose.…”

“…11, have been reported [21]. Based on previous research, the natural frequency of a rigid pipe system generally decreases with increasing water flow rate through the pipe [13,15,18]. Fig.…”

“…Dinardo et al [17] and Campagna et al [18] used a laser Doppler vibrometer (LDV) to measure pipe vibrations due to internal fluid flow. Dinardo et al showed a linear relationship between the first harmonic amplitude of the transverse acceleration and the flow rate inside a pipe.…”

Measuring water flow rate for a fire hose using a wireless sensor network for smart fire fighting

“…Vibrations from fluid or gas flow can occur in any relatively rigid pipe such as water, oil, and gas utility or industrial pipes. Wired sensors, including accelerometers, have been attached securely to the outside surface of rigid pipes to measure fluid or gas induced pipe vibrations to determine flow rate within the pipe in research settings as well as in the utility pipeline industry [3][4][5][6][7][8][9][10][11][12][13][14][15][16].…”