Vortex Flowmeter Research Articles

Measurements of CO2 Absorption and Heat Consumption in Laboratory Rig

Abstract An absorption and desorption rig has been in operation at Telemark University College since 2010. The purpose of the rig is to perform measurements of CO2 removal efficiency and heat consumption at different process conditions like temperatures, flows and CO2 concentrations in the gas and the liquid. 30 wt-% monoethanolamine (MEA) in water has been the most used solvent. In earlier work, the heat consumption has been indirectly measured by the electricity consumption for steam production. In this work new results from 2012 and 2013 are presented where the steam consumption has been measured directly by a vortex flow meter.

鉛直円管内気液二相流中における超音波式渦流量計の計測可能範囲と計測部の可視化

鉛直円管内気液二相流中における超音波式渦流量計の計測可能範囲と計測部の可視化

Performance evaluation of piezoelectric and differential pressure sensor for vortex flowmeters

Piezoelectric and transient differential pressure sensors are two among the most widely employed sensors for vortex flowmeter application. The present study evaluates the performance of these two techniques under fully developed and disturbed flow conditions. Firstly, the location of the transient differential pressure sensor is optimized to obtain high amplitude signals and good linearity in Strouhal number. Empirical mode decomposition method in combination with autocorrelation decay is successfully employed at high Reynolds numbers to identify the vortex shedding frequency in presence of hydrodynamic noise. The performance of the differential pressure sensor deteriorates significantly under disturbed flow conditions at low Reynolds number due to the presence of low frequency components. This deterioration in the signal quality limits the lower operating range of the flowmeter with differential pressure sensor. The output signals of the piezoelectric sensor and differential pressure sensor under no flow condition are compared to obtain the background noise due to piping vibrations and electrical interferences. These results will help a designer to suggest robust signal processing algorithms for vortex frequency detection.

Computationally lean algorithm of novel optimal FIR adaptive filter for vortex signal extraction

In a vortex flowmeter vortices are generated by a bluff body, inserted in the path of flow, which has a piezoelectric sensor embedded in it. This piezosensor develops a signal having a fundamental frequency that is proportional to flow. The flow measurement relies completely on extraction of true vortex signal and estimation of the correct frequency. A novel adaptive FIR filter has been designed and implemented using low power computational resource (8.25mW), which gives better results than an existing contemporary system when tested on an industrial flow rig. Further more a comparative study of autocorrelation, EMD Scales filter and proposed algorithm is carried on the good and bad vortex signals. From this comparative study it is seen that proposed algorithm is effective for bad vortex signals and low flowrates where vortex signals are weak.

Разработка виртуального испытательного стенда для численного моделирования гидродинамических течений в бесфланцевых вихревых расходомерах с использованием высокопроизводительных вычислений

This paper describes results of development of virtual test bench and using of CFD models for inner part of flangeless vortex flowmeter for virtual test bench running on Tornado SUSU supercomputer. The structure of virtual test bench is presented. The results of numerical simulation of flow (air and water) in inner part of flangeless vortex flowmeter are introduced.

Response of a dual triangulate bluff body vortex flowmeter to oscillatory flow

In this paper, on an experimental facility, the measurement characteristics of a diameter 50mm dual triangulate bluff body vortex flowmeter in steady flow and oscillatory flow were investigated. Then, the Hilbert Huang Transformation (HHT) method was used to assess the anti-interference performances and the vortex street stability in oscillatory flow for the dual triangulate bluff body vortex flowmeter and a single bluff body vortex flowmeter. Offline simulation was carried out on the anti-interference performances of the dual triangulate bluff body vortex flowmeter signal noise in oscillatory flow by the method of the EMD-scales filter. The major findings are: (a) in most case, the EMD-scales filter may be as good at de-noising effect for the dual bluff body vortex flowmeter in oscillatory flow than that for the single bluff body vortex flowmeter in oscillatory flow. The vortex street stability in oscillatory flow for the dual bluff body is similar to that for the single bluff body. (b) In some special case, the EMD-scales filter is unable to play a better de-nosing role for the dual bluff body vortex flowmeter in oscillatory flow. The invalid condition of the EMD-scales filter for the dual bluff body vortex flowmeter in oscillatory flow is different to that of the single bluff body vortex flowmeter and it was advanced in this paper. (C) The vortex street stability for the dual bluff body vortex flowmeter is better than that for the single bluff body vortex flowmeter.

The Hydraulic Stability of Heating Network with Remote Measurement and Control System

In order to eliminate hydraulic imbalance phenomenon of the heating network, this article briefly introduces the operation principle of the system. The remote control system uses computer information and communication technology to monitor the network flow, through the pressure curve to estimate the hydraulic condition. According to the analysis of pipe resistance properties and the hydraulic balance calculation, the system will change the valve opening intelligently, to make the heating network running in a hydraulic balance condition. The vortex flow meter and flow control valve can be used to adjust the water flow of primary and secondary network, such measure will ensure the hydraulic stability of heating system, save the thermal energy consumption.

Design of Conversion Circuit for Intellect Vortex Flow-Meter

The design principles of conversion circuit for intellect vortex flow-meter with MSP430 microcontroller used as the core was described in detail. The implementation plan of system development was confirmed based on the analyzing of the key technology of vortex flow-meter, which collected and processed the pulse signal from the pre-amplified circuit and sent to the module of D/A conversion converted into standard 4 ~ 40 mA output. The key of the design of hardware circuit and implementation of software was stated. The result tested and approved by the site shows that the technology index has met the design requirement with the character of reliability, which solves the problem of the large wastage of power and low stability. Its performance can be comparable with that of the same import products and its cost is much lower. It has a broad market prospect.

Influence of bluff body shape on wall pressure distribution in vortex flowmeter

To investigate the influence of bluff body shape on wall pressure distribution in a vortex flowmeter, experiments were conducted on a specially designed test section in a closed water rig at Reynolds numbers of 6.2×104-9.3×104. The cross sections of the bluff bodies were semicircular, square, and triangular shaped, and there were totally 21 pressure tappings along the conduit to acquire the wall pressures. It is found that the variation trends of wall pressures are basically identical regardless of the bluff body shapes. The wall pressures begin to diverge from 0.3D (D is the inner diameter of the vortex flowmeter) in front of the bluff body due to the diversity in shape, and all reach the minimum values at 0.3D behind the bluff body. A discrepancy between the triangular or square cylinder and the semicircular cylinder in wall pressure change is observed at 0–0.1D behind the bluff body. It is also found that the wall pressures and irrecoverable pressure loss coefficients increase with flow rates, and the triangular cylinder causes the smallest irrecoverable pressure loss at a fixed flow rate.

F082003 各種蒸気流量計による湿り蒸気流量計測(【F08200】湿り蒸気流量計測,動力エネルギーシステム部門企画,先端技術フォーラム)

It is well known that the wetness of steam flow sometimes causes measurement errors of the steam flow meter. However, it is difficult to clarify a particular error quantitatively in actual plants and factories, and thus far, there has been no established method for estimating the error caused by the wetness of steam flow. Therefore, wet steam flow rate measurement experiments were conducted to clarify the measurement error caused by the wetness of steam flow in a plant and a factory. We have conducted 3 types of the steam flow meter, orifice flow meter, vortex flow meter and ultrasonic flow meter. In this paper, we introduce the correlation between the measurement error and the flow condition and correction methods.

Influence of the Wetness on Flow Rate Measurement of Wet Steam Using a Vortex Flow Meter

Mainly steam is utilized as a means for thermal energy supply in industrial fields. It is important to be aware of the steam flow rate in the view point of energy management. However, steam becomes wet in many cases in the process to be sent through steam pipes to machinery using steam. It is well known that the wetness of steam sometimes causes measurement errors of the steam flow rate, and there has scarcely been the established method for estimating the error caused by the wetness of steam flow. Accordingly, we conducted the experiments of wet steam flow rate measurement to clarify the measurement error caused by the wetness of steam. This paper reports the measurement using a vortex flow meter, following our previous paper using an orifice flow meter(1). The experiments were conducted with the conditions in changing the flow rate, pressure and wetness. As a result, the correlation between the measurement error and the flow condition was clarified.

超音波渦流量計計測における気液二相流中の超音波反射特性と耐気泡性向上策の提案

超音波渦流量計計測における気液二相流中の超音波反射特性と耐気泡性向上策の提案

ИЗМЕРЕНИЕ РАСХОДА ВОЛОКНИСТЫХ СУСПЕНЗИЙ В ЦЕЛЛЮЛОЗНО-БУМАЖНОМ ПРОИЗВОДСТВЕ

In this paper the equipment to measure the flow fiber suspension. A method of testing submersible vortex flowmeters takes into account both the hydrodynamics in a pipeline running meter and properties of the fiber suspension (concentration, degree of grinding, temperature). The mathematical relationships explaining test equipment. Presents the results of research submersible vortex flowmeter for fiber suspension with different concentrations, the degree of grinding and temperature.

Study of the Application of Hilbert-Huang Transform (HHT) based Filtering For A Dual Triangulate Bluff Body Vortex Flowmeter In Oscillatory Flow

Study of the Application of Hilbert-Huang Transform (HHT) based Filtering For A Dual Triangulate Bluff Body Vortex Flowmeter In Oscillatory Flow

Analysis of Pressure Field for Flow Past a Circular Cylinder with a Slit

The signal strength, linearity, stability and measurement range of vortex flowmeter are primarily decided by the shape and geometrical parameters of bluff body. A circular cylinder with a slit was found to produce better vortex signal properties by experiments. Based on previous research, pressure distributions of flow past a circular cylinder are studied by numerical simulation. It is found that the intensity of pressure fluctuation caused by vortex shedding of the circular cylinder with a slit is stronger than that of circular cylinder and 0.2d downstream from the center line of slit at one side of cylinder is found to be an optimal position to detect the vortex signal, where d denotes the diameter of the cylinder. Finally the evolution process of vortex shedding is analyzed to explain why the intensity of pressure varies at different positions.

Frequency detection in vortex flowmeter for low Reynolds number using piezoelectric sensor and installation effects

Piezoelectric sensors are one of the most widely used sensors for vortex flowmeter application due to their low cost. Various researchers have employed piezoelectric sensor for this application. However, the location of the sensor and the performance of vortex flowmeter under disturbed conditions are seldom reported. In the present study, experimental investigations are conducted with water as the working medium in a circular pipe of diameter 52.5mm. The optimum position of the piezoelectric sensor behind the trapezoidal bluff body is found out be 0.85 times the width of the bluff body. A new algorithm based on empirical mode decomposition and autocorrelation decay rate is suggested to identify the vortex shedding frequency under low Reynolds numbers flow condition. The performance of the flowmeter is also evaluated under different disturbed flow conditions to quantify the sensitivity of the flowmeter. The disturbances studied are single 90° bend, gate valve, globe valve, and two 90° out of plane bends. The overall uncertainty in the Strouhal number is within ±1.71%.

Hilbert–Huang transform (HHT) based analysis of signal characteristics of vortex flowmeter in oscillatory flow

In this paper, firstly, on an experimental facility, we investigated the measurement characteristics of a diameter 50 mm vortex flowmeter in steady flow and oscillatory flow. Then, the Hilbert Huang Transformation (HHT) method was used to reduce vortex flowmeter signal noise in oscillatory flow. Offline simulation was carried out on the de-noising of the vortex flowmeter in oscillatory flow by the method of the EMD-scales filter. The de-noising effect was assessed by signal-to-noise ratio (SNR) and relative error of the main frequency between the noisy test signal and reconstructed signal. The major findings are: (a) In a wide range of volumetric flow rate (Q) and the imposed disturbing frequency (f), the EMD-scales filter performs effectively and excellent filtering capability for vortex flowmeter in oscillatory flow. (b) In a specific range of volumetric flow rate (Q) and the imposed disturbing frequency (f), the EMD-scales filter performs ineffectively for vortex flowmeter in oscillatory flow. (c) The invalid condition of the EMD-scales filter for vortex flowmeter in oscillatory flow was advanced in this paper.

Research on Influencing Factors on Errors of Vehicle Fuel Consumption Measured by Carbon Balance Method Based on VMAS

AbstractVehicle fuel consumption measurement using carbon balance method based on VMAS was introduced. The influencing factors of fuel consumption measuring result, including gas concentration measurement, flux measurement, quality of fuel, equipment synchrony and vehicle condition, were analyzed according to the measure theory and structure of measuring system. Analysis of the errors caused by these influencing factors was performed based on the field experimental data obtained under steady test condition. The experiment shows that (1) precision of carbon dioxide sensor and oxygen sensor need to be improved; (2) ultrasonic vortex flow meter cannot satisfy the requirement of the fuel consumption measuring system; (3) equipment synchrony of measuring system has little influence on measuring result under steady condition. The problems of the measuring system which need to be solved were pointed out for improving the fuel consumption measuring precision.

The Vibration Analysis of a Novel Vortex Flowmeter Based on Fiber Bragg Grating

A novel fiber Bragg grating vortex flowmeter was designed in this work, where the Bragg grating was enfolded in a cylinder eddy generator. Bragg grating subject to force and the corresponding strain were analyzed. Subsequently, the relationships between grating’s axial strain and flow were developed. In order to improve the flowmeter's resolution, the system was simplified by a mass-spring-damper model, which was used to analyze resonance and choose acrylic glass as cylinder's material. In terms of the resolution of FBG sensor demodulation device and factors of vortex's formation, the measuring range of flowmeter is 1200L/h~5000L/h. The resolution is less than 40L/h with flow exceeding 2000L/h. The damping ratio is not sensitive to the flow when it is less than 2000L/h.

F212 渦流量計を用いた湿り蒸気の流量測定における湿り度の影響(OS4 省エネルギー・コジェネ・ヒートポンプ)

F212 渦流量計を用いた湿り蒸気の流量測定における湿り度の影響(OS4 省エネルギー・コジェネ・ヒートポンプ)