Orifice Flowmeter Research Articles

EXPERIMENTAL INVESTIGATION AND CFD SIMULATION OF THE ORIFICE FLOW METER TO MEASURE TWO-PHASE FLOW

In this study, an investigation is conducted to examine various methods for measuring the two-phase flow of water and air. The two-phase flow loop and its equipment, including the orifice flow meter, were designed and manufactured in accordance with relevant standards. By employing the orifice flow meter in the two-phase flow loop and determining the total mass flow rate of the two-phase flow passing through it, the pressure drop of the orifice flow meter was determined for different values of the flow rate and volume fractions of the water and air phases in the two-phase flow. The Reynolds number of the two-phase flow ranged from 700 to 11000, while the air volume fraction ranged from 10% to 45%. We observed that, for the orifice flow meter, the slope of the discharge coefficient variation in relation to the two-phase flow Reynolds number was higher at low Reynolds numbers, where a laminar flow pattern was established. As the two-phase flow Reynolds number increased, the flow pattern transitioned from laminar to plug flow, resulting in a decrease in the slope. The orifice flow meter under two-phase flow conditions was simulated using computational fluid dynamics (CFD) with different turbulence models. The results indicated that the k-epsilon RNG turbulence model yielded more accurate results compared to other turbulence models. This study provides a foundation for the measurement of two-phase flows in the oil and gas industries.

Wearable Applicability of Respiratory Airflow Transducers: Current Approaches and Future Directions.

Advanced technologies employed in modern respiratory airflow transducers have exhibited powerful capabilities in accurately measuring respiratory flow under controlled and sedentary conditions, particularly in clinical settings. However, the wearable applicability of these transducers as face-mounted electronics for use in occupational and sporting activities remains unexplored. The present review addresses the critical wearability issue associated with current respiratory airflow transducers, including pneumotachographs, orifice flowmeters, turbine flowmeters, hot wire anemometers, ultrasound flowmeters, and piezoelectric airflow transducers. Furthermore, a comprehensive analysis and comparison of all factors that impact the wearable applicability of respiratory airflow transducers are conducted, considering dynamic accuracy, long-term usability, power consumption, calibration frequency, and cleaning requirements. The findings indicate that the piezoelectric airflow transducer stands out as a more viable option for wearables compared to other devices. We expect that this review will serve as a valuable engineering reference, guiding future research efforts in designing and developing wearable respiratory airflow transducers for ambulatory respiratory flow monitoring.

A 3D numerical model for the performance analysis of a differential pressure flow meter in transient conditions for liquid fuels

In the present paper, the metrological performance of a single-hole, sharped edge, and the orifice flow meter is numerically investigated employing different liquid fuels. Numerical investigations have been performed for a three-dimensional transient flow. Turbulence has been modeled employing the Realizable K-ε turbulence model, based on the Unsteady Reynolds-averaged Navier-Stokes (URANS). The present work is conducted in the context of the European SAFEST 20IND13 project, aimed at investigating the performance of the orifice flow meter numerical model in a wide range of temperatures, density, viscosity, and different liquid fuels. The numerical model, validated according to the ISO standard 5167-2 is employed to analyze the metrological performance of a test rig available at project partners’ laboratories and was aimed at reproducing the fuel consumption curve of a light and heavy transport vehicle.

标准孔板流量计上下游测量管维护方法研究

标准孔板流量计上下游测量管维护方法研究

The influence of flowmeters on rhinomanometry results and detection of nasal airflow asymmetry.

<b><br>Introduction:</b> Rhinomanometry is an otolaryngological diagnostic method used to determine airflow as a function of the pressure drop through the left and right nasal cavities. Airflow is measured using orifice flowmeters that attenuate the flow.</br> <b><br>Aim:</b> This paper describes the results of a study into the effects of flowmeter design on rhinomanometry results and detection of nasal airflow asymmetry.</br> <b><br>Material and methods:</b> Four flowmeters were examined using a 3D printed model of a human nose.</br> <b><br>Conclusions:</b> Each flowmeter interfered with the rhinomanometry results.</br&gt.

Design and Construction of a Device to Evaluate the Performance of Variable Orifice Flow Meters (VOFM)

This work presents a low-cost device for evaluating Variable Orifice Flow Meters (VOFM) used in medical mechanical ventilation applications. Specifically, the equipment was used to assess the impact of length and thickness on pressure drop for different flows in a rectangular geometry VOFM. A total of six VOFMs, with three different lengths and two different thicknesses, were evaluated. All VOFMs were stimulated with an airflow ranging from 0 L.min−1 to 90 L.min−1, with increments of approximately 2 L.min−1. The experiments conducted with the device showed a strong relationship between pressure drop ∆P and flow rate Q in the evaluated VOFMs, with two different zones: one exhibiting non-linear behavior and another showing linear behavior. The results suggest that increased length and decreased thickness lead to higher sensitivity. However, it is essential to reduce the cross-sectional area to mitigate nonlinear effects of the sensor.

Analysis of shift in discharge coefficient for contaminated multihole orifice flow meter

The aim of this paper is to provide a comprehensive numerical study of influence of contamination and multi-hole orifice (MHO) flow meter geometry on shift in discharge coefficient. In this research, authors analyzed steady, three-dimensional, turbulent flow of dry air through MHO flow meter with 3 different β parameters. Shift in discharge coefficient was calculated for 29 different combinations of contamination parameters for 7 contamination angles, 3 different Reynolds numbers and 3 β parameters. Numerical method that was used was finite volume method with SIMPLE algorithm and standard k-ε turbulence model. Grid sensitivity study was performed on four systematically refined numerical grids for MHO with contamination for all values of Reynolds number, all values of β parameters and 3 values of contamination angle. Obtained results were grid independent. Numerical results for MHO without contamination were compared with the experimental results found in the literature. It was found that contamination angle has most influence on shift in discharge coefficient. Also it was found that the contamination has influence on the change of pressure drop values, which directly affects the change of other parameters. Pressure drop and singular pressure loss coefficient of the orifice with contamination are smaller compared to the values for a pure orifice, whereby the measurement accuracy was reduced. It was found that the multi-hole orifice meter was less sensitive to the pressure drop changes due to the increasing of contamination angle in regards to the single-hole orifice meters.

Detection of Sensor Faults with or without Disturbance Using Analytical Redundancy Methods: An Application to Orifice Flowmeter.

Sensors and transducers play a vital role in the productivity of any industry. A sensor that is frequently used in industries to monitor flow is an orifice flowmeter. In certain instances, faults can occur in the flowmeter, hindering the operation of other dependent systems. Hence, the present study determines the occurrence of faults in the flowmeter with a model-based approach. To do this, the model of the system is developed from the transient data obtained from computational fluid dynamics. This second-order transfer function is further used for the development of linear-parameter-varying observers, which generates the residue for fault detection. With or without disturbance, the suggested method is capable of effectively isolating drift, open-circuit, and short-circuit defects in the orifice flowmeter. The outcomes of the LPV observer are compared with those of a neural network. The open- and short-circuit faults are traced within 1 s, whereas the minimum time duration for the detection of a drift fault is 5.2 s and the maximum time is 20 s for different combinations of threshold and slope.

Respiratory Rate Estimation during Walking and Running Using Breathing Sounds Recorded with a Microphone.

Emerging evidence suggests that respiratory frequency (fR) is a valid marker of physical effort. This has stimulated interest in developing devices that allow athletes and exercise practitioners to monitor this vital sign. The numerous technical challenges posed by breathing monitoring in sporting scenarios (e.g., motion artifacts) require careful consideration of the variety of sensors potentially suitable for this purpose. Despite being less prone to motion artifacts than other sensors (e.g., strain sensors), microphone sensors have received limited attention so far. This paper proposes the use of a microphone embedded in a facemask for estimating fR from breath sounds during walking and running. fR was estimated in the time domain as the time elapsed between consecutive exhalation events retrieved from breathing sounds every 30 s. Data were collected from ten healthy subjects (both males and females) at rest and during walking (at 3 km/h and 6 km/h) and running (at 9 km/h and 12 km/h) activities. The reference respiratory signal was recorded with an orifice flowmeter. The mean absolute error (MAE), the mean of differences (MOD), and the limits of agreements (LOAs) were computed separately for each condition. Relatively good agreement was found between the proposed system and the reference system, with MAE and MOD values increasing with the increase in exercise intensity and ambient noise up to a maximum of 3.8 bpm (breaths per minute) and -2.0 bpm, respectively, during running at 12 km/h. When considering all the conditions together, we found an MAE of 1.7 bpm and an MOD ± LOAs of -0.24 ± 5.07 bpm. These findings suggest that microphone sensors can be considered among the suitable options for estimating fR during exercise.

Soft sensor for an orifice flowmeter in presence of disturbances

Measurements using an orifice flowmeter are widely used in industry. In certain instances, the output of the flowmeter may be corrupted due to plate contamination, changes in fluid density, or incorrect insertion of the plate. This paper describes a method for estimating the correct output in the presence of such disturbances. First, a linear parameter-varying model of the orifice flowmeter is developed using data extracted from computational fluid dynamics simulations. The simulation and experimental output are found to have an average deviation of 6.5% and 3.49% in terms of the differential pressure and discharge coefficient, respectively. Observer-based estimators for the linear parameter-varying models are developed for different combinations of the settling time and maximum overshoot. These estimators enable the disturbance-induced output to be corrected close to the true value. The error in the disturbed output due to plate contamination is reduced from 45% to 0.82%. Similarly, the error due to an accidental change of plate decreases from 76% to 2.03%. Thus, the proposed estimator can be used to nullify the disturbances induced in the measurements from orifice flowmeters.

Parametric analysis of orifice plates on measurement of flow: A review

Flow measurement is a process of monitoring flow rate of fluids. Flow measurement is one of the critical processes in many industries, it is essential to carry out a detailed analysis of uncertainties associated with flow measurement. This paper attempts to understand the basics of existing flow measurement techniques and orifice flow meter in particular as it is widely used for measurement of flow due to its industry-friendly characteristics. A detailed review is presented in the paper to understand the dynamics of flow measurement, effects caused on the measurement due to variation in a physical dimension of the orifice like thickness of orifice plate, orifice-hole diameter, number of holes, etc. Discussion is also carried on to understand the influence of parameters like type of fluids, position and type of plate. The parametric effect on the performance of an orifice plate is validated using Computational Fluid Dynamics (CFD) for a better understanding of its dynamic nature.

Mach 4 Simulating Experiment of Pre-Cooled Turbojet Engine Using Liquid Hydrogen

This study investigated a pre-cooled turbojet engine for a Mach 5 class hypersonic transport aircraft. The engine was demonstrated under takeoff and Mach 2 flight conditions, and a Mach 5 propulsion wind tunnel test is planned. The engine is composed of a pre-cooler, a core engine, and an afterburner. The engine was tested under simulated Mach 4 conditions using an air supply facility. High-temperature air under high pressure was supplied to the engine components through an airflow control valve and an orifice flow meter, and liquid hydrogen was supplied to the pre-cooler and the core engine. The results confirmed that the starting sequence of the engine components was effective under simulated Mach 4 conditions using liquid hydrogen fuel. The pre-cooling effect caused no damage to the rotating parts of the core engine in the experiment.

Comparison of single-hole and multi-hole orifice energy consumption

Nowadays, with rising energy prices, energy efficiency is playing an important role in all industries. Differential pressure-based measuring instruments are still widely used instruments with orifice flow meters being the most popular ones. Due to its simplicity, reliability, and ease of maintenance, orifice flow meters are very common measuring instruments in many industries. As these instruments are differential pressure-based instruments, they are increasing energy costs due to increased pressure loss. Conventional single-hole orifice (SHO) flow meters have many advantages but also some disadvantages that are affecting energy efficiency. These disadvantages like higher pressure difference, slower pressure recovery, lower discharge coefficient can be overcome by multi-hole orifice (MHO) flow meters. Computational fluid dynamics (CFD) simulations were used to study energy consumption of both SHO and MHO with four different β parameters. Results showed MHO to be more energy efficient compared to SHO with same β parameter. These results are showing one more advantage MHO have compared to SHO, but further research is needed to make them a drop-in replacement.

Validation and assessment of different RANS turbulence models for simulating turbulent flow through an orifice plate

In the present study, numerical simulations using different Reynolds-Averaged Navier–Stokes (RANS) turbulence models are carried out to investigate the turbulent flow through the orifice plate at Reynolds number (Re) of 23000. The orifice thickness to pipe diameter ratio (t) and the orifice diameter to pipe diameter ratio (β) are fixed and equal to 0.1 and 0.5, respectively. The objective is to evaluate the behaviour of various RANS models with respect to the relevant flow parameters such as the pressure drop, velocity distributions and turbulence intensity profiles in the pipe by comparing the results with available published experimental data. The following turbulence models are studied: the k – ε, the k – ε Low Re, the k – ε RNG, the k – ε Realizable, the k – ω SST, the γ – SST, the EARSM and the k – ε Cubic models. It is found that based on the validation study of the flow through the orifice plate, the following models are in good agreement with experimental measurements: the k – ω SST, the γ – SST and the EARSM. They show a better performance than the k – ε model family in predicting the flow features which are important for the orifice flowmeter design.

Experimental study on the diagnosis of operation state of gas extraction pipeline based on pressure gradient method

ABSTRACT The working state of the gas drainage pipe network is the key to the safe drainage of underground mine gas. In order to quickly and accurately determine whether the pipe network is working normally, the flow law of the gas in the pipeline is studied. A diagnosis method of gas extraction pipeline by pressure gradient method is established. A gas drainage pipe network experimental platform is constructed. And the blockage and leakage of single pipe are carried out. The influence of air leakage of main pipe on negative pressure of branch pipe is studied, as well as the influence of negative pressure change of temporary pumping station on parallel pipe is explored. The method of image photography is proposed to calculate the pipeline flow, and the error is 2.7% compared with the orifice flowmeter. The results show that when the abnormalities exist in the extraction pipeline, the slope of the pressure curve corresponding to the abnormalities increases rapidly, the slope of the downstream curve is slightly larger than the slope of the upstream curve when the pipeline is leaking, and the slope of the downstream curve returns to the same as the slope of the upstream curve when the pipeline is blocked. The closer the location of the vacuum pump is to the air leakage, the faster the negative pressure of the vacuum pump decreases, and the less it affects the negative pressure of the branch circuit. When the downhole temporary pumping station extraction system is connected in series with the permanent pumping station extraction system on the ground, the temporary pumping station’s negative pressure value needs to be set reasonably, seriously affecting the extraction effect of the adjacent extraction pipeline. Finally, monitoring the gas drainage pipeline in Yuwu mine by pressure gradient method, it is found that the pressure drop slope at measuring points 6–7 is abnormal (−3 × 104), and the pressure drop slope of measuring points 7–8 returned to normal (−7 × 105), so it is judged that the drainage pipeline is blocked at 1300–1500 m away from the pump station.

Experimental study on effects of geometric and hydrodynamic parameters on performance of multi-holed orifice flowmeters

Multi-holed Orifices (MOs) are widely used in swirling, cavitating and developing flows to reduce pressure losses. This study focuses on analysis of MOs for developing turbulent flows. A large number of experiments were performed, exploring the number of holes (n), Equivalent Diameter Ratio (EDR), compactness ratio (C), plate thickness ratio (s/d) and upstream developing length (L/D) in the Reynolds number (ReD) range of 24,500–55,500. An empirical correlation of pressure loss coefficient and flow rate is formulated. It is observed that pressure loss coefficient decays with the fourth power of EDR. A comparative study of the experimental data with the literature is presented to ensure consistency and reliability.

Effect of conical angle on the hydraulic properties of orifice plate flows: A numerical approach

Orifice flowmeters are widely used in industry due to their simple design, ruggedness, and easy installation. However, high-pressure losses, measurement accuracy, and long pipe length requirements are still significant concerns. Typically, conical entry orifice plates at a 45-degree conical angle are recommended by orifice standards, especially for low Reynolds numbers instead of the sharp-edged orifice plates, which pose stability. The primary goal here is to develop the conical entry orifice plates further over a broader range of Reynolds numbers. In this case, a 45-degree conical angle may seem questionable since the optimization of conical angles has not been studied so far. To clarify that point and reach the new technical data about the conical entry orifice plates, orifice plates in different orifice diameter ratios (0.4, 0.5, 0.63) and beveled with different conical angles (15°, 30°, 45°) were tested numerically through water flow simulations inside a pipe with an inner diameter of 50.8 mm at different Reynolds numbers (5000,18,400, 91,100, 240,000).According to the analysis made, the 30-degree conical angle orifice plate was the best in reducing pressure losses, resulting in pressure losses 37–52% less than that of sharp-edged orifice plates in the min-max range. Furthermore, it reduced the pressure losses by 13–21 % more than that of the 45-degree conical angle. These last outcomes indicate that current orifice standards needs a modification into the recommended conical angles. Through these findings, pressure losses in multi-hole plate flow conditioners can be reduced considerably when the holes are beveled at the 30-degree conical angle.Also in the study, the axial characteristic lengths relevant to recirculation region, flow recovery and vena contracta were predicted approximately, along with the derived numerical correlations resulting with constants. Moreover, the effect of orifice plates exposed to an upstream distorted velocity profile on orifice flows was tested numerically. According to this evaluation, the lowest measurement errors were observed at the 30-degree conical angle orifice plate, about 30–70 % less than that of the sharp-edged orifice plate in the min-max range.

Evaluation of multi-holed orifice flowmeters under developing flow conditions – An experimental study

This study focuses on multi-holed orifice plates, which have superior flow measuring characteristics as compared to their conventional counterparts. However, literature is scant on quantitative parametric investigations. In this experimental study, the performance of a multi-holed orifice plate is evaluated for variable number of holes (n), equivalent diameter ratio (EDR), compactness ratio (C), plate thickness ratio (s/d) and upstream developing length (L/D) in developing flow regimes for the Reynolds number range of 24,500–55,500 by using Central Composite Design. A total number of 324 experiments were performed. It was found that EDR has the most significant effect on pressure loss coefficient, followed by ‘n’ and ‘C’. Moreover, it was found out that single orifice (SO) and multi-holed orifice (MO) have almost the same pressure losses for the same value of EDR/β. However, flow develops quickly for MOs. Higher values of coefficient of discharge were observed in the case of MOs as compared to the SOs with little effect of upstream disturbances. The effect of developing length is significant on the accuracy of orifice meter. However, when the multi-holed orifice plates are installed at 2D upstream length, the effect of upstream disturbances are diminished. This result provides the flexibility of installation, which means that multi-holed orifices can be installed at 2D. The experimental data is in good agreement with literature. Finally, an optimum orifice plate (5,0.4,0.7) was selected for flow developing region with minimum pressure loss coefficient based upon the experimental results.

Multi-Objective Optimization of Multistage Pump Balance Drum System Based on BP Neural Network and Genetic Algorithm

The axial force balancing capacity of a balance drum is a key factor affecting the life of multi-stage centrifugal pumps. In this paper, a double shell segmental multistage pump is taken as the research object. The hydraulic performance and axial force performance are set as the optimization objectives, and the performance data are obtained by numerical simulation with FLUENT software. The BP neural network is used to establish the prediction model of structural parameters of the balance system, hydraulic performance and residual axial force performance, and it is used as the adaptive value evaluation model of genetic algorithm to solve the optimal value in the sample space. The results show that the radial clearance of the balance drum and the balance tube orifice flowmeter, the axial width of the balance cavity are the significant factors affecting the hydraulic performance and axial force performance of the multistage pump. When the radial clearance of the balance drum is 0.1mm, the clearance of the orifice flowmeter is 1.95mm, and the axial width of the balance cavity is 55mm, the multi-stage pump has the best hydraulic performance and the smallest residual axial force. The vortex band in the balance cavity can increase the amount of the fluid spin and enhance the axial force balancing capacity of the balance drum. The greater the area occupied by the negative high-rotation fluid in the balance cavity, the stronger the ability of the balance drum to balance the axial force. The test results show that compared with the prototype multistage pump, at nominal flow rate, the head and efficiency of the optimized model are increased by 0.71% and 1.63% respectively, and the bearing temperature and vibration speed of the multi-stage pump are significantly reduced.

Investigation on different scenarios of two-phase flow measurement using Orifice and Coriolis flow meters: Experimental and modeling approaches

In this study, various methods for multiphase flow metering were introduced. These techniques include measurement of gas-liquid average density by a Coriolis flow meter and determining the gas volume fraction by discharge coefficient of an orifice plate. Application of Orifice plate and Coriolis flow meters were investigated for gas-liquid flow metering. The principle of using these instruments as single-phase flow meters, for measurement of the two-phase flow was not focused in previous studies. In the second part, gas volume fraction was predicted by a soft sensor. Variation of Coriolis meter factor with gas volume fraction and Reynolds number was studied. Moreover, changes of pressure drop and discharge coefficient of Orifice with Reynolds number was investigated. On the other hand, 250 data sets were collected to develop a soft sensor using 2-layer and 3-layer neural networks optimized by genetic algorithm and Least Square Support Vector Machine. Increasing Reynolds number led to decrease in Coriolis meter factor. Among various computational intelligence methods, 3-layer neural network was the best, with mean square error and mean absolute percent error of 0.91% and 3%, respectively and computation time of 0.0001 s.