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The purpose of this paper is to review three decades of the literature on flow measurement and propose issues to advance research on the measurement of social flow at work.

In a systematic literature review, the authors analyzed 143 articles published in the first three decades (1983–2013) of scholarly publications on flow measurement, of which 84 articles used scales to measure flow and 16 articles used scales to measure flow at work.

The main findings are: flow is frequently measured in association with other constructs or by means of proxies; flow measurement is highly dependent on a study’s purposes and context; flow is mostly studied at the level of the individual and, when studied beyond the individual, the measurement of flow in groups is simplified as an aggregation of individual-level measures; and social flow at work is an underresearched construct that nevertheless impacts organizations in important ways, thus deserving a specific research agenda.

The first limitation refers to the databases included in the review. There is always the possibility that important works were ignored. Another limitation is that the coding procedure was highly dependent on the authors’ discretion, as it did not include independent coding and formal assessment of agreement among coders. But the greatest limitation may refer to our very perspectives on flow, flow measurement and social flow at work, as they are highly attached to current models instead of seeing the issues with different lenses. This limitation is also present in the literature.

Reviewing three decades of scholarly publications on how flow has been measured contributes to organizations in their planning for person-job fit. The measurement of flow can reveal if and when flow correlates with personal characteristics and organizational events, thus serving to inform initiatives on personnel development, acculturation and job design. However, considering that flow as a social phenomenon has been conceived in superficial terms, that a vast number of empirical studies were developed with non-professional subjects, and that flow measurement involves significant adaptations to each situation, organizations are thus advised to be careful in adopting extant instruments.

This study provides a rich account on how flow measurement has been addressed in the scholarly literature, and it calls attention to research opportunities on social flow at work.

Owing to the technology growth, especially in Microsystems technology and Nanotechnology, new products will provide new ways to sense variables that are crucial for product improvement and system reliability. A big concern of the scientific community is the measurement of low level flow measurements, especially for the biomedical and/or systems on a chip approaches.Design/methodology/approach – A new flow meter concept design consists of a surface micromachined sensor having an optical high reflective mirror made of gold, which is attached to unique cantilever designs that bend due to the drag force of mass flow. The bending of the cantilevers produces the mirror to approach/depart from an optical fiber end‐tip. The reflective light to fiber is modulated using a Fabry‐Perot interferometry technique to determine the mirror separation to the fiber, which corresponds to the mass flow.Findings – The new concept design shows a big potential approach to measure low flow measurements for air, gas and liquids of low viscosity. The results of this concept, through finite element analysis, show that the material used to build the sensor, makes them excellent candidates for fabrication. The stresses of the materials and allowable (readable) bending are among the tolerances of such materials/construction‐design. The sensor is not affected by electromagnetic interference and does not require electrical currents to sense, i.e. it is perfectly suited for biomedical and low mass‐flow sensing such as lab‐on‐chip applications.Originality/value – Among all approaches to sense low flow measurements, most of them need either “big” turbine approaches (dimensions over 1 cm diameter), or the need of an electrical approach needed in the end measurement sensor. This work proposes a non‐electrical approach.

A prototype gas prover was constructed to serve as the Italian primary standard for gas flow rates in the range 0.1 ml/min to 2 l/min. The new prover is used to calibrate high‐quality industrial standards, as well as the MFCs used in microelectronic fabrications and preparation of reference gas mixtures.Design/methodology/approach – The prover measures gas volume transfers caused by displacements of a 120 mm dia. motor‐operated piston, which is introduced into a temperature‐controlled chamber containing up to 3 l of the required working gas at near ambient conditions. Gas delivery is made at constant rate, whereas possibly variable incoming flows are measured at constant pressure. Displacements of the piston are measured by an optical interferometer.Findings – The analysis shows that standard uncertainty ranges between 0.013 and 0.03 percent. Owing to the very accurate control and measurement of both pressures and temperatures, these figures refer equally to volume and mass flowrate. Experimental comparisons with similar national standards at LNE‐France and NIST‐USA confirmed the consistency of measurement results in the three Nations.Research limitations/implications – The gas prover should be used with inert gases only.Practical implications – The national industrial gas standards and the best flow transducers can now be calibrated accurately down to unprecedented flowrate values.Originality/value – The need for measurement of extremely low gas flows is quite recent, therefore possibly less than ten primary national standards are available today worldwide. Several completely different principles and designs have been developed; description of design and performance of each instrument is important to assess their respective merits. The described apparatus is innovative as regards measurement range, accuracy and control techniques.

Pressure, being one of the key variables investigated in scientific and engineering research, requires critical and accurate measurement techniques. With the advancements in materials and machining technologies, there is a large leap in the measurement techniques including the development of micro electromechanical systems (MEMS) sensors. These sensors are one to two orders smaller in magnitude than traditional sensors and combine electrical and mechanical components that are fabricated using integrated circuit batch-processing technologies. MEMS are finding enormous applications in many industrial fields ranging from medical to automotive, communication to electronics, chemical to aviation and many more with a potential market of billions of dollars. MEMS pressure sensors are now widely used devices owing to their intrinsic properties of small size, light weight, low cost, ease of batch fabrication and integration with an electronic circuit. This paper aims to identify and analyze the common pressure sensing techniques and discuss their uses and advantages. As per our understanding, usage of MEMS pressure sensors in the aerospace industry is quite limited due to cost constraints and indirect measurement approaches owing to the inability to locate sensors in harsh environments. The purpose of this study is to summarize the published literature for application of MEMS pressure sensors in the said field. Five broad application areas have been investigated including: propulsion/turbomachinery applications, turbulent flow diagnosis, experimentalaerodynamics, micro-flow control and unmanned aerial vehicle (UAV)/micro aerial vehicle (MAV) applications.

The first part of the paper deals with an introduction to MEMS pressure sensors and mathematical relations for its fabrication. The second part covers pressure sensing principles followed by the application of MEMS pressure sensors in five major fields of aerospace industry.

In this paper, various pressure sensing principles in MEMS and applications of MEMS technology in the aerospace industry have been reviewed. Five application fields have been investigated including: Propulsion/Turbomachinery applications, turbulent flow diagnosis, experimental aerodynamics, micro-flow control and UAV/MAV applications. Applications of MEMS sensors in the aerospace industry are quite limited due to requirements of very high accuracy, high reliability and harsh environment survivability. However, the potential for growth of this technology is foreseen due to inherent features of MEMS sensors’ being light weight, low cost, ease of batch fabrication and capability of integration with electric circuits. All these advantages are very relevant to the aerospace industry. This work is an endeavor to present a comprehensive review of such MEMS pressure sensors, which are used in the aerospace industry and have been reported in recent literature.

As per the author’s understanding, usage of MEMS pressure sensors in the aerospace industry is quite limited due to cost constraints and indirect measurement approaches owing to the inability to locate sensors in harsh environments. Present work is a prime effort in summarizing the published literature for application of MEMS pressure sensors in the said field. Five broad application areas have been investigated including: propulsion/turbomachinery applications, turbulent flow diagnosis, experimental aerodynamics, micro-flow control and UAV/MAV applications.

Sediment measurement is usually accessible on a periodic or distinct basis. The measurement of sediment (suspended and bedload), especially in the field, is vital in keeping essential data of sediment transport and deposition. Various techniques for measuring sediment have been used over time each with its merits and demerits. The techniques discussed in this paper for suspended sediment include bottle, acoustic, pump, laser diffraction, nuclear and optical. Other techniques for bedload measurement are; River bedload trap (RBT), CSU/FU bedload trap, Helley–Smith, Polish Hydrological Services (PIHM) device, pit and trough, vortex tube, radioactive traces and bedload–surrogate technologies. However, the choice of technique depends on multiple factors ranging from budget constraint, availability of equipment, manpower and data requirement. The purpose of this paper is to present valuable information on selected techniques used in sediment measurement, to aid researchers/practitioners in the choice of sediment measurement technique.

This paper presents a general review of selected field techniques used in sediment measurement (suspended and bedload). Each techniques mode of operation, merits and demerits are discussed.

This paper highlights that each technique has its peculiar merits and demerits. However, two techniques are generally preferred over others; the bottle sampling and the Helley–Smith sampler for measuring suspended and bedload sediment. This is because the applicability of these techniques is quite widespread and time-tested.

This review paper provides an in-depth description and comparison of selected existing field sediment measurement techniques. The objective is to ease decision-making about the choice of technique, as well as to identify the suitability and applicability of the chosen technique.

The purpose of this paper is to develop a new vibration probe sensor for measurement of particle mass flow rate in gas–solid two phase flow.

A new vibration probe sensor based on polyvinylidene fluoride (PVDF) piezoelectric film is designed. The particle impact model according to Hertz contacting theory is presented. The average amplitude, standard deviation and spectral peak at the natural frequency of the probe (21.2 kHz) of the signals acquired through experiments are chosen as characteristic quantities for further analysis.

Through experimental study of relation between three characteristic quantities and the mass flow rate and air flow velocity, a good regularity is found in the average amplitude and the spectral peaks at natural frequency of the probe. According to the particle impact model, the structure of quantitative model is built and parameters of two models are calculated from experimental data. Additionally, tests are made to estimate mass flow rate. The average errors are 5.85 and 4.26 per cent, while the maximum errors are 10.81 and 8.65 per cent. The spectral peak at natural frequency of the probe is more applicable for mass flow rate measurement.

The sensor designed and the quantitative models established may be used in dilute phase pneumatic conveying lines of coal-fired power plants, cement manufacturing facilities and so on.

First, the new sensor is designed and the quantitative models are established. Second, the spectral peak at natural frequency of the probe is found that can be used for measurement of mass flow rate.

The purpose of this paper is to view the flow concentration of the flowing material in a pipeline conveyor.

Optical tomography provides a method to view the cross sectional image of flowing materials in a pipeline conveyor. Important flow information such as flow concentration profile, flow velocity and mass flow rate can be obtained without the need to invade the process vessel. The utilization of powerful computer together with expensive data acquisition system (DAQ) as the processing device in optical tomography systems has always been a norm. However, the advancements in silicon fabrication technology nowadays allow the fabrication of powerful digital signal processors (DSP) at reasonable cost. This allows the technology to be applied in optical tomography system to reduce or even eliminate the need of personal computer and the DAQ. The DSP system was customized to control the data acquisition of 16 × 16 optical sensors (arranged in orthogonal projection) and 23 × 23 optical sensors (arranged in rectilinear projections). The data collected were used to reconstruct the cross sectional image of flowing materials inside the pipeline. In the developed system, the accuracy of the image reconstruction was increased by 12.5 per cent by using new hybrid image reconstruction algorithm.

The results proved that the data acquisition and image reconstruction algorithm is capable of acquiring accurate data to reconstruct cross sectional images with only little error compared to the expected measurements.

The DSP system was customized to control the data acquisition of 16 × 16 optical sensors (arranged in orthogonal projection) and 23 × 23 optical sensors (arranged in rectilinear projections).

The sensitivity of differential‐pressure flow meters to the quality of the approaching flow continues to be a cause for concern to flow meter manufacturers and users. Distortions to the approaching velocity profiles generated by pipe fittings and installations located upstream of a flow meter, can lead to considerable errors in flow metering. This cannot be ignored because of the likely cost and process efficiency implications. This paper describes the effects of various entrance flow velocity profiles on the performance of an orifice flow meter with and without flow conditioning. Asymmetric swirling velocity profiles were generated by a ball valve. These caused significant shifts to the meter’s calibration. The use of a vaned‐plate flow conditioner, consisting of six vanes attached to a 70 per cent porosity plate, greatly improved the performance of the meter. Thus, the device can be used as part of a flow metering package that will have considerably reduced installation lengths. The less‐sophisticated NEL plate proved to be a good flow straightener, i.e. a good swirl remover, but was not an efficient flow conditioner.

The purpose of this study is to deal largely with the influence of temperature variation on the measurement accuracy of transit-time ultrasonic flowmeter.

The causes of measurement error due to temperature are qualitatively and quantitatively analyzed, and a mathematical model is established. The experimental data are processed and analyzed, and the temperature compensation coefficient of flow measurement is obtained.

The experimental results show that the flow measurement results by temperature compensation are helpful in improving the measurement accuracy of the ultrasonic flowmeter.

This study has certain application value, which can provide theoretical support for the design of high-precision ultrasonic flowmeters and design guidance.

It is worth emphasizing that there are few research studies on the influence factors of temperature. This paper focuses on the influence of the temperature change on the flowmeter that is modeled, and the high precision flow parameter test system is designed based on the established model.

The cross‐correlation flow measurement technique, applied for measuring the coolant flow rate in a nuclear reactor, was calibrated with the use of numerical simulations of turbulent flow. The three‐dimensional domain was collapsed into two dimensions. With a two‐dimensional calculation of steady‐state flow with transient thermal characteristics the response of thermocouples to a temperature variation was calculated. By cross‐correlating the calculated thermocouple responses, the link between total flow rate and measured transit times was made. The reliability of the calibration was estimated at ±4.6%. In addition, a measured velocity profile effect was successfully predicted.