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The purpose of this paper is to assess state-of-the-art techniques for quantifying flow distortion in the inlets of turbofan engines, particularly with respect to the prospects for future flight applications.

To adequately characterize the flow fields of complex aircraft inlet distortions, the author has incorporated laser velocimetry techniques, namely, stereoscopic particle image velocimetry (PIV) and Doppler velocimetry based on filtered Rayleigh scattering (FRS), into inlet distortion studies.

Overall, the results and experience indicate that the pathway for integration of FRS technologies into flight systems is clearer and more robust than that of PIV.

While always a concern, the topic of inlet distortion has grown in importance as contemporary airframe designers seek extremely compact and highly integrated inlets. This research offers a means for gaining new understanding of the in situ aerodynamic phenomena involved with complex inlet distortion.

This paper presents unique applications of turbofan inlet velocimetry methods while providing an original assessment of technological challenges involved with progressing advanced velocimetry techniques for flight measurements.

The purpose of this paper is to apply negative thermal coefficient (NTC) thick film segmented thermistors (TFSTs) in a micro‐flow sensor for water.

A TFST is printed using NTC paste based on nickel manganite. The resistance of this thermistor is measured in a climatic chamber and the resulting curves are calibrated. A micro‐flow sensor is designed using a self‐heated segmented thermistor. The sensing principle is based on heat loss depending on the water flow intensity through the capillary. Water flow calibration is performed. The sensor sensitivity, inertia, and stability are analyzed.

The micro‐flow sensor exhibits good stability, suitable sensitivity, and inertia for integral measurements of water flow.

Advantages of a micro‐flow sensor using a TFST include low energy consumption, simple measuring procedure, and passive electronics.

This paper describes initial work on a micro‐flow sensor for water using TFSTs.

Thermal flow sensors with a wide dynamic range are at present not available in spite of the large demand which exists for such sensors in practical fluid flow measurements. In this paper, it is shown that the velocity range of a “time‐of‐flight” thermal flowmeter for slowly changing flows can be increased by using wires (or other heating/sensing elements) with large thermal inertia (time constant) and heating the sending wire with a continuous sinusoidal current, instead of discrete, very short, square‐wave pulses as in the usual pulsed‐wire anemometer. The device described here uses two parallel wires of 12.5μm diameter and its usable speed range is 0.05 to 25m/s. Although the present thermal flowmeter can be applied as a point measurement device, the main applications are in pipe flow, especially at very low flow rates. The high sensitivity at low flow rates makes the device especially suitable for this purpose.

The purpose of this study is to contribute to the literature on team management and flow theory by framing shared flow in teams (SFT) as a unique construct of much interest for team performance, as well as by proposing team vibration as a metaphor and measurable property of SFT.

An inductive approach is used to identify the occurrence of SFT by means of team vibration, and scale development procedures are used to offer an instrument to measure team vibration.

The current state of knowledge does not allow researchers and team leaders to assume that flow in teams depends on team members being in full flow too. Accordingly, it is shown that SFT is an emergent phenomenon of the complex interaction of team members, thus not corresponding to the mere aggregation of flow of individual team members. Moreover, it is also shown that the emergent property of team vibration is an efficient surrogate measure for SFT because it enables better communication in measurement.

Team managers should hire professionals that contribute to high levels of vibration in teams because this is expected to leverage desirable team processes and outcomes. Such individuals possess an ideal balance of individual and group focus. However, the authors warn that managers should be careful in assuming that individuals in full state of flow are necessary for the occurrence of flow in teams.

This study frames SFT as a unique construct in the literature of flow in groups, in addition to developing a metaphor and surrogate measure (team vibration) and a measurement instrument.

The importance of tourism for France's economy and society means that proper knowledge of tourism flows is essential. But designing a measuring system and periodic gathering of statistical data raise several difficulties. First, tourism is, by definition, based on movement, and all phenomena involving movement are difficult to measure. Second, there are many different forms of tourism, including holidays and business trips, short and long stays and so forth. Third, the notion of tourism flows has different meanings for those in charge of road, rail or air traffic management, and for those in charge of tourist visits.

This paper first discusses the ambiguities of the notions used in tourism studies. It emphasises the distinction between tourist flows along transportation routes and those in specific places. It then reviews the proper calculation rules for each of the geographical objects used for measuring tourism phenomena, which are primarily lines and areas. It also addresses some of the problems raised by the failure to comply with these rules in published information.

Third, this paper presents the various systems used to measure tourist flows and inflows, and discusses their usefulness and limitations, before discussing some new developments in the field.

Finally, it examines the potential value of modern communication technologies for mobility studies. More specifically, it raises the issue of striking the right balance between statistical accuracy and individual freedom.

The asymmetry of the velocity profile caused by geometric deformation, complex turbulent motion and other factors must be considered to effectively use the flowmeter on any section. This study aims to better capture the flow field information and establish a model to predict the profile velocity, we take the classical double elbow as the research object and propose to divide the flow field into three categories with certain common characteristics.

The deep learning method is used to establish the model of multipath linear velocity fitting profile average velocity. A total of 480 groups of data are taken for training and validation, with ten integer velocity flow fields from 1 m/s to 10 m/s. Finally, accuracy research with relative error as standard is carried out.

The numerical experiment yielded the following promising results: the maximum relative error is approximately 1%, and in the majority of cases, the relative error is significantly lower than 1%. These results demonstrate that it surpasses the classical optimization algorithm Equal Tab (5%) and the traditional artificial neural network (3%) in the same scenario. In contrast with the previous research on a fixed profile, we focus on all the velocity profiles of a certain length for the first time, which can expand the application scope of a multipath ultrasonic flowmeter and promote the research on flow measurement in any section.

This work proposes to divide the flow field of double elbow into three categories with certain common characteristics to better capture the flow field information and establish a model to predict the profile velocity.

The use of pneumatic conveying of solid bulk over long distance has become a popular technique due to low operational cost, low maintenance requirement, layout flexibility and ease of automation. The purpose of this paper is to identifity the flow regime in a pneumatic conveyor system by electrodynamic sensor placed around the pipe using fuzzy logic tools.

Electrical charge tomography is used to detect the existence of inherent charge on the moving particles through the pipe. Linear back projection algorithm and filtered back projection algorithm are employed to produce tomography image. Baffles of different shapes are inserted to create various flow regimes, such as full flow, three quarter flow, half flow and quarter flow. Fuzzy logic tools are used to identify different flow regimes and produce filtered back concentration profiles for each flow regime.

The results show significant improvement in the pipe flow image resolution and measurement.

This paper presents a flow identifier method using electrical charge tomography and fuzzy logic to monitor solid particles flow in pipeline.

A survey is made of the instruments and methods used to measure total and static pressure and direction in three‐dimensional flow. Comparative tests in a towing tank of two designs of live‐orifice pitot‐type probe showed the advantage, within a limited range of flow inclination, of the instrument with independent static pressure orifices. Speed and angle of flow characteristics are Riven for these two probes, which differed in the shape of head.

Through a literature review, we found four potential research topics that are rarely studied in the extant literature, i.e. the missing link between web site quality and flow, an integrative relationships between web site quality, flow, customer satisfaction, and relationship intention even though part of the integrative relationships have been investigated in the previous studies, those flow‐related consumer behaviors in C2C e‐marketplaces, and cross‐national studies on the flow‐related consumer behaviors in the East‐Asian domain. Thus, we attempted to explore the relationships between web site quality, flow, customer satisfaction, and relationship intention in Chinese and Korean C2C e‐marketplaces as well as their cross‐national similarities and differences.

In all, 212 Chinese and 219 Korean online shoppers were surveyed to conduct the above research agenda by structural equation modeling.

Web site quality had some effect on flow and satisfaction in both countries, but different results between the countries were found for the dimensions of web site quality. Flow has a positive impact on satisfaction, but the effect in China was greater than that in Korea. Both flow and satisfaction had a positive effect on relationship intention in the two countries.

There has been little research that addressed the above four research topics respectively or in combination. This study investigates the integrative model between web site quality and flow‐related consumer behaviors in C2C e‐marketplaces. The paper provides empirical evidence of online consumer behaviors in China and Korea, which will help global e‐commerce managers/practitioners in their development of strategies and tactics for the East‐Asian markets.

A solution to increase the energy production rate of the wind turbine is proposed by forcing more air to move through the turbine working section. This can be achieved by equipping the rotor with a diffusing channel ended with a brim (diffuser augmented wind turbine – DAWT). The purpose of this paper is to design an experimental stand and perform the measurements of velocity vector fields through the diffuser and power characteristic of the wind turbine.

The experiments were carried out in a small subsonic wind tunnel at the Institute of Turbomachinery, Lodz University of Technology. An experimental stand design process as well as measurement results are presented. Model size sensitivity study was performed at the beginning. The experimental campaign consisted of velocity measurements by means of particle image velocimetry (PIV) and pneumatic pitot probe as well as torque and rotational velocity measurements.

Characteristics (power coefficient vs tip speed ratio) of the bare and shrouded wind turbine were obtained. The results show an increase in the wind turbine power up to 70-75 per cent by shrouding the rotor with a diffuser. The mechanisms responsible for such a power increase were well explained by the PIV and pneumatic measurement results revealing the nature of the flow through the diffuser.

Experimental stand for wind turbine rotor testing is of a preliminary character. Most optimal methodology for obtaining power characteristic should be determined now. Presented results can serve as good input for choice of stable and reliable control system of wind turbine operational parameters.

A 3 kW DAWT is being developed at the Institute of Turbomachinery, Lodz University of Technology. Aim of the study is to design a compact and smart wind turbine optimised for low wind speed conditions. Developed wind turbine has a potential to be used as an effective element within a net of distributed generation, e.g. for domestic use.

Research carried out is the continuation of theoretical study began in 1970s. It was also inspired by practical solutions proposed by Japanese researchers few years ago. Presented paper is the summary of work devoted to optimisation of the DAWT for wind conditions in the region. Original solution has been applied, e.g. for experimental stand design (3D printing application).