Flow Facility Research Articles

High viscosity effects on characteristics of oil and gas two-phase flow in horizontal pipes

The flow characteristics of high viscosity oil and gas flow show several significant differences with those of low viscosity liquid. Effects of high viscosity oil on characteristics of oil and gas flow are identified. The present experiments are performed on the flow facility which consists of a test section of 26mm ID and a 5.5m long horizontal pipe. A range of liquid viscosity from 1000cP to 7500cP is investigated. The superficial oil and gas velocities vary from 0.06m/s to 0.5m/s and from 0.3m/s to 12.0m/s respectively. The resulting flow patterns are identified by Electrical Capacitance Tomography (ECT) and confirmed by videos recorded during the experiments. The pressure and liquid holdup data are obtained by using pressure transducers and ECT system. The experimental results are compared with existing models and show significant discrepancies between low and high viscosity liquid and gas flows.

Is World Really Borderless? - An Analysis from the Fourth World Perspective

This research paper is an attempt to examine the empirical reality of the argument leveled for and against the existence of borderless world. This examination is the prime objective of this paper. The paper is primarily conceptual in nature. The use of secondary data as a prime source of analysis has helped understand the way the trade is concentrated in various trading blocks. Since the author is convinced about the fact that the ‘Fourth World’ is largely precluded from the expected scenario and the facility of free flow of goods and services, a case study method is used to understand the significant issues of the ‘Fourth World’ countries. The first part has discussed a theoretical framework that consists of the idea of borderless world. In addition to this, a Theory of Trading Blocks is incorporated in the first part of this paper. The second part of this paper includes an analytical framework which looks into the nature of the Fourth World and has also discussed the African continent as a case against the proposition of the possibility of the world being borderless or otherwise. The third part of this paper includes implications, conclusions and recommendations which make a summary evaluation of the proposition To examine the research question ‘Is World Really Borderless?’ and the hypothesis ‘yes, it is partially borderless’, this paper, in its first part, has examined the concept of ‘borderless world developed by Kenichi Ohame (Ohame, 1990, 99). In addition to this theoretical framework, the author has used ‘A Theory of Trading Blocks’ to understand how and to what extent countries trade in blocks and as such what implications it has on the idea of the world being borderless. This part includes the secondary data on ‘regionalization of trade and high concentration ratios of trade carried out within a boundary of a trading block. In its second part, the research paper has enquired the issue of the present state of the Fourth World in the context of the possibility of it being a part of global integration. To prove that the hypothesis is partially true, the author has discussed the case of the African continent to illustrate the relative position of the Fourth World in today’s much debated idea of economic integration. In its third part a conclusion is drawn which states that there are definite efforts made by countries towards making this world borderless but such efforts are lesser than required and the Fourth World is yet to be integrated into the mainstream of borderless and much comprehensive economic transactions.

Turbulent pipe flow downstream a 90° pipe bend with and without superimposed swirl

In the present work, the turbulent flow downstream a 90° pipe bend is investigated by means of stereoscopic particle image velocimetry. In particular, the three dimensional flow field at the exit of the curved pipe is documented for non-swirling and swirling flow conditions, with the latter being generated through a unique axially rotating pipe flow facility. The non-swirling flow was examined through snapshot proper orthogonal decomposition (POD) with the aim to reveal the unsteady behaviour of the Dean vortices under turbulent flow conditions, the so-called “swirl-switching” phenomenon. In respect to the swirling turbulent pipe flow, covering a wide range of swirl strengths, POD has been employed to study the effect of varying strength of swirl on the Dean vortices as well as the interplay of swirling motion and Dean cells. Furthermore, the visualised large scale structures in turbulent swirling flows through the bend are found to incline and tear up with increasing swirl intensity. The present time-resolved, three component, experimental velocity field data will provide a unique and useful database for future studies; in particular for the CFD community.

Protection from autoimmune nephritis in mice transgenic for BAFF, but lacking CD19

Event Abstract Back to Event Protection from autoimmune nephritis in mice transgenic for BAFF, but lacking CD19 Kirsten A. Fairfax1* and Fabienne MacKay1 1 Monash University, Australia B cell activating factor belonging to the TNF family (BAFF or BLys) is required for B cell survival and maturation. However, mice transgenic for BAFF (BAFFTg) develop spontaneous autoimmunity, resembling Systemic Lupus Erythematosus (SLE), in a T cell-independent manner. The autoantibodies which trigger disease in BAFFTg mice, are produced by marginal zone (MZ) and B1 cells, but not follicular B cells. Experiments using BAFFTg splenectomized mice suggested that it was not MZ or B1a B cells, but rather B1b B cells that were important in the development of autoimmune nephritis. We have developed a mouse cross between BAFFTG and CD19 knockout (ko) mice, in which MZ, B1a and B1b B cells are reduced. We observed that BAFFTgxCD19ko mice had reduced titres of autoantibodies compared to BAFFTg mice, and these mice resembled CD19ko animals with respect to autoantibody development. The BAFFTgxCD19ko animals were also protected from the splenomegaly observed in the BAFFTg animals. In aged mice BAFFTg display complement deposition in the glomeruli within the kidney, whilst BAFFTgxCD19ko were protected from this (as were the CD19ko mice). In addition, the BAFFTg glomeruli were larger, and more segmented than the BAFFTgxCD19ko, both signs of impaired function. Together these results point towards the pathogenic role of B1b B cells in autoimmune nephritis. This work also raises the prospect that targeting CD19 in SLE patients may prove efficacious. Acknowledgements We would like to acknowledge the Monash MicroImaging Facility, the AMREP Flow facility, the AMREP animal facility and the Baker Institute for allowing us to use the Cobas instrument. Keywords: Autoimmunity, BaffTg, Lupus Nephritis, B1 Cells, MZ B cells Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Immune-mediated disease pathogenesis Citation: Fairfax KA and MacKay F (2013). Protection from autoimmune nephritis in mice transgenic for BAFF, but lacking CD19. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.00930 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Jun 2013; Published Online: 22 Aug 2013. * Correspondence: Dr. Kirsten A Fairfax, Monash University, Melbourne, Australia, kirsten.fairfax@monash.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Kirsten A Fairfax Fabienne MacKay Google Kirsten A Fairfax Fabienne MacKay Google Scholar Kirsten A Fairfax Fabienne MacKay PubMed Kirsten A Fairfax Fabienne MacKay Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Optimization of environmental management strategies through a dynamic stochastic possibilistic multiobjective program

Greenhouse gas (GHG) emissions from municipal solid waste (MSW) management facilities have become a serious environmental issue. In MSW management, not only economic objectives but also environmental objectives should be considered simultaneously. In this study, a dynamic stochastic possibilistic multiobjective programming (DSPMP) model is developed for supporting MSW management and associated GHG emission control. The DSPMP model improves upon the existing waste management optimization methods through incorporation of fuzzy possibilistic programming and chance-constrained programming into a general mixed-integer multiobjective linear programming (MOP) framework where various uncertainties expressed as fuzzy possibility distributions and probability distributions can be effectively reflected. Two conflicting objectives are integrally considered, including minimization of total system cost and minimization of total GHG emissions from waste management facilities. Three planning scenarios are analyzed and compared, representing different preferences of the decision makers for economic development and environmental-impact (i.e. GHG-emission) issues in integrated MSW management. Optimal decision schemes under three scenarios and different pi levels (representing the probability that the constraints would be violated) are generated for planning waste flow allocation and facility capacity expansions as well as GHG emission control. The results indicate that economic and environmental tradeoffs can be effectively reflected through the proposed DSPMP model. The generated decision variables can help the decision makers justify and/or adjust their waste management strategies based on their implicit knowledge and preferences.

Experimental Research on the Expansibility Factor Calculation Model of V-Cone Flowmeters

This article aims to improve the accuracy of gas flow measurement of cone flowmeter and get a high-precision expansibility factor calculation model with wide applicable pressure range and different upstream side pressure. The experimental research was based on the DN50 and DN100 two sets of V-Cone flowmeter designed by Tianjin University. As the standard gas flow facility by means of critical flow venturi nozzles was insufficient supply capacity and poor pressure stability in positive pressure method, the experimental data obtained from standard gas flow facility by using negative pressure method was used to fit out the V-Cone flowmeter expansibility factor calculation model --TJU-2012 model. The model was tested with the experimental data obtained from the standard gas flow facility and compared with other four cone flowmeter expansibility factor calculation models, its maximum relative error was better than 0.9% and square averaged root error was better than 0.6%, both of them are the least.

A FLOW AND PRESSURE DISTRIBUTION OF APR+ REACTOR UNDER THE 4-PUMP RUNNING CONDITIONS WITH A BALANCED FLOW RATE

In order to quantify the flow distribution characteristics of APR+ reactor, a test was performed on a test facility, ACOP (APR+ Core Flow & Pressure Test Facility), having a length scale of 1/5 referring to the prototype plant. The major parameters are core inlet flow and outlet pressure distribution and sectional pressure drops along the major flow path inside reactor vessel. To preserve the flow characteristics of prototype plant, the test facility was designed based on a preservation of major flow path geometry. An Euler number is considered as primary dimensionless parameter, which is conserved with a 1/40.9 of Reynolds number scaling ratio. ACOP simplifies each fuel assembly into a hydraulic simulator having the same axial flow resistance and lateral cross flow characteristics. In order to supply boundary condition to estimate thermal margins of the reactor, the distribution of inlet core flow and core exit pressure were measured in each of 257 fuel assembly simulators. In total, 584 points of static pressure and differential pressures were measured with a limited number of differential pressure transmitters by developing a sequential operation system of valves. In the current study, reactor flow characteristics under the balanced fourcold leg flow conditions at each of the cold legs were quantified, which is a part of the test matrix composing the APR+ flow distribution test program. The final identification of the reactor flow distribution was obtained by ensemble averaging 15 independent test data. The details of the design of the test facility, experiment, and data analysis are included in the current paper.

Noise Radiation from a Continuous Mold-Line Link Flap Configuration

The results of an experimental study of the noise from a Continuous Mold-Line Link (CML) flap are presented. Acoustic and unsteady surface pressure measurements were performed on a main element wing section with a half-span CML flap in NASA Langley's Quiet Flow Facility. The acoustic data were acquired with a medium aperture directional array (MADA) of microphones. The Deconvolution Approach for the Mapping of Acoustic Sources (DAMAS) method is applied to determine the spatial distribution and strength of the noise sources over the surface of the test model. A Coherent Output Power (COP) method which relates the output from unsteady surface pressure sensors to the output of the MADA is also used to obtain more detailed characteristics of the noise source distribution in the trailing edge region of the CML. These results are compared to those obtained for a blunt flap to quantify the level of noise benefit that is achieved with the CML flap. The results indicate that the noise from the CML region of the flap is 5 to 17 dB lower (depending on flap deflection and Mach number) than the noise from the side edge region of the blunt flap. Lower noise levels are obtained for all frequencies. Spectral analysis of the noise from the cove region of the CML and blunt flap models also reveal a spectral peak in the high frequency range that is related to noise scattering at the trailing edge of the main element. The peaks in the CML and blunt flap cove noise spectra are close in level and often exceed blunt side edge noise. Applying a strip of serrated tape to the trailing edge of the CML flap model main airfoil reduced the peak but increased other noise somewhat. Directivity measurements show that the CML flap can be more directional than the blunt flap.

Seven-year surveillance of nosocomial invasive aspergillosis in a French University Hospital

This study aims at describing the evolution of the epidemiology of invasive aspergillosis (IA) in a French University Hospital focussing on nosocomial cases, in order to assess the efficiency of the environmental preventive measures which were implemented. From 2003 to 2009, IA cases were reviewed monthly and classified according to the EORTC/MSG criteria and the origin of contamination. Five proven and 65 probable IA cases were diagnosed. Most of the cases (74.3%) occurred in patients with haematological malignancies. Incidences of IA and nosocomial IA (NIA) were 0.106 and 0.032 cases per 1000 admissions, respectively. All the 21 NIA cases occurred in the absence of air treatment (laminar air flow facilities or Plasmair decontamination units) and/or during construction works. The 3-month and 1-year overall survival rates were 50.6% [38.2-61.7] and 31.1% [20-42.9] respectively, and did not differ according to the origin of contamination. Nosocomial IA still accounted for a third of all IA cases diagnosed from 2003 to 2009 and mainly occurred in the absence of environmental protective measures, which were confirmed to be effective when applied. Our results show that extension and/or reinforcement of these measures is needed, especially in the haematology unit and during construction works.

Design and realization of the high-precision weighing systems as the gravimetric references in PTB's national water flow standard

PTB's ‘Hydrodynamic Test Field’, which represents a high-accuracy water flow calibration facility, serves as the national primary standard for liquid flow measurands. As the core reference device of this flow facility, a gravimetric standard has been incorporated, which comprises three special-design weighing systems: 300 kg, 3 tons and 30 tons. These gravimetric references were realized as a combination of a strain-gauge-based and an electromagnetic-force-compensation load-cell-based balance, each. Special emphasis had to be placed upon the dynamics design of the whole weighing system, due to the high measurement resolution and the dynamic behavior of the weighing systems, which are dynamically affected by mechanical vibrations caused by environmental impacts, flow machinery operation, flow noise in the pipework and induced wave motions in the weigh tanks. Taking into account all the above boundary conditions, the design work for the gravimetric reference resulted in a concrete foundation ‘rock’ of some 300 tons that rests on a number of vibration isolators. In addition to these passively operating vibration isolators, the vibration damping effect is enhanced by applying an electronic level regulation device.

A flow facility for the characterization of pulsatile flows

In this paper a new flow facility for studies of pulsating flows is described. The pulsating flow is generated by means of a rotating valve and the flow is quantified through a newly developed flow measurement module accurately measuring the phase averaged flow distribution. The measuring probe of the module consists of a hot/cold-wire pair that enables both the mass flux and recovery temperature to be measured simultaneously. Calibrations of both the hot and cold wire are done in-situ in steady flow by means of a Pitot tube and a thermocouple. Moreover, the phase averaged flow distribution can be obtained by an automatic traverse of the measuring probe across the pipe cross section in both the radial and azimuthal directions. In the paper we exemplify and describe the flow properties, using the new flow measurement module, both in steady and pulsating flow.

Design-optimization of a broadband phased microphone array for aeroacoustic applications

Phased microphone arrays are commonly used in acoustic beamforming applications. While numerous beamforming algorithms have been proposed to alleviate deficiencies of the delay-and-sum approach, few studies have focused on the array design itself. In aeroacoustic applications, the most common designs are based on circularly symmetric spiral arrays devised by Underbrink (1995). The design of an array using such a method is complex and tedious due to the numerous design variables and corresponding trade-offs between resolution, sidelobe suppression, size, and cost. In this paper, a systematic design-optimization approach is described that offers several objective functions and constraints. Candidate arrays for use in the University of Florida Aeroacoustic Flow Facility (UFAFF) are designed for a broadband frequency range of 1 to 80 kHz. The results of these different cases will be compared to those of an existing array design currently used in the UFAFF. An optimized design is selected and fabricated for characterization and testing in the UFAFF. These results and comparison are described.

Computation of wall pressure fluctuations and flow induced noise by large eddy simulation

In industrial practice, the cavity-type oscillation is undesirable from the perspective of inducement of structure vibration and fatigue, generation of noise and drastic increase in drag on the body. A numerical work for the prediction of wall pressure fluctuations and flow-induced noise of cavity is performed in the paper. Firstly, the wall pressure fluctuations of a plate are computed and compared with experimental results of Small Anechoic Flow Facility in CSSRC. The robustness of large eddy simulation (LES) in unsteady flow calculation is analyzed. Secondly, the calculations of wall pressure fluctuations of shuttle holes are accomplished. The power spectra of wall pressure fluctuations are analyzed. The numerical predictions are compared with measured data. Finally, the flow induced noises of three cavities are predicted through LES and FW-H acoustic analogy. The computed results including flow pattern in cavity, vorticity distribution and radiated sound spectrum are analyzed. The computed results are compared with experimental data of Large Circulation Channel in CSSRC, and the numerical prediction method is validated. It shows that the numerical prediction method in the paper is credible. Key words: wall pressure fluctuations; flow induced noise; Large eddy simulation; FW-H acoustic analogy; cavity

The onset of roughness effects in the transitionally rough regime

Understanding the relationship between a surface’s topography and its hydraulic resistance is an important, yet elusive, goal in fluids engineering. Particularly poorly understood are the flow conditions at which a given surface will begin to show the effects of roughness in the form of increased wall shear stress above that of the hydraulically smooth wall. This phenomenon is the focus of the present study. The results from a small scale fully-developed turbulent channel flow facility are presented for a hydraulically smooth wall and three types of rough surfaces (a sandpaper surface, two ship bottom paints and painted surfaces smoothed by sanding). Experiments were conducted over a Reynolds number (ReH) range of 5800–64,000 based on the channel height and the bulk mean velocity. The onset of roughness effects occurs for the sandpaper surface at krms+∼1 or ks+∼5. This value of ks+ and the shape of the roughness function in the transitionally rough regime agree rather well with the results of Nikuradse (1933) for uniform sand. The frictional resistance of the two painted surfaces agree within experimental uncertainty despite a factor of two difference in krms. The onset of roughness effects occurs at a maximum peak to trough roughness height, kt+, of ∼10. Painted surfaces sanded with progressively finer sandpaper (60–220 grit) show roughness effects for krms+∼0.5–0.7 or kt+∼9, while the 400 grit sandpaper displays hydraulically smooth conditions over the entire Reynolds number range. The roughness scale that best predicts the onset of roughess effects is kt, indicating that the largest roughness features have the most influence in determining when a surface ceases to be hydraulically smooth. It is also of note that the roughness functions for the marine paint and painted-sanded surfaces do not exhibit either Nikuradse or Colebrook-type behavior.

Flow and noise predictions for the tandem cylinder aeroacoustic benchmark

Flow and noise predictions for the tandem cylinder benchmark are performed using lattice Boltzmann and Ffowcs Williams–Hawkings methods. The numerical results are compared to experimental measurements from the Basic Aerodynamic Research Tunnel and Quiet Flow Facility (QFF) at NASA Langley Research Center. The present study focuses on two configurations: the first configuration corresponds to the typical setup with uniform inflow and spanwise periodic boundary condition. To investigate installation effects, the second configuration matches the QFF setup and geometry, including the rectangular open jet nozzle, and the two vertical side plates mounted in the span to support the test models. For both simulations, the full span of 16 cylinder diameters is simulated, matching the experimental dimensions. Overall, good agreement is obtained with the experimental surface data, flow field, and radiated noise measurements. In particular, the presence of the side plates significantly reduces the excessive spanwise coherence observed with periodic boundary conditions and improves the predictions of the tonal peak amplitude in the far-field noise spectra. Inclusion of the contributions from the side plates in the calculation of the radiated noise shows an overall increase in the predicted spectra and directivity, leading to a better match with the experimental measurements. The measured increase is about 1 to 2 dB at the main shedding frequency and harmonics, and is likely caused by reflections on the spanwise side plates. The broadband levels are also slightly higher by about 2 to 3 dB, likely due to the shear layers from the nozzle exit impacting the side plates.

Shear layers in the turbulent pipe flow of drag reducing polymer solutions

A range of high molecular weight polymers (polyethylene oxide) was dissolved at very low concentrations – in the order of few wppm – in a solvent (water). The Newtonian character of the polymer solutions was confirmed by rheological measurements. The polymer solutions were then pumped through a long horizontal pipe section in fully developed turbulent conditions. The flow experienced a reduction in frictional drag when compared to the drag experienced by the equivalent flow of the pure solvent. Specifically, drag reduction was measured at Reynolds numbers ranging from 3.5×104 to 2.1×105 in a pressure driven flow facility with a circular tube section of internal diameter 25.3mm. The turbulent flow was visualized by Particle Image Velocimetry and the resulting data were used to investigate the effect of the drag reducing additives on the turbulent pipe flow. Close attention was paid to the mean and instantaneous velocity fields, as well as the two-dimensional vorticity and streamwise shear strain rate. The results indicate that drag reduction is accompanied by the appearance of “shear layers” (i.e. thin filament-like regions of high spatial velocity gradients) that act as interfaces separating low-momentum flow regions near the pipe wall and high-momentum flow regions closer to the centerline. The shear layers are not stationary. They are continuously formed close to the wall at a random frequency and move towards the pipe centerline until they eventually disappear, thus occupying or existing within a “shear layer region”. It is found that the mean thickness of the shear layer region is correlated with the measured level of drag reduction. The shear layer region thickness is increased by the presence of polymer additives when compared to the pure solvent, in a similar way to the thickening of the buffer layer. The results provide valuable insights into the characteristics of the turbulent pipe flow of a solvent containing drag reducing polymers that can be used to further our understanding of the role of polymers on the mechanism of drag reduction and to develop advanced drag reduction models.

Scaling between Wind Tunnels–Results Accuracy in Two-Dimensional Testing

The establishment of exact two-dimensional flow conditions in wind tunnels is a very difficult problem. This has been evident for wind tunnels of all types and scales. In this paper, the principal factors that influence the accuracy of two-dimensional wind tunnel test results are analyzed. The influences of the Reynolds number, Mach number and wall interference with reference to solid and flow blockage (blockage of wake) as well as the influence of side-wall boundary layer control are analyzed. Interesting results are brought to light regarding the Reynolds number effects of the test model versus the Reynolds number effects of the facility in subsonic and transonic flow.

Noise Radiation from a Continuous Mold-Line Link Flap Configuration

The results of an experimental study of the noise from a Continuous Mold-Line Link (CML) flap are presented. Acoustic and unsteady surface pressure measurements were performed on a main element wing section with a half-span CML flap in NASA Langley's Quiet Flow Facility. The acoustic data were acquired with a medium aperture directional array (MADA) of microphones. The Deconvolution Approach for the Mapping of Acoustic Sources (DAMAS) method is applied to determine the spatial distribution and strength of the noise sources over the surface of the test model. A Coherent Output Power (COP) method which relates the output from unsteady surface pressure sensors to the output of the MADA is also used to obtain more detailed characteristics of the noise source distribution in the trailing edge region of the CML. These results are compared to those obtained for a blunt flap to quantify the level of noise benefit that is achieved with the CML flap. The results indicate that the noise from the CML region of the flap is 5 to 17 dB lower (depending on flap deflection and Mach number) than the noise from the side edge region of the blunt flap. Lower noise levels are obtained for all frequencies. Spectral analysis of the noise from the cove region of the CML and blunt flap models also reveal a spectral peak in the high frequency range that is related to noise scattering at the trailing edge of the main element. The peaks in the CML and blunt flap cove noise spectra are close in level and often exceed blunt side edge noise. Applying a strip of serrated tape to the trailing edge of the CML flap model main airfoil reduced the peak but increased other noise somewhat. Directivity measurements show that the CML flap can be more directional than the blunt flap.

THE IPOS FRAMEWORK: LINKING FISH SWIMMING PERFORMANCE IN ALTERED FLOWS FROM LABORATORY EXPERIMENTS TO RIVERS

ABSTRACTThe current understanding of the effects of turbulence on the swimming performance of fish is primarily derived from laboratory experiments under pressurised flow swim tunnels and open‐channel flow facilities. These studies have produced valuable information on the swimming mechanics and behaviour of fish in turbulent flow. However, laboratory studies have limited representation of the flows fish experience in nature. The flow structure in rivers is imparted primarily by the highly heterogeneous nonuniform bed, and the flow is generally much more complex than in laboratory experiments. The goal of the current work is to direct future laboratory and field studies to adopt a common framework that will shape the integration of both approaches. This article outlines four characteristics of turbulent flow, which we suggest should be evaluated when generalising results from fish turbulent studies in both the laboratory and the field. The framework is based on four turbulence characteristics that are summarised under the acronym IPOS: intensity, periodicity, orientation and scale. Copyright © 2011 John Wiley & Sons, Ltd.

Novel water flow facility in france range extension to low flow rates (10 000 ml/h down to 1 ml/h)

In order to extend the French water flow calibration range, LNE-CETIAT is on progress to build a new reference for flow rate measurements ranging from 10 000 ml.h -1 down to 1 ml.h -1 . This new facility based on a gravimetric principle will enable calibration with water temperature between 10 °C and 50 °C. Flow is regulated by the combined use of a tightly regulated "upstream" pressure (0,1 to 10 bar) and the use of capillaries under laminar flow. The expected relative uncertainty for the water flow rate is 0.1 % with a coverage factor k = 2 (95% confidence). The paper described the design and the ongoing implementation of this new calibration facility.