The Experts below are selected from a list of 825 Experts worldwide ranked by ideXlab platform

Sean C C Bailey - One of the best experts on this subject based on the ideXlab platform.

  • estimating the value of von karman s constant in turbulent pipe flow
    Journal of Fluid Mechanics, 2014
    Co-Authors: Sean C C Bailey, Marcus Hultmark, Margit Vallikivi, Alexander Smits
    Abstract:

    Five separate data sets on the mean velocity distributions in the Princeton University/ONR Superpipe are used to establish the best estimate for the value of von Karman’s constant for the flow in a fully developed, hydraulically smooth pipe. The profiles were taken using Pitot Tubes, conventional hot wires and nanoscale thermal anemometry probes. The value of the constant was found to vary significantly due to measurement uncertainties in the mean velocity, friction velocity and the wall distance, and the number of data points included in the analysis. The best estimate for the von Karman constant in turbulent pipe flow is found to be $0.40 \pm 0.02$ . A more precise estimate will require improved instrumentation.

  • obtaining accurate mean velocity measurements in high reynolds number turbulent boundary layers using Pitot Tubes
    Journal of Fluid Mechanics, 2013
    Co-Authors: Sean C C Bailey, Marcus Hultmark, J P Monty, P H Alfredsson, M S Chong, Richard D Duncan, Jens H M Fransson, N Hutchins, Ivan Marusic, Beverley Mckeon
    Abstract:

    This article reports on one component of a larger study on measurement of the zero-pressure-gradient turbulent flat plate boundary layer, in which a detailed investigation was conducted of the suite of corrections required for mean velocity measurements performed using Pitot Tubes. In particular, the corrections for velocity shear across the tube and for blockage effects which occur when the tube is in close proximity to the wall were investigated using measurements from Pitot Tubes of five different diameters, in two different facilities, and at five different Reynolds numbers ranging from Re_θ = 11 100 to 67 000. Only small differences were found amongst commonly used corrections for velocity shear, but improvements were found for existing near-wall proximity corrections. Corrections for the nonlinear averaging of the velocity fluctuations were also investigated, and the results compared to hot-wire data taken as part of the same measurement campaign. The streamwise turbulence-intensity correction was found to be of comparable magnitude to that of the shear correction, and found to bring the hot-wire and Pitot results into closer agreement when applied to the data, along with the other corrections discussed and refined here.

Beverley Mckeon - One of the best experts on this subject based on the ideXlab platform.

  • obtaining accurate mean velocity measurements in high reynolds number turbulent boundary layers using Pitot Tubes
    Journal of Fluid Mechanics, 2013
    Co-Authors: Sean C C Bailey, Marcus Hultmark, J P Monty, P H Alfredsson, M S Chong, Richard D Duncan, Jens H M Fransson, N Hutchins, Ivan Marusic, Beverley Mckeon
    Abstract:

    This article reports on one component of a larger study on measurement of the zero-pressure-gradient turbulent flat plate boundary layer, in which a detailed investigation was conducted of the suite of corrections required for mean velocity measurements performed using Pitot Tubes. In particular, the corrections for velocity shear across the tube and for blockage effects which occur when the tube is in close proximity to the wall were investigated using measurements from Pitot Tubes of five different diameters, in two different facilities, and at five different Reynolds numbers ranging from Re_θ = 11 100 to 67 000. Only small differences were found amongst commonly used corrections for velocity shear, but improvements were found for existing near-wall proximity corrections. Corrections for the nonlinear averaging of the velocity fluctuations were also investigated, and the results compared to hot-wire data taken as part of the same measurement campaign. The streamwise turbulence-intensity correction was found to be of comparable magnitude to that of the shear correction, and found to bring the hot-wire and Pitot results into closer agreement when applied to the data, along with the other corrections discussed and refined here.

Marcus Hultmark - One of the best experts on this subject based on the ideXlab platform.

  • estimating the value of von karman s constant in turbulent pipe flow
    Journal of Fluid Mechanics, 2014
    Co-Authors: Sean C C Bailey, Marcus Hultmark, Margit Vallikivi, Alexander Smits
    Abstract:

    Five separate data sets on the mean velocity distributions in the Princeton University/ONR Superpipe are used to establish the best estimate for the value of von Karman’s constant for the flow in a fully developed, hydraulically smooth pipe. The profiles were taken using Pitot Tubes, conventional hot wires and nanoscale thermal anemometry probes. The value of the constant was found to vary significantly due to measurement uncertainties in the mean velocity, friction velocity and the wall distance, and the number of data points included in the analysis. The best estimate for the von Karman constant in turbulent pipe flow is found to be $0.40 \pm 0.02$ . A more precise estimate will require improved instrumentation.

  • obtaining accurate mean velocity measurements in high reynolds number turbulent boundary layers using Pitot Tubes
    Journal of Fluid Mechanics, 2013
    Co-Authors: Sean C C Bailey, Marcus Hultmark, J P Monty, P H Alfredsson, M S Chong, Richard D Duncan, Jens H M Fransson, N Hutchins, Ivan Marusic, Beverley Mckeon
    Abstract:

    This article reports on one component of a larger study on measurement of the zero-pressure-gradient turbulent flat plate boundary layer, in which a detailed investigation was conducted of the suite of corrections required for mean velocity measurements performed using Pitot Tubes. In particular, the corrections for velocity shear across the tube and for blockage effects which occur when the tube is in close proximity to the wall were investigated using measurements from Pitot Tubes of five different diameters, in two different facilities, and at five different Reynolds numbers ranging from Re_θ = 11 100 to 67 000. Only small differences were found amongst commonly used corrections for velocity shear, but improvements were found for existing near-wall proximity corrections. Corrections for the nonlinear averaging of the velocity fluctuations were also investigated, and the results compared to hot-wire data taken as part of the same measurement campaign. The streamwise turbulence-intensity correction was found to be of comparable magnitude to that of the shear correction, and found to bring the hot-wire and Pitot results into closer agreement when applied to the data, along with the other corrections discussed and refined here.

Tao Wang - One of the best experts on this subject based on the ideXlab platform.

  • flow measurement of wet co2 using an averaging Pitot tube and coriolis mass flowmeters
    International Journal of Greenhouse Gas Control, 2017
    Co-Authors: Kehinde Adefila, Tao Wang
    Abstract:

    The flow measurement of wet-gas is an active field with extensive research background that remains a modern-day challenge. The implication of wet-gas flow conditions is no different in Carbon Capture and Storage (CCS) pipelines. The associated complex flow regime with wet-gas flow makes it difficult to accurately meter the flow rate of the gas phase. Some conventional single-phase flowmeters like the Coriolis, Orifice plate, Ultrasonic, V-Cone, Venturi and Vortex have been tested for this application, usually accompanied with special recommendations. Often, a correlation equation valid within a certain range of specific conditions is required to correct the response of the flowmeter. This paper presents investigations into the suitability and performance of one of the most advanced averaging Pitot Tubes for the flow measurement of wet CO2 gas. The averaging Pitot tube with flow conditioning wing geometry (APT-FCW) was studied and experimentally assessed in earlier work for the flow measurement of pure and dry CO2 within an error of ±1%. Under wet-gas conditions, however, the APT-FCW sensor is found to give an error of up to ±25% and within ±1.5% after appropriate correcting solutions are applied for a liquid fraction of up to 20%.

  • flow measurement of gaseous co 2 using averaging Pitot Tubes
    Instrumentation and Measurement Technology Conference, 2014
    Co-Authors: Kehinde Adefila, Yong Yan, Lijun Sun, Tao Wang
    Abstract:

    In this paper, an Averaging Pitot Tube (APT) with Flow Conditioning Wing (FCW) geometry is used as a practical sensing device to measure and characterize the flow of single-phase gaseous CO 2 . The technique demonstrates a simple, cost-effective and potentially accurate option towards the measurement, accurate accounting and characterization of CO 2 in Carbon Capture and Storage pipelines. The metrological performance of the flow sensor is verified using air medium before being applied for gaseous CO 2 . With a Coriolis mass flow meter acting as a secondary calibration reference to further validate the performance of the APT-FCW flow sensor, both metering instruments were evaluated against a weighing scale apparatus. From experimental and calibration data with air, the APT-FCW's average K-factor and linearity error are found to be 0.5091 and 0.725%, respectively. With operating conditions remaining unaltered in this particular flow measurement application and a target accuracy of ±1%, the error achieved for the Coriolis meter is better than ±0.5% and ±1% for the APT-FCW. Test results and other performance evaluation of the instruments are also discussed.

George R Inger - One of the best experts on this subject based on the ideXlab platform.

  • Viscous Effects on Cooled Pitot Tubes in Hypersonic Low Reynolds Number Flows
    AIP Conference Proceedings, 2005
    Co-Authors: George R Inger
    Abstract:

    The influence of low Reynolds Number viscous effects on blunt nose stagnation pressure is investigated analytically for near‐continuum hypersonic ideal gas flows around cooled bodies. It is shown that normal stress within the boundary layer acts to slightly increase stagnation pressure but that the usually‐neglected pressure slip at the wall introduces a significant opposing effect when the wall is cooled. Closed form relationships describing this behavior as a function of Reynolds number, wall temperature ratio and gas type are developed and shown to agree with experiment.

  • Viscous Effects on Cooled Pitot Tubes in Hypersonic Low Reynolds Number Flows
    Journal of Thermophysics and Heat Transfer, 2004
    Co-Authors: George R Inger
    Abstract:

    The influence of low Reynolds number viscous effects on blunt-nose stagnation pressure is investigated analytically for near-continuum hypersonic ideal gas flows around cooled bodies. It is shown that normal stress within the boundary layer acts to increase stagnation pressure slightly but that the usually neglected pressure slip at the wall introduces a significant opposing effect when the wall is cooled. Closed-form relationships describing this behavior as a function of Reynolds number, wall temperature ratio, and gas type are developed