Publications
227 results found
Taylor AMKP, Yianneskis M, 1982, Developing flow in S-shaped ducts. 1: square cross-section duct.
Laser-Doppler velocimetry was used to measure the laminar and turbulent flow in an S-duct formed with two 22.5 deg sectors of a bend with ratio of mean radius of curvature to hydraulic diameter of 7.0. The wall pressure distribution was also measured for the turbulent flow and quantifies the expected large variations which occur at different radial locations. (from authors' abstract)
Anderson BH, Taylor AMKP, Whitelaw JH, et al., 1982, Developing flow in S-shaped ducts.
The secondary flows in a square section S duct were measured at five stations within the duct for Reynolds numbers of 790 and 40,000 in a water tunnel. Laser Doppler velocimetry was used to measure velocities in the plane of curvature and, in turbulent flow, to measure the associated fluctuations and cross correlations. For turbulent flow, wall pressure distributions are also reported. An important objective of this work is to provide observations in sufficient detail and accuracy for the evaluation of numerical calculation methods. Accordingly, the measurements are available in tabular form and on magnetic tape for ease of reference. (from authors' abstract)
Taylor AMKP, Whitelaw JH, Yianneskis M, 1982, Curved ducts with strong secondary motion: velocity measurements of developing laminar and turbulent flow., Journal of Fluids Engineering, Transactions of the ASME, Vol: 104, ISSN: 0098-2202
The paper describes the investigation of hydrodynamically developing flow at the entrance to a square cross sectioned 90 DEGREE bend of 2.3 radius ratio for laminar and turbulent flows. The purposes of the measurements are to provide a basis for the understanding of the influence of developing entry flow in the bends under laminar and turbulent regimes; and to provide detailed observations, particularly of the secondary motion velocities in a form suitable for the evaluation of numerical solution techniques. (from paper)
Enayet MM, Gibson MM, Taylor AMKP, et al., 1982, LASER DOPPLER MEASUREMENTS OF LAMINAR AND TURBULENT FLOW IN A PIPE BEND.
Measurements were made of the streamwise components of velocity in the flow through a ninety-degree bend of circular cross section for which the ratio of the radius of curvature to the diameter is 2. 8. The results show the development of strong pressure-driven secondary flow in the form of a pair of counter-rotating vortices in the streamwise direction. Refractive index matching at the fluid-wall interface has not been employed; the displacement of the measurement volume due to refraction is allowed for in simple geometrical calculations.
Taylor AMKP, Whitelaw JH, Yianneskis M, 1982, Measurements in ducted flows by laser Doppler anemometry.
An important purpose of the present contribution is to indicate advantages of water flow and laser Doppler anemometry for the purpose of obtaining information about ducted flows. Thus, the previous results of experiments carried out by the authors are discussed and some examples presented. In addition, new measurements are reported that were obtained in a transition duct with a square cross section at inlet and a round cross section at outlet. (from paper)
Taylor AMKP, Yianneskis M, 1982, Developing flow in S-shaped ducts. 1: square cross-section duct.
Laser-Doppler velocimetry was used to measure the laminar and turbulent flow in an S-duct formed with two 22.5 deg sectors of a bend with ratio of mean radius of curvature to hydraulic diameter of 7.0. The wall pressure distribution was also measured for the turbulent flow and quantifies the expected large variations which occur at different radial locations. (from authors' abstract)
Enayet MM, Gibson MM, Taylor AMKP, et al., 1982, Laser-Doppler measurements of laminar and turbulent flow in a pipe bend, International Journal of Heat and Fluid Flow, Vol: 3, Pages: 213-219, ISSN: 0142-727X
Laser-Doppler measurements are reported for laminar and turbulent flow through a 90° bend of circular cross-section with mean radius of curvature equal to 2.8 times the diameter. The measurements were made in cross-stream planes 0.58 diameters upstream of the bend inlet plane, in 30, 60 and 75° planes in the bend and in planes one and six diameters downstream of the exit plane. Three sets of data were obtained: for laminar flow at Reynolds numbers of 500 and 1093 and for turbulent flow at the maximum obtainable Reynolds number of 43 000. The results show the development of strong pressure-driven secondary flows in the form of a pair of counter-rotating vortices in the streamwise direction. The strength and character of the secondary flows were found to depend on the thickness and nature of the inlet boundary layers, inlet conditions which could not be varied independently of Reynolds number. The quantitative anemometer measurements are supported by flow visualization studies. Refractive index matching at the fluid-wall interface was not used; the measurements consist, therefore, of streamwise components of mean and fluctuating velocities only, supplemented by wall pressure measurements for the turbulent flow. The displacement of the laser measurement volume due to refraction is allowed for in simple geometrical calculations. The results are intenden for use as benchmark data for calibrating flow calculation methods. © 1982.
Taylor AMKP, Whitelaw JH, Yianneskis M, 1982, MEASUREMENTS IN DUCTED FLOWS BY LASER DOPPLER ANEMOMETRY., Pages: 589-599
TAYLOR A, WHITELAW JH, YIANNESKIS M, 1982, CURVED DUCTS WITH STRONG SECONDARY MOTION - VELOCITY-MEASUREMENTS OF DEVELOPING LAMINAR AND TURBULENT-FLOW, JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME, Vol: 104, Pages: 350-359, ISSN: 0098-2202
- Author Web Link
- Cite
- Citations: 50
Taylor AMKP, Whitelaw JH, Yianneskis M, 1981, TURBULENT FLOW IN A SQUARE-TO-ROUND TRANSITION., NASA Contractor Reports, ISSN: 0565-7059
Measurements of turbulent flow in a duct with a cross-sectional transition from square to round are presented. Laser Doppler velocimetry was used to measure the mean velocity components, turbulence levels and shear stresses. The boundary layers at the inlet and exit of the transition were approximately 13 and 20% of the hydraulic diameter, respectively, becoming thicker near the corner fillets. The results show the development of secondary flow, or magnitudes up to 7% of the bulk velocity. This flow is directed away from the corner fillets and along the periphery of the duct and is associated with the longitudinal curvature of the wall and the related pressure gradients.
Taylor AMKP, Whitelaw JH, Yianneskis M, 1981, TURBULENT FLOW IN A SQUARE-TO-ROUND TRANSITION., NASA Contractor Reports, ISSN: 0565-7059
Measurements of turbulent flow in a duct with a cross-sectional transition from square to round are presented. Laser Doppler velocimetry was used to measure the mean velocity components, turbulence levels and shear stresses. The boundary layers at the inlet and exit of the transition were approximately 13 and 20% of the hydraulic diameter, respectively, becoming thicker near the corner fillets. The results show the development of secondary flow, or magnitudes up to 7% of the bulk velocity. This flow is directed away from the corner fillets and along the periphery of the duct and is associated with the longitudinal curvature of the wall and the related pressure gradients.
Taylor AMKP, Whitelaw JH, Yianneskis M, 1981, Measurements of laminar and turbulent flow in a curved duct with thin inlet boundary layers. Final report.
Laser Doppler velocimetry was used to measure the laminar and turbulent flow in a 90 deg square bend of strong curvature. The boundary layers at the inlet to the bend were approximately 25 percent and 15 percent of the hydraulic diameter of the laminar and turbulent flows, respectively. The development of the pressure driven secondary motion is more rapid for laminar flow: the maximum cross stream component measured was 60 percent of the bulk velocity in contrast to 40 percent for turbulent flow. The streamwise isotachs show that, for laminar flow, large velocities are found progressively nearer to the outer radius of the bend and along the sidewalls. For turbulent flow, the isotachs move towards the inner radius until about 60 deg around the bend where strong secondary motion results in a similar redistribution. Turbulence level and shear stress measurements are also presented. (A)
Taylor AMKP, Whitelaw JH, Yianneskis M, 1981, MEASUREMENTS OF LAMINAR AND TURBULENT FLOW IN A CURVED DUCT WITH THIN INLET BOUNDARY LAYERS., NASA Contractor Reports, ISSN: 0565-7059
Laser-Doppler velocimetry was used to measure the laminar and turbulent flow in a 90 degree square bend of strong curvature. The boundary layers at the inlet to the bend were approximately 25% and 15% of the hydraulic diameter for the laminar and turbulent flows, respectively. The development of the pressure-driven secondary motion is more rapid for laminar flow: the maximum cross-stream component measured was 60% of the bulk velocity, in contrast to 40% for turbulent flow. The streamwise isotachs show that, for laminar flow, large velocities are progressively nearer to the outer radius of the bend and along the sidewalls. For turbulent flow, the isotachs move toward the inner radius until about 60 degree around the bend, where strong secondary motion results in a similar redistribution. Turbulence level and shear stress measurements are also presented.
Taylor AMKP, Whitelaw JH, Yianneskis M, 1981, MEASUREMENTS OF LAMINAR AND TURBULENT FLOW IN A CURVED DUCT WITH THIN INLET BOUNDARY LAYERS., NASA Contractor Reports, ISSN: 0565-7059
Laser-Doppler velocimetry was used to measure the laminar and turbulent flow in a 90 degree square bend of strong curvature. The boundary layers at the inlet to the bend were approximately 25% and 15% of the hydraulic diameter for the laminar and turbulent flows, respectively. The development of the pressure-driven secondary motion is more rapid for laminar flow: the maximum cross-stream component measured was 60% of the bulk velocity, in contrast to 40% for turbulent flow. The streamwise isotachs show that, for laminar flow, large velocities are progressively nearer to the outer radius of the bend and along the sidewalls. For turbulent flow, the isotachs move toward the inner radius until about 60 degree around the bend, where strong secondary motion results in a similar redistribution. Turbulence level and shear stress measurements are also presented.
Taylor AMKP, Whitelaw JH, 1978, EFFECTIVENESS OF LEADING-EDGE COOLING ARRANGEMENTS., International Heat Transfer Conference, 6th
Measurements of the film-cooling effectiveness around the circumference of a cylinder are presented as a function of velocity ratio and hole arrangements. The geometrical configuration and flow properties simulate (apart from the Mach number) the flow around the leading edge of a nozzle guide vane or gas-turbine blade. Results, based on mass transfer measurements, were obtained for one, two and three rows of holes; the holes were angled at 30 degrees to the cylinder axis and along the span. The effect of the circumferential location of the rows of holes with respect to the stagnation line is also quantified. In general, the results show that the effectiveness increases with velocity ratio and number of rows of holes and that, with the present pitch to diameter ratio of 3. 2, the three-dimensional nature of the geometry is reflected by the downstream measurements. 7 refs.
Taylor AMKP, Whitelaw JH, 1978, EFFECTIVENESS OF LEADING-EDGE COOLING ARRANGEMENTS.
Measurements of the film-cooling effectiveness around the circumference of a cylinder are presented as a function of velocity ratio and hole arrangements. The geometrical configuration and flow properties simulate (apart from the Mach number) the flow around the leading edge of a nozzle guide vane or gas-turbine blade. Results, based on mass transfer measurements, were obtained for one, two and three rows of holes; the holes were angled at 30 degrees to the cylinder axis and along the span. The effect of the circumferential location of the rows of holes with respect to the stagnation line is also quantified. In general, the results show that the effectiveness increases with velocity ratio and number of rows of holes and that, with the present pitch to diameter ratio of 3. 2, the three-dimensional nature of the geometry is reflected by the downstream measurements. 7 refs.
Humphrey JAC, Taylor AMK, Whitelaw JH, 1977, Laminar flow in a square duct of strong curvature, Journal of Fluid Mechanics, Vol: 83, Pages: 509-527, ISSN: 0022-1120
Calculated values of the three velocity components and measured values of the longitudinal component are reported for the flow of water in a 90° bend of 40 x 40mm cross-section; the bend had a mean radius of 92mm and was located downstream of a 1.8m and upstream of a 1.2m straight section. The experiments were carried out at a Reynolds number, based on the hydraulic diameter and bulk velocity, of 790 (corresponding to a Dean number of 368). Flow visualization was used to identify qualitatively the characteristics of the flow and laser-Doppler anemometry to quantify the velocity field. The results confirm and quantify that the location of maximum velocity moves from the centre of the duct towards the outer wall and, in the 90° plane, is located around 85% of the duct width from the inner wall. Secondary velocities up to 65% of the bulk longitudinal velocity were calculated and small regions of recirculation, close to the outer corners of the duct and in the upstream region, were also observed. The calculated results were obtained by solving the Navier–Stokes equations in cylindrical co-ordinates. They are shown to exhibit the same trends as the experiments and to be in reasonable quantitative agreement even though the number of node points used to discretize the flow for the finite-difference solution of the differential equations was limited by available computer time and storage. The region of recirculation observed experimentally is confirmed by the calculations. The magnitude of the various terms in the equations is examined to determine the extent to which the details of the flow can be represented by reduced forms of the Navier–Stokes equations. The implications of the use of so-called “partially parabolic” equations and of potential- and rotational-flow analysis of an ideal fluid are quantified. © 1977, Cambridge University Press. All rights reserved.
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.