Download or read book Velocity Measurements in Dilute Polymer Solutions written by Carl Alan Friehe and published by . This book was released on 1968 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pressure Fluctuation Measurements in Dilute Polymer Solutions written by D. N. Contractor and published by . This book was released on 1967 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of the fluctuating total head in the wake of a flat plate are described with ejection of a dilute polymer solution near the leading edge of the plate. A turbulence probe, consisting of a total-head tube with piezoelectric crystal gage, was specially designed, fabricated and calibrated for this purpose. Turbulence intensities and spectral density distributions were calculated from the measurements, which were made across the wake at a fixed distance downstream of the trailing edge of the plate. The results indicated that the non-dimensionalized profiles of local mean velocity and turbulence intensities in the wake with polymer ejection, are similar to those without any ejection. The shapes of the local spectral density distributions of the turbulent energy over the range of frequencies tested (25-500 cps), are also similar with and without polymer ejection. The total turbulent energy in the wake decreases when polymer solution is ejected and the reduction in total turbulent energy varies with polymer concentration similarly to the reduction in drag on the flat plate. (Author).
Download or read book Pipe Flow of Dilute Polymer Solutions written by Chien-Bang Wang and published by . This book was released on 1969 with total page 810 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Influence of Polymer Additives on Velocity and Temperature Fields written by Bernhard Gampert and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Symposium on "The Influence of Polymer Additives on Veloc ity and Temperature Fields" was proposed to the General Assem bly of the International Union of Theoretical and Applied Me chanics (IUTAM) by the "Gesellschaft fur Angewandte Mathematik und Mechanik" (GAMM). The Symposium was held under the auspices of IUTAM in association with the "Deutsche Rheologische Ge sellschaft" (DRG) with responsibility for the organization ly ing with B. Gampert (Universitat-GH-Essen). The main aim of this IUTAM Symposium was to consider the funda mental aspects of the phenomena that occur when small amounts of polymers are added to turbulent flows (turbulent drag re duction) and laminar porous media flows. In particular atten tion was devoted to - the influence of molecular parameters of the polymers and solution properties, especially the elongational viscosity, on turbulent flow and laminar porous media flow; the influence of polymers on the turbulence structure in polymer drag reduction
Download or read book Elongational Viscosity Measurements of Dilute Polymer Solutions written by Jeffrey Colt and published by . This book was released on 1980 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow of Dilute Polymer Solutions about Circular Cylinders written by Turgut Sarpkaya and published by . This book was released on 1971 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flow of aqueous solutions of Polyox WSR-301, with concentrations of 1.0 to 200 wppm, past circular cylinders was investigated in the drag-transition region of Reynolds numbers. Drag force, pressure distribution, and separation angle were measured on cylinders with diameters from 1/4 to 1-1/2 inch. Lift and drag forces acting on a NACA-0024 hydrofoil-model were also measured. The polymer additive was found to alter only those force coefficients which have a Reynolds-number transition region. Two distinct types of cylinder drag transition were observed: (1) At high concentrations, transition from sub-critical to a transcritical flow occurred at the same free-stream velocity independent of body diameter; and (2) at low concentrations and/or molecular weights, tripping from a sub-critical to a super-critical flow occurred at a well defined flow condition which was a function of free-stream velocity, body diameter, and turbulent pipe-flow friction reduction. In all cases, transition occurred earlier than that in the pure solvent. The polymer had a de-stabilizing effect on the boundary-layer flow.
Download or read book Non Newtonian Flow of Dilute Polymer Solutions written by Gerhard de Wind and published by . This book was released on 1951 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Fluid Mechanics Measurements written by MOHAMED GAD-EL-HAK and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 611 pages. Available in PDF, EPUB and Kindle. Book excerpt: One cannot overemphasize the importance of studying fluids in motion or at rest for a variety of scientific and engineering endeavors. Fluid mechanics as an art reaches back into antiquity, but its rational formulation is a relatively recent undertaking. Much of the physics of a particular flow situation can be understood by conducting appropriate experiments. Flow visualization techniques offer a useful tool to establish an overall picture of a flow field and to delineate broadly its salient features before embarking on more detailed quantitative measurements. Among the single-point measurements that are particularly difficult are those in separated flows, non-Newtonian fluids, rotating flows, and nuclear aerosols. Pressure, shear stress, vorticity, and heat transfer coefficient are also difficult quantities to measure, particularly for time-dependent flows. These and other special situations are among the topics covered in this volume. Each article emphasizes the development of a particular measuring technique. The topics covered were chosen because of their importance to the field, recent appeal, and potential for future development. The articles are comprehensive and coverage is pedagogical with a bias towards recent developments.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1974 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulence Measurements with a Laser Doppler Velocimeter written by William Joseph Yanta and published by . This book was released on 1973 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulence measurements with a Laser Doppler Velocimeter (LDV) using the dual scatter or differential Doppler mode have been made in a subsonic, fully developed channel flow. The measurements were made using only those light scattering particles occurring naturally in air. Results include mean velocity profiles, turbulence intensities, Reynolds stress distributions and a skewness measurement of the velocity distribution function across the channel. Statistical techniques were used to obtain the various turbulence parameters. Guidelines have been established for the amount of data needed to obtain results with a specified accuracy and confidence level. Measurements have also been made to determine the particle-size distribution. An aerodynamic means was used to determine the size distribution, in contrast to the usual optical procedures. (Modified author abstract).
Download or read book Studies in Rheology and Hydrodynamics of Dilute Polymer Solutions written by Michael Poreh and published by . This book was released on 1969 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Five studies are presented in this publication: A comparison between the behaviour of polymer solutions and flow characteristics of linear elastico-viscous fluid models. The study shows that no linear model can predict consistently all the observed non-Newtonian phenomena of polymer solutions; Turbulent flow of dilute polymer solutions through an annulus. Experimental and theoretical results are presented; Measurements of the dynamic response of flowing polymer solutions with a vibrating torsional quartz crystal are presented. The dynamic elastico-viscous response is found to be independent of the flow characteristics and shear rates; Drag reduction in developing boundary layers by injection of polymer solutions. Reduction of local friction coefficients is of the order of 65 percent, however, energy losses in the injection region decrease the total drag reduction efficiency. Effect of the injection concentration and discharge, width of slot and mean stream velocity are found; Drag reduction and degradation tests of several polymer solutions are presented. (Author).
Download or read book Cavitation Dynamics and Flow Fields in Dilute Polymer Solutions written by Robert Yen-ying Ting and published by . This book was released on 1971 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1987 with total page 952 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure of Turbulence and Drag Reduction written by Albert Gyr and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 617 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1976 a similar titled IUTAM Symposium (Structure of Turbulence and Drag Reduction) was held in Washington . However, the progress made during the last thirteen years as weil as the much promising current research desired a second one this year. In Washington drag reduction by additives and by direct manipulation of the walls (compliant walls and heated surfaces) were discussed. In the meantime it became evident that drag reduction also occurs when turbulence is influenced by geometrical means, e.g. by influencing the pressure distribution by the shape of the body (airfoils) or by the introduction of streamwise perturbances on a body (riblets). In the recent years turbulence research has seen increasing attention being focused on the investigation of coherent structures, mainly in Newtonian fluids. We all know that these structures are a significant feature of turbulent flows, playing an important role in the energy balance in such flows. However their place in turbulence theories as weil as the factors influencing their development are still poorly understood. Consequently, the investigation of phenomena in which the properties of coherent structures are alte red provides a promising means of improving our understanding of turbulent flows in general.
Download or read book Drag Reduction and Shear Degradation of Dilute Polymer Solutions as Measured by a Rotating Disk written by T. T. Huang and published by . This book was released on 1972 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A saturated drag-reduction line for dilute polymer solutions is derived for a rotating disk from new velocity-similarity laws. Drag reduction measured by a rotating disk is found to have three domains--oversaturated, optimal and undersaturated. At a given boundary-layer thickness and wall-shear stress, the drag-reduction increases with increasing concentration in the undersaturated domain, and the drag reduction does not increase with increasing concentration in the oversaturated domain. The boundary between the two domains is the optimal drag reduction, which is determined by the type of polymer and its concentration and a Reynolds number based on shear velocity and disk radius or boundary-layer thickness. (Author).
Download or read book Report written by United States. National Bureau of Standards and published by . This book was released on 1968 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Scientific and Technical Reports and Publications for 1969 A Selected Listing written by United States. National Aeronautics and Space Administration. Scientific and Technical Information Division and published by . This book was released on 1970 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt:
