Author: Carol Joan Russo
Publisher:
ISBN:
Category :
Languages : en
Pages : 304
Book Description
An Experimental Study of Grid Turbulence in a Liquid
Author: Carol Joan Russo
Publisher:
ISBN:
Category :
Languages : en
Pages : 304
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 304
Book Description
An Experimental Study of Grid Turbulence in Dilute High-polymer Solutions
Author: Andrew G. Fabula
Publisher:
ISBN:
Category : Polymerization
Languages : en
Pages : 596
Book Description
Longitudinal, one-dimensional turbulence spectra were measured behind a towed grid in dilute aqueous high-polymer solutions. Several types of hot-film flowmeters with constant-temperature bridges were used, with emphasis on quartz-coated, platinum-film sensors of conical shape. Measurements in water were consistent with wind-tunnel measurements. Cylindrical sensors were found unsuitable. The additives were poly(ethylene oxides), polyacrylamides, and guar gum. Concentrations of up to 137 ppm were used. The guar gum produced temporary suspensions which were not suitable for turbulence measurements because of high noise level. With the other additives, the sensor signal near the grid included a high-frequency component (called raggedness) which was attributed to temporary (or temporarily altered) inhomogeneity caused by the grid bars. Three types of spectral effects were the distortion due to raggedness, a greater experimental scatter near the grid in newly prepared solutions, and the predictable shift due to viscosity increase. (Author).
Publisher:
ISBN:
Category : Polymerization
Languages : en
Pages : 596
Book Description
Longitudinal, one-dimensional turbulence spectra were measured behind a towed grid in dilute aqueous high-polymer solutions. Several types of hot-film flowmeters with constant-temperature bridges were used, with emphasis on quartz-coated, platinum-film sensors of conical shape. Measurements in water were consistent with wind-tunnel measurements. Cylindrical sensors were found unsuitable. The additives were poly(ethylene oxides), polyacrylamides, and guar gum. Concentrations of up to 137 ppm were used. The guar gum produced temporary suspensions which were not suitable for turbulence measurements because of high noise level. With the other additives, the sensor signal near the grid included a high-frequency component (called raggedness) which was attributed to temporary (or temporarily altered) inhomogeneity caused by the grid bars. Three types of spectral effects were the distortion due to raggedness, a greater experimental scatter near the grid in newly prepared solutions, and the predictable shift due to viscosity increase. (Author).
An Experimental Study of Gasdynamical Turbulence
Author: Shih-chun Lin
Publisher:
ISBN:
Category : Gas dynamics
Languages : en
Pages : 474
Book Description
Publisher:
ISBN:
Category : Gas dynamics
Languages : en
Pages : 474
Book Description
AN EXPERIMENTAL STUDY OF GRID TURBULENCE IN A THERMALLY-STRATIFIED FLOW..
Author: RICHARD DOUGLAS MONTGOMERY
Publisher:
ISBN:
Category :
Languages : en
Pages : 169
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 169
Book Description
An Experimental Study of the Response of a Nearly Isotropic Grid Turbulence to a Spectrally Local Disturbance
Author: Eric C. Itsweire
Publisher:
ISBN:
Category : Laminar flow
Languages : en
Pages : 494
Book Description
Publisher:
ISBN:
Category : Laminar flow
Languages : en
Pages : 494
Book Description
Experimental Study of Turbulence Generation and Control by Fractal Grids
Author: S. M. M. Salim
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Turbulence generation and control have been an immense interest among scientists and researchers due to the fact that nearly all industrial flows are turbulent. In some cases, turbulence is highly desired, for example chemical plants need higher turbulence for the efficient mixing of various substances whereas, in oil and pipe industries, whereas, turbulence in the pipe flows causes higher energy input to sustain the flow along the pipe length. Thus, control of turbulence directly contributes to cutting costs. The existing approaches to control such flows are case specific and no single universal approach exists owing to the lack of understanding of underlying physics. Many approaches have been taken to generate turbulence in laboratory set-ups for the past hundred years to study turbulence control. One such approach is the use of a rectangular grid through which the fluid is forced to generate so called grid turbulence. In contrast, we have made use of fractal geometry to generate turbulence for similar study. The self-similar edge characteristic of the fractal grids is thought to play the vital role in the enhanced mixing properties. Four sets of fractal grids, each with equal flow area, were used in the study. Our results from the experiments conducted in a circular wind tunnel indicate that it is possible to significantly improve the generation and control of turbulence by the introduced fractal approach.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Turbulence generation and control have been an immense interest among scientists and researchers due to the fact that nearly all industrial flows are turbulent. In some cases, turbulence is highly desired, for example chemical plants need higher turbulence for the efficient mixing of various substances whereas, in oil and pipe industries, whereas, turbulence in the pipe flows causes higher energy input to sustain the flow along the pipe length. Thus, control of turbulence directly contributes to cutting costs. The existing approaches to control such flows are case specific and no single universal approach exists owing to the lack of understanding of underlying physics. Many approaches have been taken to generate turbulence in laboratory set-ups for the past hundred years to study turbulence control. One such approach is the use of a rectangular grid through which the fluid is forced to generate so called grid turbulence. In contrast, we have made use of fractal geometry to generate turbulence for similar study. The self-similar edge characteristic of the fractal grids is thought to play the vital role in the enhanced mixing properties. Four sets of fractal grids, each with equal flow area, were used in the study. Our results from the experiments conducted in a circular wind tunnel indicate that it is possible to significantly improve the generation and control of turbulence by the introduced fractal approach.
Experimental Study of Turbulent Flow Generated by a Pulsating Grid
Author: Sean D. M. O'Connell
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 236
Book Description
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 236
Book Description
Springer Handbook of Experimental Fluid Mechanics
Author: Cameron Tropea
Publisher: Springer Science & Business Media
ISBN: 3540251413
Category : Science
Languages : en
Pages : 1570
Book Description
Accompanying DVD-ROM contains ... "all chapters of the Springer Handbook."--Page 3 of cover.
Publisher: Springer Science & Business Media
ISBN: 3540251413
Category : Science
Languages : en
Pages : 1570
Book Description
Accompanying DVD-ROM contains ... "all chapters of the Springer Handbook."--Page 3 of cover.
Experimental Studies on the Turbulent Flow Behind Grids
Author: I. C. T. Nisbet
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 306
Book Description
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 306
Book Description
Quantum Turbulence
Author: Shu-Chen Liu
Publisher: LAP Lambert Academic Publishing
ISBN: 9783838315386
Category :
Languages : en
Pages : 156
Book Description
QUANTUM TURBULENCE : DECAY OF GRID TURBULENCE IN A DISSIPATIONLESS FLUID We produced grid turbulence in liquid helium at 520 mK to compare with classical experiments and theories. Above T = 1 K, with viscosity present, it has been shown that grid turbulence is equivalent to homogeneous isotropic turbulence in a classical fluid. We seek to investigate the nature of grid turbulence when viscosity is zero. Specifically, in the absence of viscosity in a quantum fluid, through what path does the turbulence decay? To produce grid turbulence, a magnetically shielded superconducting linear motor was designed and built to accelerate and decelerate the grid rapidly in a short distance (~ 1 mm), and achieve glide speeds up to 1 m/s, when driven with the properly shaped current pulse. We measured the decay of the turbulence produced by calorimetry technique. Recent theory suggests the decay occurs through a Kelvin-wave cascade on the vortex lines which couples the initially large turbulent eddies to the short wavelength phonon spectrum of the liquid, yielding a characteristic rate of temperature rise. Initial measurements support the Kelvin wave cascade theory.
Publisher: LAP Lambert Academic Publishing
ISBN: 9783838315386
Category :
Languages : en
Pages : 156
Book Description
QUANTUM TURBULENCE : DECAY OF GRID TURBULENCE IN A DISSIPATIONLESS FLUID We produced grid turbulence in liquid helium at 520 mK to compare with classical experiments and theories. Above T = 1 K, with viscosity present, it has been shown that grid turbulence is equivalent to homogeneous isotropic turbulence in a classical fluid. We seek to investigate the nature of grid turbulence when viscosity is zero. Specifically, in the absence of viscosity in a quantum fluid, through what path does the turbulence decay? To produce grid turbulence, a magnetically shielded superconducting linear motor was designed and built to accelerate and decelerate the grid rapidly in a short distance (~ 1 mm), and achieve glide speeds up to 1 m/s, when driven with the properly shaped current pulse. We measured the decay of the turbulence produced by calorimetry technique. Recent theory suggests the decay occurs through a Kelvin-wave cascade on the vortex lines which couples the initially large turbulent eddies to the short wavelength phonon spectrum of the liquid, yielding a characteristic rate of temperature rise. Initial measurements support the Kelvin wave cascade theory.