On the possibility of coherent Doppler determination of the aerosol-size spectrum in a turbulent flow

1978 ◽  
Vol 21 (11) ◽  
pp. 1184-1186
Author(s):  
G. N. Glazov ◽  
S. I. Tuzova
Keyword(s):  
Turbulent Flow ◽  
Size Spectrum

A Continuous Size Spectrum for Particulate Matter in the Sea

1967 ◽  
Vol 24 (5) ◽  
pp. 909-915 ◽  
Author(s):  
R. W. Sheldon ◽  
T. R. Parsons
Keyword(s):  
Particle Diameter ◽  
Particulate Material ◽  
Size Spectrum ◽  
Particulate Carbon ◽  
Particle Volume ◽  
Carbon And Nitrogen ◽  
Total Particle ◽  
Volume Measurements ◽  
Good Agreement

The size spectrum of particulate material in seawater can easily be expressed as total particle volume versus the logarithm of particle diameter. This appears to be the most informative way to present the data and it is also aptly suited to the classical divisions of nanno-, micro-, and macroplankton.A realistic measure of the volume of irregularly shaped particles such as phytoplankton chains could be made with a Coulter Counter. Particle volume measurements were in good agreement with estimates based on microscopic determination of particle diameter. There were also highly significant correlations between total particle volume, as indicated by the counter, and particulate carbon and nitrogen.

The Reynolds Stress in Channel Flows From a Lagrangian Treatment of the Turbulence Momentum

2019 ◽  
Author(s):  
T.-W. Lee
Keyword(s):  
Turbulent Flow ◽  
Reynolds Stress ◽  
Current Approach ◽  
Navier Stokes ◽  
Current Transport ◽  
Lagrangian Analysis ◽  
Navier Stokes Equation ◽  
Mechanistic Approach ◽  
Turbulent Momentum

Abstract We have developed a mechanistic approach for determination of the Reynolds stress, using a Lagrangian analysis of turbulent momentum. Analysis and comparison with DNS and experimental data point toward the soundness of this approach (Lee, 2018). von Karman constant, the inner layer thickness and the Reynolds stress itself are all recovered through this approach, in agreement with DNS data. In addition, the turbulent flow profiles can be calculated iteratively using the basic Reynolds-averaged Navier-Stokes equation, in conjunction with the current transport equation for the Reynolds stress. In this work, we explore these and further uses of the current approach in solving turbulent flow dynamics.

The determination of transverse pulsations of turbulent flow velocity in fast-axial flow CO2 laser by phase-conjugation method

2005 ◽  
Author(s):  
S. A. Buyarov ◽  
M. G. Galuskin ◽  
V. D. Dubrov ◽  
V. Y. Panchenko ◽  
Yu. N. Zavalov
Keyword(s):  
Turbulent Flow ◽  
Flow Velocity ◽  
Phase Conjugation ◽  
Axial Flow ◽  
Conjugation Method

II. Determination of constitutive coefficients and illustrative examples

1989 ◽  
Vol 327 (1595) ◽  
pp. 449-475 ◽  
Keyword(s):  
Turbulent Flow ◽  
Constitutive Equations ◽  
Theoretical Calculations ◽  
Equations Of Motion ◽  
Plane Channel ◽  
General System ◽  
Turbulent Fluctuation ◽  
System Of Equations ◽  
Constitutive Response

This paper is a continuation of Part I under the same title and is concerned mainly with the determination of the constitutive response coefficients, as well as some simple illustrative examples. First, a system of simplified constitutive equations for incompressible viscous turbulent flow is obtained from the more general system of equations in Part I through a judicial choice of retaining only those terms which appear to represent major features of the turbulent flow. Even for this simplified system of equations, the identification of some of the constitutive coefficients presents a formidable task; and this is especially true in the case of those coefficients that are associated with the presence of the additional independent variables of the theory due to the manifestation of the alignment of eddies (on the microscopic scale), turbulent fluctuation and eddy density. Because of this difficulty, the present effort for identification of the various constitutive coefficients must be regarded partly as tentative, pending future availability of suitable relevant experimental data and/or pertinent numerical simulation results. Keeping this background in mind, most of the relevant coefficients in the constitutive equations are determined, or the nature of their functional forms are estimated, through consideration of‘cartoon-like’ models on the microscopic level and these results are then used in conjunction with the macroscopic equations of motion to examine a number of simple solutions. These include the possibility of a flow possessing a constant uniform velocity gradient and solutions pertaining to decay of flow anisotropy and plane turbulent channel flows. The predicted theoretical calculations are in general accord with experimental observations. In addition, for plane channel flow, plots of variation along the width of the channel for the turbulent temperature and the macroscopic velocity compare favourably with corresponding known experimental results.

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