scholarly journals Validation of Dimensionless Parameters for Distinguishing between Homogeneous and Bubbling Fluidizations

2021 ◽  
Vol 11 (02) ◽  
pp. 81-97
Author(s):  
Kenya Kuwagi ◽  
Atsuto Kogane ◽  
Yui Sasaki ◽  
Hiroyuki Hirano
Author(s):  
J. F. Cass ◽  
S. J. Hogan

AbstractThe widely cited Haken–Kelso–Bunz (HKB) model of motor coordination is used in an enormous range of applications. In this paper, we show analytically that the weakly damped, weakly coupled HKB model of two oscillators depends on only two dimensionless parameters; the ratio of the linear damping coefficient and the linear coupling coefficient and the ratio of the combined nonlinear damping coefficients and the combined nonlinear coupling coefficients. We illustrate our results with a mechanical analogue. We use our analytic results to predict behaviours in arbitrary parameter regimes and show how this led us to explain and extend recent numerical continuation results of the full HKB model. The key finding is that the HKB model contains a significant amount of behaviour in biologically relevant parameter regimes not yet observed in experiments or numerical simulations. This observation has implications for the development of virtual partner interaction and the human dynamic clamp, and potentially for the HKB model itself.


2003 ◽  
Vol 129 (10) ◽  
pp. 777-782 ◽  
Author(s):  
Victor M. Ponce ◽  
Ahmad Taher-shamsi ◽  
Ampar V. Shetty

Author(s):  
Shuang-Shuang Zhou ◽  
M. Ijaz Khan ◽  
Sumaira Qayyum ◽  
B. C. Prasannakumara ◽  
R. Naveen Kumar ◽  
...  

This investigation aims to present the thermally developed bioconvection flow of Williamson nanoliquid over an inclined stretching cylinder in presence of linear mixed convection and nonuniform heat source/sink. The activation energy and suspension of gyrotactic microorganisms are accounted with applications of bioconvection phenomenon. Appropriate nondimensional variables are opted to attain the dimensionless form of flow equations. The resulting momentum, energy, concentration and motile density equations are abridged to highly coupled and nonlinear in nature. The numerical treatment is followed for the solution procedure by employing the shooting method. The influence of some relevant dimensionless parameters is discoursed graphically along with physical justifications. Moreover, the impact of several dimensionless parameters on skin friction and Nusselt number is obtained and listed in tables. It is observed that the velocity of fluid shows a decreasing variation for Williamson fluid parameter. The change in unsteadiness parameter and heat source parameter enhanced the nanofluid temperature. The motile microorganisms profile declines with bioconvection constant and bio-convection Lewis number.


2021 ◽  
pp. 1-14
Author(s):  
Ihor Vrublevskyi

Abstract Vibratory conveying of a material point by harmonic longitudinal and polyharmonic normal vibrations of an inclined conveying surface is considered. The dependence of dimensionless conveying velocity – a ratio of velocity to the product of frequency and amplitude of longitudinal vibration – on several dimensionless parameters is investigated in the moving modes without hopping. Maximal conveying velocity is achieved at the certain values of normal vibration amplitudes and phase difference angle between the longitudinal and normal vibrations, which are called optimal. Their values are dependent on two dimensionless parameters: the inclination angle parameter – a ratio of an inclination angle tangent to a frictional coefficient, the intensive vibration coefficient – a ratio of the longitudinal amplitude of vibration to the amplitude of the first harmonic of normal vibration and frictional coefficient. In a condition of the intensive longitudinal vibration, when its amplitude significantly greater than amplitudes of normal vibration, dimensionless velocity is almost independent of the intensive vibration parameter and it depends only on inclination angle parameter, i.e. on inclination angle and frictional coefficient. The optimal values of harmonics' amplitudes of polyharmonic normal vibration are determined in dependence of inclination angle parameter with the number of harmonics from 2 to 7. The graphs of considered dependencies are presented and the most important values of parameters are presented in the table. Conclusions are made to determine the optimal vibration parameters and the problems of further research are indicated. The considered vibrations can be used in different vibratory conveying devices with electromagnetic drives.


2001 ◽  
Author(s):  
Francine Battaglia ◽  
Ronald G. Rehm ◽  
Howard R. Baum ◽  
Mohamed I. Hassan ◽  
Kozo Saito

Abstract Perhaps the most dramatic example of surprising behavior when circulation is imposed on a combustion-driven flow is the fire whirl, where the burning gases form a tall slender column. Relatively few studies have addressed the influence of circulation on the development of combustion-driven flows. Three dimensionless parameters characterize this interplay: the Froude number, the swirl number and the Reynolds number. It is surprising that for most studies, even with plausible assumptions concerning the experiments, not enough information is given to determine the values of these parameters. We will experimentally reconstruct these studies in an effort to characterize parametrically these interactions. Both buoyancy-driven and momentum-driven combustion processes will be investigated to determine the influence of circulation. Theoretical studies will occur in conjunction to provide the most complete parametric investigation.


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