scholarly journals Electro-mechanical model of indicator polymer fiber-optic PEL-coating for diagnosing mechanical effects.

2021 ◽  
Author(s):  
A.A. Pan’kov ◽  
Keyword(s):  
Optical Fiber ◽  
Light Flux ◽  
Mechanical Effect ◽  
Polymer Fiber ◽  
Mechanical Effects ◽  
Flux Intensity ◽  
Characteristic Points ◽  
Informative Characteristic ◽  
Indicator Coating ◽  
Static Pressing

A mathematical model of the functioning of the indicator polymer piezoelectroluminescent (PEL) coating for diagnosing external mechanical effects - quasi-static pressing of rigid ball particles has been developed. The algorithm of numerical processing of informative intensity of light flux at the output from optical fiber built into indicator coating of optical fiber PEL-sensor is presented. A numerical analysis for the case of single mechanical effect revealed the regularities of influence of the values of the sensor spiral pitch on the informative parts of the resulting spectra of light flux intensity and pressure distribution along the length of the sensor spiral. Informative characteristic points of pressure spectra plots were revealed; these are points of maxima, abscissa and values of which make it possible to find the desired values of radius and pressing force of a rigid ball particle.

scholarly journals XXXI.—On the Dynamical Theory of Heat. Part V. On the Quantities of Mechanical Energy contained in a Fluid in Different States, as to Temperature and Density

1853 ◽  
Vol 20 (3) ◽  
pp. 475-482 ◽  
Author(s):  
William Thomson
Keyword(s):  
Mechanical Energy ◽  
Dynamical Theory ◽  
Mechanical Effect ◽  
The Body ◽  
The Other ◽  
Final States ◽  
Mechanical Effects ◽  
Intermediate States

81. A body which is either emitting heat, or altering its dimensions against resisting forces, is doing work upon matter external to it. The mechanical effect of this work, in one case, is the excitation of thermal motions, and in the other, the overcoming of resistances. The body must itself be altering in its circumstances, so as to contain a less store of work within it, by an amount precisely equal to the aggregate value of the mechanical effects produced: and conversely, the aggregate value of the mechanical effects produced, must depend solely on the initial and final states of the body, and is therefore the same, whatever be the intermediate states through which the body passes, provided the initial and final states be the same.

scholarly journals Dynamic model of control of vibration damping mode by fiber optic PEL-sensor with phase shifting of control electric voltage.

2020 ◽  
Vol 2020 (10) ◽  
Author(s):  
A.A. Pan'kov ◽  
Keyword(s):  
Optical Fiber ◽  
Dynamic Model ◽  
Electrical Impedance ◽  
Coherent Control ◽  
Mechanical Energy ◽  
Light Flux ◽  
Electric Circuit ◽  
Phase Shifting ◽  
Frequency Range ◽  
Electric Voltage

A mathematical dynamic model of the operation of the vibration pressure optical fiber piezoelectroluminescent (PEL) sensor in the damping mode was developed taking into account the electrical conductivities and Maxwell-Wagnerian relaxation of electric fields in the phases for the case of harmonic stress (vibration pressure) on the external cylindrical surface of the sensor. Analytical solution of damping of stationary axisymmetric oscillations of optical fiber PEL-sensor is obtained and investigated by applying coherent control electric voltage to electrodes of sensor with phase shifting relative to vibration pressure. Regularities of frequency dependencies for real, imaginary parts of control, informative transfer and damping coefficients of sensor are established and studied. Analysis of influence of value and shift angle of phases of control electric voltage on results of numerical simulation for intensity of light flux at output from optical fiber of sensor under action of vibration pressure is performed. Frequency dependencies were found for the electrical impedance of the AC electric circuit of the sensor in comparison with the approximation of these dependencies by electromechanical analogy. It was revealed that in the frequency range under consideration, the electrical impedance of the sensor with satisfactory accuracy is based on consideration of an equivalent electric circuit with parallel connection of frequency-dependent active and capacitive elements. Frequency range and values of control parameters are set for effective active damping of vibration pressure through conversion to Joule heat (dissipation) of mechanical energy supplied to the sensor. The results of comparing the analytical and numerical (in the ANSYS package) approaches confirm the validity and adequacy of the decisions obtained.

scholarly journals A numerical toolkit to understand the mechanics of partially saturated granular materials

2015 ◽  
Vol 770 ◽  
pp. 1-4 ◽  
Author(s):  
J.-N. Roux
Keyword(s):  
Granular Material ◽  
Phenomenological Models ◽  
Granular Materials ◽  
Lattice Boltzmann ◽  
Discrete Element ◽  
Mechanical Effect ◽  
Saturation Level ◽  
Partially Saturated ◽  
Mechanical Effects ◽  
Granular Assemblies

The mechanisms by which a wetting, non-saturating liquid bestows macroscopic cohesion and strength to a granular material are usually not accessible to micromechanical investigations for saturations exceeding the pendular regime of isolated menisci, easily studied by discrete element models (DEM). The paper by Delenne et al. (J. Fluid Mech., 2015, vol. 762, R5) exploiting a multiphase lattice Boltzmann approach, pioneers the simulation of the micromorphology and of the mechanical effects on grains of an interstitial liquid, in equilibrium with its vapour, for the whole saturation range. Interestingly, in accordance with some experiments and phenomenological models, the results suggest that the mechanical effect of capillary forces is maximized for some intermediate saturation level (near 40 % in the model), well beyond the pendular range. In general, the proposed simulation technique opens the way to many studies of partially saturated granular assemblies, for different saturation or imbibition processes and histories.

scholarly journals Dynamics of growth parameters of Gentiana lutea L. in vitro plants under different lighting conditions

2021 ◽  
Vol 28 ◽  
pp. 58-65
Author(s):  
L. R. Hrytsak ◽  
M. Z. Prokopiak ◽  
O. Yu. Mayorova ◽  
Kh. M. Kolisnyk ◽  
N. M. Drobyk
Keyword(s):  
Growth Parameters ◽  
Spectral Composition ◽  
Light Flux ◽  
In Vitro Plants ◽  
Gentiana Lutea ◽  
Plant Cultivation ◽  
In Situ Conditions ◽  
Flux Intensity ◽  
Cultivation In Vitro

Aim. Study of the dynamics Gentiana lutea L. plant growth processes in vitro depending on the light regime changes of their cultivation in order to develop a scheme to increase their adaptive potential. Methods. Methods of plant cultivation in vitro, biometric method, as well as ANOVA variance analysis and middle group analysis in pairs using the Tukey test (Tukey test) were used. Results. It is shown that the cultivation of G. lutea plants in vitro using 25 W/m2 light flux intensity in the region of photosynthetically active radiation and the ratio of blue (Eb): green (Eg): red (Er) ranges = 41.8%: 42.7 %: 15.5% triggers non-specific photomorphogenesis reactions for intact plants, which lead to poor root system development, stem elongation, formation of small leaves with a thin leaf blade, overall low productivity and low adaptation potential of G. lutea plants to ex vitro and in situ conditions. Increasing the light flux intensity to 44 W/m2 and increasing the red wave proportion up to 20.3% allows not only to improve the bioproductivity of G. lutea plants which are cultivated in vitro, but also to increase the coefficient of microclonal reproduction without the additional use of exogenous growth regulators. The greatest growth of the aboveground and underground parts, increase in effective leaf surface are observed in vitro plants during cultivation at 135 W/m2 light flux intensity and spectral composition Eb: Eg: Er = 29.5%: 32.5%: 38.0%. Conclusions. It is possible to improve plant bioproductivity by changing the light conditions of plant cultivation in vitro, and, accordingly, to increase the adaptive potential to ex vitro and in situ conditions. Keywords: Gentiana lutea L., in vitro plants, light flux intensity, spectral composition, growth parameters.

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