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1

Influence of viscosity on the shape of an air Taylor bubble in a stagnant liquid under turbulent condition in falling film

Lertnuwat B.

International Journal of Applied Mechanics and Engineering

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2019

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Vol. 24, no. 1

67--77

EN

This work aims to find the influence of the liquid viscosity on the shape of an air Taylor bubble, rising up in a pipe column which contains the liquid under conditions that the liquid is stagnant and the Froude number is approximately equal to 0.35. Five liquid viscosities (from 0.001 to 0.01 Pa · s) were selected for being computationally investigated. An appropriate shape of a Taylor bubble, corresponding to each selected viscosity, was obtained by considering a pressure distribution of the air inside the bubble. Simulation results showed that the Taylor bubble shape would be thicker if the liquid viscosity was decreased. This could be explained by using the theory of the log-law velocity profile.

2

Inelastic stability analysis of uniaxially compressed flat rectangular isotropic CCSS plate

Ibearugbulem O. M., Eziefula U. G., Onwuka D. O.

International Journal of Applied Mechanics and Engineering

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2015

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Vol. 20, no. 3

637--645

EN

This study investigates the inelastic stability of a thin flat rectangular isotropic plate subjected to uniform uniaxial compressive loads using Taylor-Maclaurin series formulated deflection function. The plate has clamped and simply supported edges in both characteristic directions (CCSS boundary conditions). The governing equation is derived using a deformation plasticity theory and a work principle. Values of the plate buckling coefficient are calculated for aspect ratios from 0.1 to 2.0 at intervals of 0.1. The results compared favourably with the elastic stability values and the percentage differences ranged from -0.353% to -7.427%. Therefore, the theoretical approach proposed in this study is recommended for the inelastic stability analysis of thin flat rectangular isotropic plates under uniform in-plane compression.

3

Improving the stability of discretization zeros with the Taylor method using a generalization of the fractional-order hold

Zeng C., Liang S., Zhang Y., Zhong J., Su Y.

International Journal of Applied Mathematics and Computer Science

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2014

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Vol. 24, no. 4

745--757

EN

Remarkable improvements in the stability properties of discrete system zeros may be achieved by using a new design of the fractional-order hold (FROH) circuit. This paper first analyzes asymptotic behaviors of the limiting zeros, as the sampling period T tends to zero, of the sampled-data models on the basis of the normal form representation for continuous-time systems with a new hold proposed. Further, we also give the approximate expression of limiting zeros of the resulting sampled-data system as power series with respect to a sampling period up to the third order term when the relative degree of the continuous-time system is equal to three, and the corresponding stability of the discretization zeros is discussed for fast sampling rates. Of particular interest are the stability conditions of sampling zeros in the case of a new FROH even though the relative degree of a continuous-time system is greater than two, whereas the conventional FROH fails to do so. An insightful interpretation of the obtained sampled-data model can be made in terms of minimal intersample ripple by design, where multirate sampled systems have a poor intersample behavior. Our results provide a more accurate approximation for asymptotic zeros, and certain known results on asymptotic behavior of limiting zeros are shown to be particular cases of the ideas presented here.

4

An analytical globar-local Taylor transformation-based vibration solution for annular FGM sandwich plates supported by nonuniform elastic foundations

Alipour M. M., Shariyat M.

Archives of Civil and Mechanical Engineering

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2014

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Vol. 14, no. 1

6--24

EN

Free vibration of functionally graded annular sandwich plates resting on Winkler-type elastic foundations is investigated based on a zigzag global–local plate theory and a finite Taylor's transform whose center is located at the outer edge. Material properties of each layer may be graded in the transverse direction according to a power law. It is the first time that a global–local theory is combined with a layerwise analytical solution for analysis of the annular functionally graded sandwich plates. Various edge conditions are considered for the inner and outer edges. A parametric study including evaluating effects of the material properties distributions of the core and face sheets, symmetric and asymmetric layups, thickness to radius ratio of the plate, inner to outer radius ratio, coefficient of the elastic foundation, and the edge conditions on vibration behavior of the annular plate is carried out. Accuracy of the employed sandwich plate theory and the presented analytical solution are verified by comparing present results with those of the three-dimensional theory of elasticity extracted from ABAQUS software.

5

Współrzędnościowa technika pomiarowa w badaniach dynamicznych właściwości materiałów metodą Taylora

Grązka M., Janiszewski J.

Mechanik

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2011

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R. 84, nr 1

56-56

PL

Przedstawiono metodę pomiaru niezdeformowanej części walca odkształconego plastycznie podczas testu Taylora. Zastosowanie opracowanej strategii pomiaru oraz współrzędnościowej maszyny pomiarowej umożliwiło zredukowanie czasu pomiarowego o ok. 300% w stosunku do pomiarów metodami konwencjonalnymi.

EN

The method for measurement of the undeformed part of cylindrical specimen strained dynamically under Taylor impact test conditions was presented in this paper. By applying developed measuring procedure and by using coordinate measuring machine, measurement time of specimen was reduced about 300% in relation to conventional measurement method.