• Structural Engineering and Mechanics
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• v.6 no.7
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• pp.747-756
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• 1998

In this paper the influence of rotary inertia, shear and compressibility on the value of the critical force for the Beck's column is analyzed. The constitutive equation is of Engesser's type. As a result, the critical load parameter for which instability of flutter type occurs is calculated for several values of the column's parameters.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.7-13
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• 2012

Ultrasonic velocities (u) for binary mixtures of propylene carbonate (PC) (1) with benzene and substituted benzenes (2) viz. benzene, ethylbenzene, o-xylene and p-xylene have been measured at 288.15-308.15 K over the entire range of composition. The experimental values of ultrasonic velocities (u) have been utilized to calculate isentropic compressibility ($K_s$), intermolecular free length ($L_f$), acoustic impedance (Z).

• International Journal of Aeronautical and Space Sciences
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• v.13 no.2
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• pp.188-198
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• 2012

An improvement to the k-${\varepsilon}$ turbulence model is presented and is shown to lead to better agreement with data regarding supersonic base flows. The improvement was achieved by imposing a grid-independent realizability constraint in the Launder-Sharma k-${\varepsilon}$ model. The effects of compressibility were also examined. The numerical results show that the modified Launder-Sharma model leads to some improvement in the prediction of the velocity and turbulent kinetic energy profiles. Compressibility corrections also lead to better agreement in both the turbulent kinetic energy and the Reynolds stress profiles with the experimental data.

• Journal of Powder Materials
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• v.12 no.4 s.51
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• pp.296-302
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• 2005

In order to improve mechanical properties, the hypereutectic Al-20 wt%Si based prealloy powder was prepared by gas atomization process. Microstructure and compressibility of the atomized Al-Si powder were investigated. The average powder size was decreased with increasing the atomization gas pressure. Size of primary Si particles of the as-atomized powder was about $5-8\;\mu{m}$. The as-atomized Al-Si powder such as AMB 2712 and AMB 7775 to increase compressibility and sinterability. Relative density of the mixed powder samples sintered at $600^{\circ}C$ was reached about 96% of a theoretical density.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.2
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• pp.123-129
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• 1998

Compressibility and permeability properties are the most important input parameters necessary to assess the suitability of core materials in seepage control system construction. To achieve this objective, an experimental investigation was conducted in the laboratory. For the bentonite-soil/sand mixes, consolidation and permeability tests were carried out in the conventional consolidation cell, 6Omm in diameter and 2Omm in height, was modified to perform a falling head type permeability test. From the results, the normalized relationship with respect to void ratio at liquid-limit state $(e_L)$, and the changes of compressibility and permeability for various bentonite-soil/sand mixes were presented. This approach will be helpful in proportioning mixes and predicting corresponding changes in engineering behavior. And it is possible to proportion a mix to arrive at the required compressibility without affecting the permeability.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.3
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• pp.67-73
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• 2004

Effect of calendering on structural and surface properties of sheets made of various pulp was investigated. BKP, BCTMP and KOCC were used as raw materials for handsheets and sheets were calendered at the different calendering temperature and pressure conditions. Caliper, air permeability, and PPS roughness were reduced by calendering, but their effects were a little different depending on pulp type and calendering condition. Increase of density with increase of calendering Pressure was remarkable on sheet made of BCTMP or KOCC, and the effect of temperature was more significant than pressure. PPS roughness of sheet made of BCTMP or KOCC was reduced by calendering, but BKP sheet showed little reduction of roughness at higher calendering pressure. The compressibility of sheet increased logarithmetically with calendering pressure and surface compressibility of KOCC sheet was relatively higher than other pulps.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1013-1022
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• 2005

Because depth of deposit is deeper as well as compressibility is very larger than the other regions in Korea, behaviour of settlement at Nak-Dong river estuarine causes hot issue at ground improvement. Defined properties for design differ from measurement. Therefore it affects cost of construction. This study presents design standard to engineers as it defined properties of compressibility at Jangyu Area of Nak-Dong river estuarine. To search value of representation for region, back analysis was performed using the measurement. To verify that, the measurement of recently designed site was confirmed, and the cost of construction with properties of consolidation was calculated.

• Structural Engineering and Mechanics
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• v.13 no.4
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• pp.355-368
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• 2002

In this paper, we address the numerical investigation on the effect of liquid compressibility onto the natural frequency of liquid-filled containers. Traditionally the liquid motion has been treated as an ideal fluid motion. However, from the numerical experiments for the axisymmetrical free-vibration of cylindrical liquid-storage tanks, we found that the relative difference in natural frequencies between ideal and compressible motions becomes remarkable, as the slenderness of tank or the relative liquid-fill height becomes larger. Therefore, in such cases of dynamic systems, the liquid compressibility becomes an important parameter, for the accurate vibration analysis. For the free-vibration analysis of compressible liquid-structure interaction we employed the coupled finite element formulation expressed in terms of the acoustic wave pressure and the structure deformation.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.4
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• pp.387-397
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• 2013

An assessment of two-equation turbulence models, the low Reynolds k-${\varepsilon}$ and k-${\omega}$ SST models, with the compressibility corrections proposed by Sarkar and Wilcox, has been performed. The compressibility models are evaluated by investigating transonic or supersonic flows, including the arc-bump, transonic diffuser, supersonic jet impingement, and unsteady supersonic diffuser. A unified implicit finite volume scheme, consisting of mass, momentum, and energy conservation equations, is used, and the results are compared with experimental data. The model accuracy is found to depend strongly on the flow separation behavior. An MPI (Message Passing Interface) parallel computing scheme is implemented.

• Geomechanics and Engineering
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• v.1 no.2
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• pp.169-178
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• 2009

Due to the enormous amount of fills required, broken rock-fine grain soil mixtures have been increasingly used in the construction of high-fill foundations for airports, railways and highways in the mountain areas of western China. However, the compressibility behavior of those broken rock-fine grain soil mixtures remains unknown, which impose great uncertainties for the performance of those high-fill foundations. In this research, the mixture of broken limestone and a fine grain soil, Douposi soil, is studied. Large oedometer tests have been performed on specimens with different soil content. This research reveals the significant influence of fine grains on the compressibility of the mixture, including immediate settlement, creep, as well as wetting deformation.