vol.27 (2013)

Bulletin of Research Center for Computing and Multimedia Studies
Vol.27, 2013 ISSN 1882-7694

Phase Equilibrium Calculations by Equation of State v2
Yosuke Kataoka, Yuri Yamada
Received: August 31, 2012    PDF    Abstract
Practical methods for phase equilibrium calculations by the equation of state for a perfect solid and liquid (v2) are described using examples of worksheets. Using the Microsoft Excel worksheets, the pressure, Gibbs energy and other thermodynamic quantities of a molecular system are obtained as functions of temperature and volume. Some examples of VBA (Visual Basic for Applications) programs are given to obtain volume and other thermodynamic properties as a function of temperature under a given pressure. The thermodynamic consistency test is performed as a function of temperature at a given pressure, where the difference between the heat capacity under a constant pressure and that under a constant volume should equal to an expression consisting of the thermal expansion coefficient, temperature, volume and isothermal compressibility.
Numerical Calculations in Phase Equilibrium by Equation of State v3
Yosuke Kataoka, Yuri Yamada
Received: September 10, 2012    PDF    Abstract
A practical method for phase equilibrium calculations using the equation of state for a perfect solid and a perfect liquid is shown along with examples of Excel worksheets. The molecular systems of a perfect solid and a perfect liquid are assumed to be composed of single -type spherical molecules. The molecular interaction is expressed by a Lennard -Jones potential function. The pressure and internal energy of the system are expressed as functions of temperature and volume. Other thermodynamic functions such as entropy are also given as functions of temperature and volume. A thermodynamic constancy test is performed.
Perfect Solid and Liquid
Yosuke Kataoka, Yuri Yamada
Received: December 23, 2012    PDF    Abstract
A 3-phase equilibrium in argon is obtained by the thermodynamics of the perfect solid and liquid. The equation of state (EOS) for a perfect solid is obtained for a pure substance of spherical molecules that undergo molecular interaction of the Lennard -Jones form. The primitive internal energy EOS for a perfect solid (referred to as v0 EOS) is the sum of the thermally averaged kinetic energy and the potential energy of the nearest neighbors in a face -centered cubic (FCC) solid at 0 K. The extended internal energy EOS for a perfect solid (v1) includes a long -range effect in the low density region as the internal energy in the van der Waals EOS. The pressure EOS is written as the volume derivative of the potential energy at 0 K to satisfy the EOS with respect to thermodynamics. The temperature effect in the virial term is included in the extended pressure EOS. The EOS for a perfect liquid is the van der Waals EOS with empirical coefficients to explain the 3-phase equilibrium. The change in entropy for a reversible process is calculated by the standard method. The thermodynamic quantities of each phase are written as functions of volume and temperature. In this way, the Gibbs energy per molecule is plotted as a function of pressure for both solid and liquid phases, and the crossing point in the plot is the phase transition point. The p-V-T relations on the equilibrium lines are comparable with the experimental and molecular simulation results. The calculated average potential energy and entropy on the phase boundaries are consistent with the simulations. The thermodynamic quantities under a low pressure are compared with the molecular dynamic simulations. The quantities examined are volume, internal energy, enthalpy, entropy, Helmholtz energy, Gibbs energy, expansion coefficient, isothermal compressibility and heat capacity under a constant pressure.
Development of the Transformer for Contactless Power Suppliers
Tatsuya Ohashi, Iliana Marinova, Yoshifuru Saito
Received: February 14, 2013    PDF    Abstract
Contactless power supplier is composed of a transformer having the distinct primary and secondary coils separated by air gap. Because of the electromagnetic compatibility problem, it is essential to keep the leakage magnetic fields around the contactless power supplier as low as possible. This paper carries out the wavelets multi -resolution analysis to the magnetic field distributions around contact- less power supplier. As a result, we have succeeded in obtaining one of the reasonable core shapes by observing the wavelets spectra of measured magnetic field vector distributions. Furthermore, it is revealed that a tested trial transformer gives nearly 80 percent power transmission efficiency even though the primary and secondary coils are separated by 10mm air gap.
Dynamic Analysis for Discrete Particle Model By Distinct Element Method -A Study on Advanced Direct Shear Test Simulation-
Takahiro Seguro, Tomohiro Itadani, Nagayuki Yoshida
Received: March 7, 2013    PDF    Abstract
The purpose of this paper is to simulate the advanced direct shear test by using Distinct Element Method (DEM). The advanced direct shear test is the shearing test suggested by Hajime Matsuoka. Compared with the ordinary direct shear test, when assuming the equal scale simulation this test allows to decrease the number of the particles required. During the analysis, it is confirmed that the shear stress curve declines drastically according to the stick -slip phenomenon. And it is also confirmed that the shear stress and the dilatancy curve vary as the initial position of the particles changes. This indicates that some contrivances are needed to prevent those irregularities. For this, the averaging is suggestedin this paper. As a result, the advanced direct shear test is correctly simulated by using DEM. Furthermore, the characteristics of the 2-dimensional DEM simulation such as stick -slip phenomenonand theeffect caused by the initial position of elements are revealed.
ANALYSIS BY MEANS OF SIMULATION OF THERMAL AND WIND ENVIRONMENT OF ADOBE VERNACULAR ARCHITECTURE GROUP IN MOROCCO.
Gakuho Morikawa, Kiyotaka Deguchi
Received: March 9, 2013    PDF    Abstract
This paper deal with the analysis by means of simulations of thermal and wind environment of adobe vernacular architecture group called ‘Ksar’in Morocco. Most of Ksar is in desert area with a wide range of temperature and near the oasis. It is thought that the indoor environment in Ksar were done by CFD, and the evaluations by SET* were compared to the observed data.
COOLING EFFECT OF THE DRY MIST IN A SEMI-OUTDOOR SPACE - EXPERIMENT AND CFD SIMULATION-
Nonaka Atsushi, Deguchi Kiyotaka
Received: March 9, 2013    PDF    Abstract
This study validates the cooling effect of the dry mist in a semi -outdoor space by experiment and simulation. In the experiment to validate the measuring point measured nine locations have different height and position measurements of temperature and humidity, whether there is a different in the cooling effect due to the difference in height and position. Then, simulation and verification based on the measured value.
A Study on Structural Vibration Property by Optimization Method ―Structural Identification from Microtremor―
Midori Koiwai, Taiju Hamasaki, Nagayuki Yoshida
Received: March 9, 2013    PDF    Abstract
In recent years, people’s concern about earthquake -proof is increasing from the reason of falsification of earthquake- resistance data and a great earthquake disaster etc. The purpose of this study is to build the process that identifies structure quantity by the microtremor observation data. On this method, we can reduce cost and time, and that seismic judgment without drawing and specification. Additionally, we can know a state of deterioration due to aging or long us age.The observed structure is the low -rise story of ’58 building at Ichigaya campus of Hosei University. This paper develops a new process on structural identification.
Analysis of Incident and Reflected field by FEM and CIP Method in 1D model
Soichiro Kanzaki, Yutaka Sasaki, Seungyun Shin, Tomotaka Yanagawa, Nagayuki Yoshida
Received: March 9, 2013    PDF    Abstract
When we analyze wave propagation, we should model the ground as if it is extended infinitely in the limited analytical region. Now we try to make infinite ground model by FEM and CIP method. CIP method is usually used to analyze sound, noise and electromagnetic field. In this research, we try to build both Incident field and Reflected field at the same time. When we can analyze both of field, it is able to chase the all the details of earthquake motion.
Study on Analysis of 2D Radiation Field by CIP Method
Yutaka Sasaki, Soichiro Kanzaki, Seungyun Shin, Tomotaka Yanagawa, Nagayuki Yoshida
Received: March 9, 2013    PDF    Abstract
When we analyze wave propagation, we should model the ground as if it is extended infinitely in the limited analysis region. We can make the infinite ground model by CIP method. This method is usually used to analyze sound, noise and electromagnetic field. In this research, But, we use it to model the ground motion. We introduce polar coordinate system to get the theoretical solution more precisely. This solution is compared with the numerical results. In this paper we aim to investigate 2-dimensional radiation field by CIP method.
Substituent Effects on the Gas - Phase Acidities of Phenylacetic Acids
Kazuhide Nakata, Mizue Fujio, Kichisuke Nishimoto, Yuho Tsuno
Received: March 9, 2013    PDF    Abstract
Relative gas -phase acidities of ring -substituted phenylacetic acids were theoretically determined using proton transfer equilibria. Substituent effects of this system were compared with those on the gas -phase acidities of benzoic acids. It was shown that the gas -phase acidities of phenylacetic acids are governed by three kinds of electronic effects: the inductive, resonance, and saturation effects, and the through -conjugation in phenylacetate anions is slightly larger than that in benzoate anions. Following substituent effect analysis with an extended Yukawa -Tsuno equation,ΔEX = ρ(σ0 + rΔσR + sΔσS) , confirms the above results giving an excellent linear correlation. Conformational analyses show that the slightly larger through -conjugation in phenylacetate anions can be attributed to the hyperconjugation between acetate moiety and benzene π-electron system.
Three-Dimensional Structural Model and Earthquake Resistance Analysis -Ichigaya -Tamachi Campus of Hosei University-
Shunya Kaneko, Yohei Hodoshima, Nagayuki Yoshida
Received: March 11, 2013    PDF    Abstract
In this study, considering the vibrational characteristics of the ground and a building, we analyze the main story in Ichigaya Tamachi Campus. This study has two processes. The first process consists of the microtremor observation and 3D FEM analys is. We decide the natural periods from the vibration data obtained by the microtremor observation. We calculate several natural periods and investigated the vibrational behavior of the building by the 3D FEM analysis. Finally, we show the comparison between the observational data and the analytical results. The second process has dynamic response analysis using the shear mass system model which is made in detail from the drawings of the building. Then inputting the real seismic waves, we carry out the dynamic response analysis based on the incremental type method of Runge-Kutta which makes it possible to examine the seismic capacity of the building.