抄録
Thermophysical properties of water were studied using molecular dynamics method. Various types of models for water molecule were selected and the results were compared. The simulation was carried out using NPT ensemble, and the pressure was fixed at atmosphere. There is a close relationship between thermophysical properties and the solidification process of supercooled water. In this report, heat capacity, thermal expansion coefficient, isothermal compressibility, self-diffusion coefficient, shear viscosity and thermal conductivity were calculated using various models in the range from normal temperature down to supercooled temperature. Addition to these properties, the latent heat of ice Ih to water was estimated. The models selected in thies report were ST2, TIP4P, CC and SPC/E. When the temperature was high, good agreement was found between each models and the experimental data for almost all properties. However, at low temperature region, the difference from experimental data exists depending on the choice of water models, and all these models in the lowest temperature behave as a solid state. By carrying out the melting simulation of ice Ih under atmospheric pressur using these models, melting points were found to be relatively high compared to the real water, but the latent heats were estimated to be close enough to the experimental data.
