| As the most important substance in the earth and one of the dominant components of detonation products of CHNO explosives, equation of state of water at high temperature and pressure has been widely studied. A series of significant progress has been achieved under shock loading, but some problems are still not solved:(1) in the low and medium pressures (below50GPa), the experimental data of shock temperature for water are lacked. Only two data points were reported before, and the results may be questioned because of using two channels pyrometer.(2) the values of the specific heat for shocked water and its dependence with temperature were disputed. Very different equations of state of water were given by different Cy(T) models at high temperature and pressure.(3) the optical window properties of shocked water were not been systematically studied before. In fact, liquid optical window had a certain potential in solving the problem of temperature measurement for opaque metals, it was considered to be a good window material for studying the shocked temperature of porous metals.(4) the data of optical transparency and thermal conductivity of shocked water at high pressure and temperature could be hardly found, however, they are two important parameters for a window material.Due to the influence of the radiation from the residual gas at metal/window interface, as well as the radiation from the shocked optical window itself, the shock temperature measurement of metal is a long-term unsolved tough problem. The former factor has been basically eliminated by polishing the surface of the metal in recent years, but for the porous metals, we would not get an ideal polished surface from porous metals because the pores are the part of them. So the influence of the radiation from the residual gas at the porous metal/window interface could not be eliminated by polishing the surface of the porous metal. Because of this technical bottleneck, the problem of the temperature measurement of the porous metal has not been solved.In order to solve these problems, a series of experimental and theoretical researches were carried on in present thesis, and the conclusions were as follows:1. The optical transparency of shocked water were first obtained in the pressure range of30-50GPa by using two stage light gas gun loading technique. The results showed that, the shocked water was still an optically transparent medium in the visible wavelength when shocked below35GPa. In the pressure range of35-45GPa, the shocked water became optically translucent medium. So the optical absorption properties were need to consider when water was used as an optical window in this pressure range.2. The shock temperature of water in the pressure range of35-50GPa was first obtained. Combined with the shock temperature of water reported by Lyzenga in the pressure range of35-50GPa, the value range of the specific heat and its temperature dependence of shocked water were restricted:(1) below50GPa, the specific heat of shocked water was equal to7.07R.(2) between50GPa and80GPa, the specific heat was related to shocked temperature (Cv=(5.76+3.84×10-4TH)R) because of the influence of the hot electrons and dissociation effect.3. The range of thermal conductivity value for the shocked water was limited by measuring the tantalum metal/water interface temperature. The results showed that the thermal conductivity of shocked water had a linearity relationship with shocked pressure like: Kw=KW0+2.5735pH W/(m·K),(pH<45GPa)4. The shock temperatures of tantalum, copper and iron were measured by using liquid water as an optical window, and it is found the relationship between porous body average thermodynamic temperature value and porous iron/water interface equilibrium temperature. Combined with the three terms equation of state and calculation method for the adiabatic release temperature in the solid-liquid phase, the shock temperature and release temperature of porous iron were calculated. It showed that for porous metal with porosity less than1.3(αc<1.3), the experimental results were consistent with the calculated ones. |
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