Equation of state of a partially homogenized plasma of low-dense porous matter

Abstract

The equation of state (EOS) of a low-density porous substance plasma is proposed in the form of continuous media EOS containing, as a pressure control parameter, the degree of plasma homogenization. This parameter is a function of the initial porous structure as well as the current values of plasma density and temperature. Using the partially homogenized-plasma EOS, an approximate analytical solution is found and numerical calculations were performed of the problem of thermal expansion of a flat layer of porous matter. The features of the obtained results are discussed in comparison with the case of a homogeneous substance of equivalent chemical composition. The proposed equation of state is used to analyze the experimental data on thermodynamic state of porous substance heated with laser and x-ray pulses as well as energy transfer in such a substance by laser-supported ionization wave.

High-brightness betatron emission from the interaction of a sub picosecond laser pulse with pre-ionized low-density polymer foam for ICF research

“…Two-dimensional hydro-dynamic simulations were performed for 2 mg/cm 3 450 µm thick foam layer irradiated with a ns pulse of 10 13 W/cm 2 intensity and 3 ns pulse duration using NUTCY-F code [46]. The code accounts for the characteristics of the foam structure, laser radiation absorption and the hydrodynamic and thermal energy transfer in partially homogenized plasma [47][48][49]. The resulting plasma profile that has been established to the moment of the sub-ps pulse arrival, consists of an underdense part, a density up-ramp in front of the shock and of an unperturbed by the ns pulse part with initial foam density (Fig.…”

“…The NUTCY-F code is one of the versions of the NUTCY Eulerian code [55] for the modelling of laser-plasma hydrodynamics in an axisymmetric geometry. The NUTCY-F code uses the equation of state of partially homogenized plasma [49], which takes into account the contribution to pressure from only the homogenized part of matter. The non-homogenized plasma, which participates in the turbulent motion inside the pores, does not contribute to the pressure.…”

High-brightness betatron emission from the interaction of a sub picosecond laser pulse with pre-ionized low-density polymer foam for ICF research

“…Two-dimensional hydrodynamic simulations were performed for 2 mg/cm 3 450 µm thick foam layer irradiated with a ns pulse of 10 13 W/cm 2 intensity and 3 ns pulse duration using NUTCY-F code 46 . The code accounts for the characteristics of the foam structure, laser radiation absorption and the hydrodynamic and thermal energy transfer in partially homogenized plasma [47][48][49] . The code uses the equation of state of partially homogenized plasma described in 49 , which considers the contribution to pressure from only the homogenized part of matter (for more details see "Methods").…”

“…The code accounts for the characteristics of the foam structure, laser radiation absorption and the hydrodynamic and thermal energy transfer in partially homogenized plasma [47][48][49] . The code uses the equation of state of partially homogenized plasma described in 49 , which considers the contribution to pressure from only the homogenized part of matter (for more details see "Methods").…”

“…(2) www.nature.com/scientificreports/ It is assumed that the non-homogenized part of the plasma does not contribute to pressure and electronic thermal conductivity. The pressure P ph in HD equations of motion and energy and thermal diffusion coefficient χ ph in HD equation of motion are calculated from the corresponding values of a completely homogenized plasma as P ph = H•P h and χ ph = H•χ h 49 .…”