Calculation of thermodynamic functions of aluminum plasma for high-energy-density systems
- PDF / 299,576 Bytes
- 5 Pages / 612 x 792 pts (letter) Page_size
- 82 Downloads / 184 Views
OF GAS DISCHARGE AND PLASMA
Calculation of Thermodynamic Functions of Aluminum Plasma for High-Energy-Density Systems V. V. Shumaev* Bauman Moscow State Technical University, Vtoraya Baumanskaya ul. 5, Moscow, 105005 Russia *e-mail: [email protected] Received July 15, 2015
Abstract—The results of calculating the degree of ionization, the pressure, and the specific internal energy of aluminum plasma in a wide temperature range are presented. The TERMAG computational code based on the Thomas–Fermi model was used at temperatures Т > 105 K, and the ionization equilibrium model (Saha model) was applied at lower temperatures. Quantitatively similar results were obtained in the temperature range where both models are applicable. This suggests that the obtained data may be joined to produce a wide-range equation of state. Keywords: thermodynamic functions, Thomas–Fermi model, Saha model, Saha–Boltzmann equations, aluminum, hot plasma, power units, equation of state DOI: 10.1134/S1063778816090088
INTRODUCTION The existing and future energy systems characterized by high energy densities (specifically, magnetoinertial fusion devices) have a wide range of application: they may be used as particle sources for radioactive waste disposal and in medicine, as an element of a fusion-fission reactor, and in materials science experiments [1–5]. An important feature of these systems is the generation of ultrastrong magnetic fields (~10 4 T at the maximum target compression) [6, 7]. Confinement of the plasma in the central part of the installation and stabilization of probable plasma instabilities, which grow rapidly with time, are important conditions of operation of power units where thermonuclear targets are exposed to high-intensity plasma sources, X-ray radiation, and magnetically accelerated dense plasma fluxes. The physical parameters of the high-temperature plasma of these units are defined, among other factors, by the equation of state of matter. Thus, it becomes necessary to analyze plasma dynamic processes together with the equations of state at different stages of inertial confinement fusion target compression, including high-density ones, or, in other words, in a wide density and temperature range (temperatures from several thousand to a hundred million kelvin and densities ranging from those typical of gases to 104 g/cm3) [1–5]. It is a challenge to construct wide-range equations of state. In the present study, this challenge was overcome in the simplest possible way: thermodynamic functions were obtained on the basis of the ionization
equilibrium model (Saha model) [8–10] and the quantum-statistical model (Thomas–Fermi model) [9–18]. At the boundaries of applicability of these models, the thermodynamic functions were joined. The indicated models are relatively simple and suitable for joining, since both of them yield qualitatively reasonable results well outside the boundaries of the region of applicability [10]. By “equation of state of matter,” we mean the functional dependence on temperature T and density ρ of
Data Loading...
