DESCRIPTION OF A TEST SET FOR 2-D PROCEDURES AND PROGRAMS IN GAS DYNAMICS. PT. 1

Yu. A. Bondarenko, B. L. Vоrоnin, V. I. Delоv, E. N. Zubоv, N. P. Kоvalуоv, S. S. Sокоlоv, V. E. Shmarulin
VANT. Ser. Mat. Mod. Fiz. Proc 1991. Вып.2. С. 3-9.

      A problem set is proposed designed for testing 2-D procedures and programs in gas dynamics. The authors kept in mind that a test problem must have properties similar to those of most typical actual problems. It is desired for the test problem to have an exact solution. The set consists of 15 tests. This part contains the first seven tests while the others are presented in part 2.

      A problem set is proposed designed for testing 2-D procedures and programs in gas dynamics. The authors kept in mind that a test problem must have properties similar to those of most typical actual problems. It is desired for the test problem to have an exact solution. The set consists of 15 tests. The first seven are described in part 1 while this part contains the others.

      Results of the GLOBUS tabular equation of state are given for describing thermodynamic water and vapor properties in a wide temperature and density range. Thermal pressure and energy components are represented by tables on a uniform logarithmic mesh with a bicubic interpolation between the nodes. Potential pressure is given by a cubic spline on a cubic spline on a uniform density mesh for densities less than normal one and on a uniform logarithmic mesh for densities greater than normal one.
      The equation of state describes experimental data for water and porous ice shock compression, thermal expansion and vaporization along with predicted results for the Thomas-Fermi model with quantum and exchange corrections. Thermodynamic water properties are taken for densities and temperatures ranging from 0,001 to 64 g/сm³ and from 300 К to 10⁶ К respectively. An extrapolation beyond the table is provided.
      The GLOBUS may be used in continuum dynamics programs.

      One of possible way for taking into account a directed medium nuklei motion using a multigroup approximation is studied. Formulas are derived for computing neutron interaction group characteristics and multigroup equations are written for a ball and a rotating solid. The approach developed is characterised by group shape dependencies on the direction of a neutron impacting a moving target.

      General design and operation principles are described for the ZURS-ES Complex intended for investigating various equation-of- state. The Complex comprises a program-set to implement various equation-of-state models and to solve different problems including isolinez and adiabat tracings, thermodynamic quantity computations etc. using these equations. The programs are related to each other only through a single parameter organization way, so that Complex- nonoriented programs may be also added. The Complex provides programming automatization tools to write new programs which makes their development easy.

      A mathematical formulation and a numerical method are described for computing electromagnetic field parameters in the vicinity of a strong gamma quantum beam moving through the air. The field characteristics are derived from a 1-D system of equations obtained with a running wave approximation. A system of ionization kinetics equations is solved to find a radiation-induced conduction in the medium. The sources, that is current density of charged particles produced by gamma quanta (electrons and positrons) and air ionization intensity are determined by solving equations with a self-consistent field and a collision integral in the Focker-Plank form. A numerical example is given.

      The paper proposes a hybrid plasma model modification to take into account nonelastic particle collisions leading to changes of ion charge states. Particle recharge and ionization kinetics is described by a collision integral, quasilinear in distribution function, which was obtained using small ion velocity and energy change approximations for nonelastic collisions.
      A numerical solution of a kinetic equation for the plasma ion component is defined by a particle method including a way to account collisions specially developed based on splitting by physical processes. Numerical results are given for two test problems related to recharge kinetics in moving plane plasma flows.