A new computational technique for re-entry flow calculations based upon a shock-fitting technique for unstructured grids

An in-house developed, 2D/3D unstructured CFD solver has been extended to deal with a mixture of thermally perfect gases in chemical non-equilibrium. The Euler equations have been coupled with a state-to-state kinetic model for argon plasma. The spatial discretization uses compact stencil Residual Distribution Schemes and shock waves can be modelled using either shock-capturing or shock-fitting. Promising results have been obtained using the shock-fitting approach for a 2D hypersonic flow past the fore-body of a circular cylinder

A Hierarchical Approach for Fast and Accurate Equilibrium Calculation

In the present paper an improved stoichiometric algorithm based on the successive single reaction equilibrium has been described, avoiding the solution of large systems. The algorithm calculates the equilibrium composition adding automatically suitable new reactions to improve the convergence. The algorithm has been tested for plasma composition calculation for a pure nitrogen and air plasma mixtures. The algorithm proposed always converges and it is significantly faster than other hierarchical algorithms

Statistical thermodynamic description of H2 molecules in normal ortho/para mixture

In this paper, an expression for the internal partition function of normal hydrogen has been obtained starting from the principles of classical statistical thermodynamics. The calculated contribution applies to ideal gas properties. Particular attention has been devoted to the entropy, which depends on the logarithm of the partition function. Comparison between normal and equilibrium hydrogen together with theoretical and experimental data available in literature has been discussed. Tables of the thermodynamic properties of hydrogen and hydrogen ion are also reported

Fundamental Aspects of Plasma Chemical Physics: Thermodynamics

Fundamental Aspects of Plasma Chemical Physics - Thermodynamics develops basic and advanced concepts of plasma thermodynamics from both classical and statistical points of view. After a refreshment of classical thermodynamics applied to the dissociation and ionization regimes, the book invites the reader to discover the role of electronic excitation in affecting the properties of plasmas, a topic often overlooked by the thermal plasma community. Particular attention is devoted to the problem of the divergence of the partition function of atomic species and the state-to-state approach for calculating the partition function of diatomic and polyatomic molecules. The limit of ideal gas approximation is also discussed, by introducing Debye-Huckel and virial corrections. Throughout the book, worked examples are given in order to clarify concepts and mathematical approaches. This book is a first of a series of three books to be published by the authors on fundamental aspects of plasma chemical physics.  The next books will discuss transport and kinetics

Simulazione numerica di plasmi non neutri in una trappola di penning

Dottorato di ricerca in energetica. 12. ciclo. Tutore Gianni Coppa. Coordinatore Michele Cali'Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal