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This paper presents a detailed review of the numerical modeling of inductively coupled air plasmas under local thermodynamic equilibrium and under chemical non‐equilibrium. First, the physico‐chemical models are described, i.e. the thermodynamics, transport phenomena and chemical kinetics models. Particular attention is given to the correct modelling of ambipolar diffusion in multi‐component chemical non‐equilibrium plasmas. Then, the numerical aspects are discussed, i.e. the space discretization and iterative solution strategies. Finally, computed results are presented for the flow, temperature and chemical concentration fields in an air inductively coupled plasma torch. Calculations are performed assuming local thermodynamic equilibrium and under chemical non‐equilibrium, where two different finite‐rate chemistry models are used. Besides important non‐equilibrium effects, we observe significant demixing of oxygen and nitrogen nuclei, which occurs due to diffusion regardless of the degree of non‐equilibrium in the plasma.

The Fay and Riddell (F–R) formula is an empirical equation for estimating the stagnation-point heat flux on noncatalytic and fully catalytic surfaces, based on an assumption of equilibrium. Because of its simplicity, the F–R has been used extensively for reentry flight design as well as ground test facility applications. This study aims to investigate the uncertainties of the F-R formula by considering velocity gradient, chemical species at the boundary layer edge, and the thermochemical nonequilibrium (NEQ) behind the shock layer under various hypersonic NEQ flow environments.

The stagnation-point heat flux calculated with the F–R formula was evaluated by comparison with thermochemical NEQ calculations and existing flight experimental values.

The comparisons showed that the F–R underestimated the noncatalytic heat flux, because of the chemical composition at the surface. However, for fully catalytic heat flux, the F–R results were similar to values of surface heat flux from thermochemical NEQ calculations, because the F–R formula overestimates the diffusive heat flux. When compared with the surface heat flux results obtained from flight experimental data, the F–R overestimated the fully catalytic heat flux. The error was 50% at most.

The results provided guidelines for the F–R calculations under hypersonic flight conditions and for determining the approximate error range for noncatalytic and fully catalytic surfaces.

AT temperatures commonly attained in the reaction of liquid propellents at operative pressures in rocket combustion chambers, the significant gaseous end products can be shown to consist at chemical equilibrium of some or all of the following types: H2O, CO2, N2, CO, H2, O2, OH, NO, H, O, N and (rarely) C‐gaseous. The concentrations of these constituents are dependent, for a given propellent combination, upon the temperature (and to a less extent the pressure) conditions under which the reaction proceeds to equilibrium. Thus at temperatures below 2,500°K., the products H2O, CO2, N2 alone are of significance for the case of oxygen balance, whilst to these are added O2 for the oxygen excess case, and CO and H2 for oxygen deficit. The other products are formed by dissociation of these, and their concentrations increase sharply as the temperature rises above some 2,700°K.

We present the finite element simulations of reactive mineral‐carrying fluids mixing and mineralization in pore‐fluid saturated hydrothermal/sedimentary basins. In particular we explore the mixing of reactive sulfide and sulfate fluids and the relevant patterns of mineralization for lead, zinc and iron minerals in the regime of temperature‐gradient‐driven convective flow. Since the mineralization and ore body formation may last quite a long period of time in a hydrothermal basin, it is commonly assumed that, in the geochemistry, the solutions of minerals are in an equilibrium state or near an equilibrium state. Therefore, the mineralization rate of a particular kind of mineral can be expressed as the product of the pore‐fluid velocity and the equilibrium concentration of this particular kind of mineral. Using the present mineralization rate of a mineral, the potential of the modern mineralization theory is illustrated by means of finite element studies related to reactive mineral‐carrying fluids mixing problems in materially homogeneous and inhomogeneous porous rock basins.

Numerical methods are used to solve double diffusion driven reactive flow transport problems in deformable fluid‐saturated porous media. In particular, the temperature dependent reaction rate in the non‐equilibrium chemical reactions is considered. A general numerical solution method, which is a combination of the finite difference method in FLAC and the finite element method in FIDAP, to solve the fully coupled problem involving material deformation, pore‐fluid flow, heat transfer and species transport/chemical reactions in deformable fluid‐saturated porous media has been developed. The coupled problem is divided into two sub‐problems which are solved interactively until the convergence requirement is met. Owing to the approximate nature of the numerical method, it is essential to justify the numerical solutions through some kind of theoretical analysis. This has been highlighted in this paper. The related numerical results, which are justified by the theoretical analysis, have demonstrated that the proposed solution method is useful for and applicable to a wide range of fully coupled problems in the field of science and engineering.

An aerothermodynamic design code for axisymmetric projectiles has been developed using a viscous‐inviscid interaction scheme. Separate solution procedures for the inviscid and the viscous (boundary layer) fluid dynamic equations are coupled by an iterative solution procedure. Non‐equilibrium, equilibrium and perfect gas boundary layer equations are included. The non‐equilibrium gas boundary layer equations assume a binary mixture (two species; atoms and molecules) of chemically reacting perfect gases. Conservation equations for each species include finite reaction rates applicable to high temperature air. The equilibrium gas boundary layer equations assume infinite rate reactions, while the perfect gas equations assume no chemical reactions. Projectile near‐wall and surface flow profiles (velocity, pressure, density, temperature and heat transfer) representing converged solutions to both the inviscid and viscous equations can be obtained in less than two minutes on minicomputers. A technique for computing local reverse flow regions is included. Computations for yawed projectiles are accomplished using a coordinate system transformation technique that is valid for small angle‐of‐attack. Computed surface pressure, heat transfer rates and aerodynamic forces and moments for 1.25 &le Mach No. &le 10.5 are compared to wind tunnel and free flight measurements on flat plate, blunt‐cone, and projectile geometries such as a cone‐cylinder‐flare.

A two dimensional time‐dependent Navier Stokes formulation that encompasses aspects from both the LES formalism and the conventional k‐ε approaches was employed to calculate a range of reacting bluff‐body flows exhibiting high or low level large scale structure activity. Extensive regions of local flame extinction found in these bluff‐body flame configurations were treated with a partial equilibrium/two‐scalar exponential PDF combustion submodel combined with a local extinction criterion based on a comparison of the turbulent Damkohler number against the ratio of the scalar scale to the reaction zone thickness. A dual‐mode description, burning/ non‐burning, of combustion provided the local gas state. Comparisons between calculations and measurements indicated the ability of the method to capture all the experimentally observed variations in the momentum and reactive scalar mixing fields over a range of operating conditions from the lean to the rich blow‐out limit.

The purpose of this paper is to present the more accurate estimation of aero-heating for the ablative 3-D noses by using the viscous shock layers and similarity of viscous boundary layer methods.

The combination of viscous shock layer, similarity of viscous boundary layer (SVBL) methods, Park ablation and Baldwin–Lomax turbulent models is presented in this paper. The proposed method reduces computational memory and run time as compared to the time marching algorithms during flight trajectory. Therefore, the space marching algorithm and finite difference method is used, and the governing equations are transferred into curvature coordinate by using the mapping terms.

The solving for an ogive nose during flight trajectory shows that the convergence of this technique is fast as compared to the user defined function based on the fluent solvers, program to axisymmetric regular geometry code and other research. The results of this research are validated by the mentioned research studies. The relative error for the aero-heating, species concentration of the shock layer gas mixture because of dissociation/ionization of air and surface ablation results is less than 6, 5 and 11 per cent, respectively.

The required time for an aerodynamic design of hypersonic noses reduces as the induced aero-heating is one of the principal design parameters in standpoint aerodynamic, structural and other terms. The magnitude of this parameter, surface temperature and surface recess because of ablation should be corrected during flight trajectory.

The results of this research are applicable for aerospace industries.

The originality of this paper is 90 per cent.

PART VI Practical chemistry textbooks and miscellaneous books. Thirty‐nine practical chemistry textbooks were received from publishers for this part of the review and they have been briefly analyzed under the headings Physical, Inorganic, Organic, Quantitative analysis, and Other features, in Tables 1–4. It has not been possible to examine these in the same detail as the theory books previously considered. A number of other books which are used at ‘A/S’ level were also received and these have been tabulated: problem and calculation books in Table 5, and others in Table 6.