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An algorithm for thermophysical property calculations based on the finiteelement approximation in the thermodynamic plane has been suggested. As an example of using the algorithm, errors in obtaining the compressibility of ethane and its derivatives with respect to reduced density and temperature are discussed.

Scientific and technological problems of the growing of crystalline films from the gas phase are reflected in [1-6]. Here the principal stress is laid on the direct study of the kinetics and properties of the crystal grown, while, at the same time, the design and calculation of the technological growth processes are of a semiempirical character [4-9]. This is explained both by the variety and the complexity of the processes taking place in the gas phase and at the surface of the growing crystal, and by the lack of a rigorous approach to a quantitative description of processes of crystal growth, including the gas and surface phases, in spite of the fact that, in the field of physicochemical gasdynamics~ such statements of the problems do exist [10-12]. For an analysis of the growth of crystals, the problem consists in determination of the functional relationships for heterogeneous reactions, which is impossible without a knowledge of the picture of the distribution of the parameters of the gas phase. Existing attempts to take account of the gasdynamic factors in investigations of the growing of crystals [4-9] are frequently bound up with unjustified assumptions and even with errors. In calculation of mass transfer in gas-transport reactors, use is made of the approximation of infinitely rapid diffusion [6] for the transport of the growing component without justification of the validity of this assumption, or the results of the selfsimilar theory of the boundary layer are used outside the region of their validity (with Reynolds numbers less than unity, in the absence of similarity or se!f~simiiarity) r8 9]

We consider the problem of steady flow of an inviscid, non-heat-conducting gas about a delta wing which is spherically blunted at the nose and cylindrlcally blunded on the leading edges, at an angle of attack.

The p rob lem of hypersonic flow about blunt bodies is considered at an angle of a t t ack . For the n u m e r i c a l solut ion we use the method of [1] wi th sl ight changes . We se lec t new independent var iab les which are more conven ien t for c a l cu l a t i ng the flow about bodies of revo lu t ion of an angle of a t t ack . As the unknowns we consider the pressure and en tha lpy , which s impl i f ies the approx ima t ion of the state equa t ion wi th account for the p h y s i c o e h e m i c a l changes. w presents the de ta i l ed compu ta t i o n a l formulas. w describes the c o m p u t a t i o n a l s cheme for spher ica l ly b lunted cones at an angle of a t t ack . w presents some results of ca lcu la t ions of hypersonic flow about spher ica l ly blunted cones wi th h a l f a n g l e 0 w = 0 ~ 9~ ' a t the angles of a t t a ck c~ = 0, 5 ~ 10 ~ in per fec t (M=~ = ~) and eqn i l ib r inm dissoc ia t ing air . In par t icu la r , results are shown which i l lus t ra te the t i m e of shock appearance on the lee side of a blunt cy l inder at an angle of a t t ack . It is shown in w tha t i t is possible to se lec t spec i a l s imi la r i ty var iables , analogous to the corresponding var iab les in the case of a x i s y m m e t r i c flow, in which the pressure dis t r ibut ion along the g e n era t r ices of a cone with h a l f a n g l e 0 w > a differs on ly by 10%, both wi th respect to the m e r i d i o n a l angles ~ and with respect to the hypersonic flow condit ions. The resul t ing un iversa l curve may be used also for the approx ima te c a l c u l a t i o n of the pressure on the cone at an angle of a t t ack . w We refer the components of the ve loc i ty vector V to the v e l o c i ty V~, and the densi ty p to the f rees t ream densi ty p~, the pressure p and the enthaipy i are referred r e spec t ive ly to the quant i t ies p~ Vz~ and Vz~. We shal l seek the ve loc i ty vector in the cy l ind r i ca l coordina te system x, r, r (Fig. 1) in the form

We examine some characteristics of hypersonic flow past slender blunt bodies of revolution at a small angle of attack α≲τ≪1, where τ is the relative body thickness. It is shown that, within the framework of hypersonic theory, for a correct-consideration of the effect of the conditions in the transitional section between the nose and the lateral surface it is necessary, in the general case, to specify the circumferential distribution of the force effect for the nose and the mass of the gas. For small α, the effect of the nose, just as in two-dimensional flows [1–4], shows up only through its drag coefficient cx, for α=0. On this basis, the similarity law [1–4] for flow past such bodies, with arbitrary form of the lateral surface and differing in the shape of the nose blunting, which is valid over the entire disturbed region, with the exception of a small vicinity of the nose, is extended to the case in question.