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1305. Experimental investigation of rarefied gas flow around a sphere
Classified abstracts 1301-1600 Classified abstracts 1 3 0 1 - 1 3 1 1 on this page
Editor's note The label immediately following the title of each item denotes country or origin of publication, and that at the end of each abstract indicates country of origin of work (where known).
I. G e n e r a l v a c u u m s c i e n c e and e n g i n e e r i n g 14. KINETIC THEORY OF GASES 14 1301. Computing the pressure profile in a given volume when it is exposed to a constant and exponentially dropping lower pressure through an orifice. (Germany) Pressure-time characteristic in a given volume is studied when the volume is exposed to a constant and exponentially changing lower pressure through an orifice. Solutions are derived assumingisothermal and adiabetic conditions an both the cases Von H Hamacher, Vakuum Tech, 23 (1) 1974, 1-6 (in German). 14 1302. A simplified kinetic description of vibrational relaxation in binary mixture of viscous gases. (USSR) A theoretical description of the process of vibrational relaxation in the binary mixture of viscous gases is presented with account of chemical reaction between the components. E A Gurmuzova, Aerodynamics of Rarefied Gases, Coil, No 6, Leninqrad University 1973, 92-105 (m Russian). 15 FLUID DYNAMICS 15 1303. Electron density behaviour near the axis of a turbulent hypersonic sphere wake. (Canada) Langmuir probes have been used to obtain estimates of electron density close to the ax=s of the turbulent wakes of 6 82 cm (2.7 in.) diameter spheres flown at 4420 m/s (14,500 ft/s) in air atmospheres at 10 torr A brief resume and discussion is given of the principal experamental results. D Heekman et al, CanJPhys, 52 (4), 1974, 355-360 15 1304. Vacuum installation for gas-dynamic investigations. (USSR) A vacuum installation for gas-dynamic (supersonic jet) investigations, distinguished by a far greater economy than its predecessors, is described. In the new system the source of preliminary rarefaction is connected to the vacuum chamber by a tube which becomes wider in the directaon of evacuation; ~t is passed into the chamber and fixed on the same axis as the supersonic nozzle. The edge of the tube divides the gas jet emerging from the nozzle into two flows: central and peripheral The central supersomc flow passes through the tube and is retarded in the latter, after which ~t is drawn out by pumps or e3cctors. The peripheral flow strikes the cryogenic panels of the system and freezes on them. This arrangement enables relatively cheap pumping systems to be used for the preliminary evacuation L A Vasil'ev et al, Soviet Patent, class F 04 b, 37/08 and G 01 m, 9/00, No 377,546, claimed 19/10/70, published 17/4/73 (in Russian). 15 1305. Experimental investigation of rarefied gas flow around a sphere. (USSR) The results of experimental investigation of dastribution of pressure on surface of thermally insulated sphere placed in a flow of rarefied gas in the transitaon range are presented The experiments were performed in a vacuum wand tunnel. N M Bazarnova et al, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad Umversity 1973, 105-113 (m Russian). 15 1306. The Enskog-Chapman distribution function and boundary conditions for the equations of motion. (USSR) A simple, rarefied, weakly noneqmhbnum gas as considered. With the
aid of an integral kinetic equation vahd on solid surface, the conditions on a wall for macroscopical parameters are given. A hypothesis is presented which enables one to obtain the number and character of boundary conditions on the body surface for the aeromechanics equations with the aid of the Enskog-Chapman method. The calculations are performed for mirror Maxwellian reflection and step interaction potential between molecules. V A Tsibarov, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad Unn,ersgty 1973, 78-92 (m Russian). 15 1307. A two-component statistical model for processing of experimental data obtained in rarefied gas. (USSR) A two-component statistical model for handling of aerodynamical coefficients obtained in experiments in vacuum wind tunnel at various incident angles of the object is presented. E V Alekseeva and R N Mirashin, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad Unwersity 1973, 5-8 (in Russian) 15 1308. Accommodation coefficients as random values. (USSR) Present tables of experimentally determined accommodation coefficients contain values with considerable spread so that these values can be treated as random values. It is shown the accommodation coefficient values determined experimentally in the free-molecular flow conditions possess uniform distribution. The parameters of this distribution are given. V D Vapve, Aerodynamics of Rarefied Gases, Coil, No 6, 1973, 8-10
(m Russian). 15 1309. Construction of the replacement body on the basis of statistical processing of experimental data obtained in rarefied gas. (USSR) The replacement body, formed by the basic body with thickness of boundary layer, is determined on the basis of statistical processing of experimental data on aerodynamical behaviour of the basic body in flow of rarefied gas. N V Vasileva, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad University 1973, 10--12 (in Russian). 15 1310. Similarity of macroparameters in models of gas interaction with surface. (USSR) The problem of broadening of the choice of macroparameters of similarity in rarefied gas dynamics is discussed. The parameters, as the mean value and direction of reflected particles and dispersion characteristics, which are related with the law of gas anteraction with surface, are considered Two models of gas interaction with solid surface are presented which are based on experimental and theoretical data. R G Barantsev and V M Fedorova, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad University 1973, 13-19 (in Russian). 15 1311. Free-molecular interpretation of cylinders for ray reflection along the normal. (USSR) The ray model of reflection of atoms from surface, preserving the average characteristics of reflection, is used for calculation of interaction between parallel cylinders in the hypersonic free-molecular flow. The case is considered for zero reflection angle and constant value of reflection velocity. E V Alekseeva et al, Aerodynamws of Rarefied Gases, Coil, No 6, Leningrad University 1973, 19-28 (in Russian). 405
Editor's note The label immediately following the title of each item denotes country or origin of publication, and that at the end of each abstract indicates country of origin of work (where known).
I. G e n e r a l v a c u u m s c i e n c e and e n g i n e e r i n g 14. KINETIC THEORY OF GASES 14 1301. Computing the pressure profile in a given volume when it is exposed to a constant and exponentially dropping lower pressure through an orifice. (Germany) Pressure-time characteristic in a given volume is studied when the volume is exposed to a constant and exponentially changing lower pressure through an orifice. Solutions are derived assumingisothermal and adiabetic conditions an both the cases Von H Hamacher, Vakuum Tech, 23 (1) 1974, 1-6 (in German). 14 1302. A simplified kinetic description of vibrational relaxation in binary mixture of viscous gases. (USSR) A theoretical description of the process of vibrational relaxation in the binary mixture of viscous gases is presented with account of chemical reaction between the components. E A Gurmuzova, Aerodynamics of Rarefied Gases, Coil, No 6, Leninqrad University 1973, 92-105 (m Russian). 15 FLUID DYNAMICS 15 1303. Electron density behaviour near the axis of a turbulent hypersonic sphere wake. (Canada) Langmuir probes have been used to obtain estimates of electron density close to the ax=s of the turbulent wakes of 6 82 cm (2.7 in.) diameter spheres flown at 4420 m/s (14,500 ft/s) in air atmospheres at 10 torr A brief resume and discussion is given of the principal experamental results. D Heekman et al, CanJPhys, 52 (4), 1974, 355-360 15 1304. Vacuum installation for gas-dynamic investigations. (USSR) A vacuum installation for gas-dynamic (supersonic jet) investigations, distinguished by a far greater economy than its predecessors, is described. In the new system the source of preliminary rarefaction is connected to the vacuum chamber by a tube which becomes wider in the directaon of evacuation; ~t is passed into the chamber and fixed on the same axis as the supersonic nozzle. The edge of the tube divides the gas jet emerging from the nozzle into two flows: central and peripheral The central supersomc flow passes through the tube and is retarded in the latter, after which ~t is drawn out by pumps or e3cctors. The peripheral flow strikes the cryogenic panels of the system and freezes on them. This arrangement enables relatively cheap pumping systems to be used for the preliminary evacuation L A Vasil'ev et al, Soviet Patent, class F 04 b, 37/08 and G 01 m, 9/00, No 377,546, claimed 19/10/70, published 17/4/73 (in Russian). 15 1305. Experimental investigation of rarefied gas flow around a sphere. (USSR) The results of experimental investigation of dastribution of pressure on surface of thermally insulated sphere placed in a flow of rarefied gas in the transitaon range are presented The experiments were performed in a vacuum wand tunnel. N M Bazarnova et al, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad Umversity 1973, 105-113 (m Russian). 15 1306. The Enskog-Chapman distribution function and boundary conditions for the equations of motion. (USSR) A simple, rarefied, weakly noneqmhbnum gas as considered. With the
aid of an integral kinetic equation vahd on solid surface, the conditions on a wall for macroscopical parameters are given. A hypothesis is presented which enables one to obtain the number and character of boundary conditions on the body surface for the aeromechanics equations with the aid of the Enskog-Chapman method. The calculations are performed for mirror Maxwellian reflection and step interaction potential between molecules. V A Tsibarov, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad Unn,ersgty 1973, 78-92 (m Russian). 15 1307. A two-component statistical model for processing of experimental data obtained in rarefied gas. (USSR) A two-component statistical model for handling of aerodynamical coefficients obtained in experiments in vacuum wind tunnel at various incident angles of the object is presented. E V Alekseeva and R N Mirashin, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad Unwersity 1973, 5-8 (in Russian) 15 1308. Accommodation coefficients as random values. (USSR) Present tables of experimentally determined accommodation coefficients contain values with considerable spread so that these values can be treated as random values. It is shown the accommodation coefficient values determined experimentally in the free-molecular flow conditions possess uniform distribution. The parameters of this distribution are given. V D Vapve, Aerodynamics of Rarefied Gases, Coil, No 6, 1973, 8-10
(m Russian). 15 1309. Construction of the replacement body on the basis of statistical processing of experimental data obtained in rarefied gas. (USSR) The replacement body, formed by the basic body with thickness of boundary layer, is determined on the basis of statistical processing of experimental data on aerodynamical behaviour of the basic body in flow of rarefied gas. N V Vasileva, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad University 1973, 10--12 (in Russian). 15 1310. Similarity of macroparameters in models of gas interaction with surface. (USSR) The problem of broadening of the choice of macroparameters of similarity in rarefied gas dynamics is discussed. The parameters, as the mean value and direction of reflected particles and dispersion characteristics, which are related with the law of gas anteraction with surface, are considered Two models of gas interaction with solid surface are presented which are based on experimental and theoretical data. R G Barantsev and V M Fedorova, Aerodynamics of Rarefied Gases, Coil, No 6, Leningrad University 1973, 13-19 (in Russian). 15 1311. Free-molecular interpretation of cylinders for ray reflection along the normal. (USSR) The ray model of reflection of atoms from surface, preserving the average characteristics of reflection, is used for calculation of interaction between parallel cylinders in the hypersonic free-molecular flow. The case is considered for zero reflection angle and constant value of reflection velocity. E V Alekseeva et al, Aerodynamws of Rarefied Gases, Coil, No 6, Leningrad University 1973, 19-28 (in Russian). 405