A study of the sorption properties of a composite sorbent prepared from pseudoboehmite and synthetic sodium-borosilicate glass microspheres was performed with the aim of using the sorbent in membrane-sorption processes of helium extraction from natural gas with its simultaneous drying. Experimentally, permeability of the composite sorbent under study with respect to helium and its impermeability to air and methane has been demonstrated. Under experimental conditions, the absolute moisture content of the gas mixture having passed through the sorbent has reduced from 21.1 to 0.013 g/m3. The rate of helium adsorption by the composite sorbent has increased nearly by two orders of magnitude in comparison with the initial microspheres. It was found that the degree of saturation of the sorbent with water vapor had almost no influence on the rate of helium adsorption. A possibility of optimal use of the composite sorbent by combining the process of natural-gas drying from water vapor and the process of helium extraction from natural gas is shown. This possibility permits shortening of the process sequence for natural gas pre-conditioning prior to helium extraction.
A.I. Leontyev, D.O. Onishchenko, and G.A. Arutyunyan
Bauman Moscow State Technical University, Moscow, Russia E-mail: George.arut@yandex.ru
Keywords: thermoelectric generator, internal combustion engine, heat transfer intensification, energy of exhaust gases
Pages: 747–754
The relevance of applying the methods of energy recovery from exhaust gases is substantiated. The principle of operation of a thermoelectric generator is described, the variant of its design is proposed, and the efficiency of various design methods of heat exchange intensification is compared. Designs are compared with a baseline configuration without heat transfer intensifiers in terms of coefficients of gas dynamic resistance ξ/ξ0 and the ratio of dimensionless criteria Nu/Nu0. The results of comparative analysis have proved the applicability of the methods of heat exchange intensification in the design of thermoelectric generators of various vehicles.
O.G. Volokitin1, M.A. Sheremet2, V.V. Shekhovtsov1, N.S. Bondareva2, and V.I. Kuzmin3 1Tomsk State University of Architecture and Construction, Tomsk, Russia 2Tomsk State University, Tomsk, Russia 3Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia E-mail: volokitin_oleg@mail.ru
Keywords: plasma technology, silicate melt, mathematical model, heat transfer, non-Newtonian medium
Pages: 755–765
The article presents the results of theoretical and experimental studies of the production of high-temperature silicate melts using the energy of low-temperature plasma in a conceptually new setup. A mathematical model of unsteady regimes of convective heat and mass transfer is developed and numerically implemented under the assumption of non-Newtonian nature of flow in the melting furnace with plasma-chemical synthesis of high-temperature silicate melts. Experiments on melting silicate containing materials were carried out using the energy of low-temperature plasma. The dependence of dynamic viscosity of various silicate materials (basalt, ash, waste of oil shale) was found experimentally.
The electrical and thermal characteristics of plasma-resistive furnace in the drying zone at a recycling man-made waste were studied. The dependences of power output in the drying zone at different specific electrical resistances of the charge were derived. It is shown that introduction of additional resistance heating in the drying zone reduces the load on plasmatorch, increasing the lifetime of electrodes.
V.Ya. Rudyak1, A.V. Minakov1,2,3, D.V. Guzey1,2, V.A. Zhigarev2, and M.I. Pryazhnikov1,2 1Novosibirsk State University of Architecture and Civil Engineering, Novosibirsk, Russia 2Siberian Federal University, Novosibirsk, Russia 3Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia E-mail: valery.rudyak@mail.ru
Keywords: nanofluid, laminar-turbulent transition, nanoparticles, flow in pipe, hydrodynamic resistance, viscosity
Pages: 773–776
The paper presents experimental data on the laminar-turbulent transition in the nanofluid flow in the pipe. The transition in the flows of such fluids is shown to have lower Reynolds numbers than in the base fluid. The degree of the flow destabilization increases with an increase in concentration of nanoparticles and a decrease in their size. On the other hand, in the turbulent flow regime, the presence of particles in the flow leads to the suppression of small-scale turbulent fluctuations. The correlation of the measured viscosity coefficient of considered nanofluids is presented.
The application of the weighted residuals method is considered for the calculation of heat transfer in flowing thin liquid films. As an example, the problem of the film moving under the action of the gas flow on the heated horizontal wall is solved. The solution demonstrates good agreement with the numerical one obtained by the finite-difference method.
Comparative study of 3D numerical simulation of fluid flow and coal-firing processes was applied for flame combustion of Kansk-Achinsk brown coal in a vortex furnace of improved design with bottom injection of secondary air. The analysis of engineering performance of this furnace was carried out for several operational modes as a function of coal grinding fineness and coal input rate. The preferable operational regime for furnace was found.
August 7, 2016 is the 70th Anniversary of Professor Anatoly A. Maslov, a noted scientist, specialist in viscous gas dynamics, and Doctor of physical and mathematical sciences.
September 8, 2016 is the 50th Anniversary of Alexander N. Shiplyuk, a noted scientist, researcher in the field of high-velocity aerogasdynamics and experimental methods of studying gas flows, doctor of physical and mathematical sciences, corresponding member of the Russian Academy of Sciences.
Professor Anatoly M. Kharitonov, an outstanding researcher in the domain of fluid mechanics, doctor of technical sciences, Honored scientist of the Russian Federation, winner of the Prize of the Council of Ministers of the USSR and of the Prize named after Professor N.E. Zhukovskii, and Deputy Editor-in-Chief of our journal, deceased on August 13, 2016.
