Heat and mass transfer under frosting conditions

The effect of frost formation on heat transfer between a test cylinder and its gaseous environment was studied experimentally. The main parameters discussed in the paper are: the total heat flux, the steady-state convective heat transfer coefficient, and the mass of frost adhering to the test cylinder. The emphasis of the paper is on the thermal conducivity of frost. The data indicate that the diffusion mechanisms of moisture transfer within the frost layer causes the frost density and thermal conductivity to increase with time. Frost thermal conductivity is a function of the local temperature and average density. The can be used by designers of low temperature systems with uninsulated surfaces.     

Heat and mass transfer in a field of IR radiation under conditions of swirling flow of an optically active medium

Results are presented of investigations of the heat and mass transfer process under deep oxidation of low-concentration hydrocarbons in a volume of a gas-air optically active medium on a catalyst surface.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 55, No. 3, pp. 369–373, September, 1988.     

Pattern of external heat and mass transfer under vacuum during sublimation processes

It has been shown experimentally that the stream of vapor flowing from the sublimation surface (porous metal plate, ice, capillary-porous body) into vacuum is similar to an immersed discharge jet whose dimensions depend on the heat load and on the vacuum level in the sublimator.Translated from Inzhenerno-Fizieheskii Zhurnal, Vol. 23, No. 3, pp. 424–429, September, 1972.     

An investigation of the processes of heat and mass transfer in a multilayer medium under conditions of injection of a miscible agent with simultaneous electromagnetic stimulation

A numerical investigation is performed of the impact of high-frequency (HF) electromagnetic (EM) field on the process of filtering of miscible fluids and propagation of heat in a uniform stratum. The cross effects of heat and mass transfer, which arise under conditions of nonisothermal motion of a multicomponent medium in porous medium, are taken into account during simulation.     

Heat and mass transfer on a cylinder surface in cross flow under supersaturated frosting conditions

In this paper a semi-empirical model describing heat and mass transfer on a cylinder surface in humid air cross flow under supersaturated frosting conditions is presented. The lack of psychrometric data in the supersaturated zone of the psychrometric chart has historically impeded the ability of researchers to accurately predict heat and mass transfer in supersaturated air. The work described in this paper has been partially made possible by developing a systematic procedure to compute the properties of supersaturated moist air, especially in the low temperature zone of the psychrometric chart. Development of such a capability will allow us to predict the amount of frost collected on a coil, the frost deposition and coil heat transfer rates, frost thickness and frost surface temperature, and other important coil frost parameters under supersaturated conditions.     

Heat and mass transfer under conditions of hydrogen evolution in reactions of amorphous-crystalline alloys with water

We investigate the displacement of hydrogen from water by means of silicon-and-aluminum-based alloys obtained from the inorganic portion of coal. We present a variant of improvement of the process by a change in the structure of the alloys. Attention is mostly paid to external heat transfer between the alloys and aqueous solutions of alkali. State Polytechnic University; Institute for Problems of Mechanical Engineering, National Academy of Sciences of Ukraine, Khar'kov, Ukraine. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 69, No. 6, pp. 1006–1008, November–December, 1996.     

Self-adjoint solution to the problem of heat and mass transfer in a multiphase medium

A self-adjoint solution is obtained to the problem of heat and mass transfer in a multiphase medium, with the flow of the gaseous phase taken into account.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 24, No. 5, pp. 916–920, May, 1973.     

Determination of coefficient of external mass transfer in drying processes

A method is proposed for determining the coefficient of external mass transfer from experimental curves of drying kinetics in porous materials. A comparison of results obtained by this method and by the method of moisture content measurements indicates a close agreement.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 42, No. 4, pp. 599–603, April, 1982.     

Heat and mass transfer in chemically reacting media with decrease in partial pressures of vapor

We present a mathematical model of heat and mass transfer in a chemically reacting medium-multi-component vapor-gas mixture system with decrease in partial pressures of vapor-gas components in a free reactor volume. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 73, No. 5, pp. 1012–1020, September–October, 2000.     

Heat transfer during filtration in a heterogeneous medium with input conditions at a moving boundary

Theoretical results on the heat transfer in combustion-product filtration in the rock-collapse zone behind a borehole-damaged coal bed are outlined. A sufficiently simple engineering solution of the problem is obtained by means of an equivalent heat-conduction equation, and the limiting temperatures corresponding to different parameter values are analyzed.Translated from Inzhenerno-fizicheskii Zhurnal, Vol. 61, No. 2, pp. 313–318, August, 1991.     

Heat transfer in cryogenic liquids under pressure

The dependence of the heat transfer on pressure is studied for a horizontal plane surface in liquid helium, liquid hydrogen, and liquid nitrogen in the range 0.03 < p/p_c < 0.9: a maximum of the maximum heat flux density q?_m,m was found at ～0.35 p_c. For helium, additionally, the dependence on the inclination of the surface against the horizontal was determined.A general representation for the dependence of the reduced maximum heat flux density q?_m/q_m,m on the reduced pressure p/p_c is given which also describes adequately well the results obtained with other cryogenic liquids.     

Axisymmetric problem of heat and mass transfer in saturated porous medium

Self-similar solutions are obtained for the system of heat-conduction and filtration equations in regions separated by a moving boundary in the axisymmetric case.Fortieth-Anniversary-of-the-October-Revolution Pashkir State University.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 38, No. 5, pp. 913–918, May, 1980.     

Mass transfer under conditions of filtration in a randomly inhomogeneous medium

Dispersion phenomena occurring under conditions of filtration in a medium whose porosity and permeability are homogeneous and isotropic random fields are studied. The effective coefficients of hydraulic resistance and the dispersion of the impurity are calculated, and the averaged equations of filtration and convective diffusion are derived.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 51, No. 3, pp. 450–458, September, 1986.     

Heat transfer to an ascending laminar flow of hydrocarbons under supercritical pressure conditions

Some results of experimental investigations of heat transfer of n-heptane in a laminar forced flow under the conditions of supercritical pressures are presented, and equations to estimate the intensity of heat transfer under viscous and viscous-gravitational conditions are suggested. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 79, No. 4, pp. 91–95, July–August, 2006.     

Heat and mass transfer between local combustion sites in metallic powder preforms under thermal-explosion conditions

Measurement of temperatures is made at different points in the volumes of exothermic cells and intervening spacings in model powder metallic preform mixtures during their combustion under thermal-explosion conditions. The presence of temperature gradients is found, as are regularities in their change in interrelation with specific features of migration of eutectics and melts formed in a porous metallic skeleton consolidated in a combustion wave. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 71, No. 3, pp. 387–393, May–June, 1998.     

Heat and mass transfer in a solidfying binary melt under mixed convection with account for turbulence

A generalized mathematical model has been developed for heat transfer and hydrodymanics with account for turbulence in the stages of pouring and subsequent formation of a steel ingot.Donetsk State University, Donetsk, Ukraine. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 67, Nos. 3–4, pp. 202–208, September–October, 1994.     

Heat transfer inside a porous material under nonstationary conditions

The internal heat transfer associated with the cooling of heated porous specimens by cold air has been investigated experimentally.