Transverse two-phase flow around a cylindrical heat exchange surface

Particle motion and deposition are modelled numerically on an infinite transversely streamlined cylinder subjected to force factors of a non-turbulent nature.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 59, No. 6, pp. 917–923, December, 1990.     

Radiative-convective heat transfer in a system of two porous plates

Academic Science Complex, A. V. Lykov Institute of Heat and Mass Transfer, Academy of Sciences, Belorussia, Minsk. Translated from Inzhenerno-fizicheskii Zhurnal, Vol. 62, No. 1, pp. 95–101, January, 1992.     

Critical review of available correlations for two-phase flow heat transfer of ammonia

Although ammonia has been used for decades as a refrigerant of choice for selected large- and small-scale applications, no formal database is available on heat transfer of ammonia. A critical review of the published literature on heat transfer of ammonia is provided in this paper. The available correlations for in-tube and external boiling/evaporation and condensation heat transfer of ammonia are discussed and evaluated where possible. Supported by the findings of this effort, research areas of relevance that can contribute to expanded use of ammonia as an environmentally friendly refrigerant are suggested.     

Radiative-convective heat transfer of a spherically shaped space vehicle in carbon dioxide

A system of equations of motion of viscous, heat-conducting, chemically nonequilibrium, and selectively radiating and absorbing gas is used for solving the problem of radiative-convective heat transfer of a space vehicle of the simplest (spherical) shape in carbon dioxide used for simulating the Mars atmosphere. Comparison is made of the convective and radiative heating of the entire surface of the space vehicle (from forward to rear stagnation point) for the typical conditions of entry of space vehicles into the Mars atmosphere, in particular, for individual points of the Pathfinder trajectory. It is demonstrated that, in some regions of space vehicle entry into the atmosphere, the radiative thermal heating of some elements of space vehicle surface may exceed the convective thermal heating. There is also demonstrated the need for analysis of the level of radiation heat fluxes on the entire surface of the Mars-bound space vehicle rather than on its frontal surface alone.     

Mean heat transfer in transverse air flow around a cylinder

A modified method of analyzing experimental data is outlined, allowing the degree of linearity of the relation between the Reynolds and Nusselt numbers to be determined.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 59, No. 4, pp. 648–649, October, 1990.     

Finite element solutions for laminar flow and heat transfer around a square prism

Abstract

The finite element solutions of Navier‐Stokes and energy equations for steady laminar flow and heat transfer around square prisms, with attack angles of 0° and 45° have been obtained for a gas of Pr=0.7. The variations of surface shear stress, local pressure and Nusselt number are obtained over the entire prism surface including the zone beyond the point of separation. The predicted values of drag coefficients, the location of. separation, the average Nusselt number and the plots of velocity flow fields and isotherms are also presented. The trend of the present numerical results seems reasonable.     

An approximate mathematical model of heat and mass transfer in two-phase flow

We propose an approximate method for studying transport processes in one-dimensional two-phase flow which permits the determination of the system output as a function of input and the system parameters. The error of the method is estimated.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 34, No. 4, pp. 673–683, April, 1978.     

Control of supersonic flow around bodies by means of a pulsed heat source

The influence of an external, pulse-periodic, energy supply source on the aerodynamic characteristics of a hemisphere positioned downstream is simulated. Pis’ma Zh. Tekh. Fiz. 23, 1–8 (May 12, 1997)     

Flow and heat transfer in coaxial jet flow around an obstacle

Results are presented of an experimental investigation of the gasdynamics and heat transfer in the reverse flow zone near an obstacle during coaxial jet flow on it along the normal.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 38, No. 1, pp. 38–43, January, 1960.     

Radiation heat transfer in two-phase media

The state of the art of approximate and numerical methods of the theory of radiation heat transfer is analyzed. The principles for producing engineering methods of computing the radiation heat-transfer characteristics in power plants are examined.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 53, No. 5, pp. 807–814, November, 1987.     

Convective heat transfer coefficients for near-horizontal two-phase flow of nitrogen and hydrogen at low mass and heat flux

Correlations for convective heat transfer coefficients are reported for two-phase flow of nitrogen and hydrogen under low mass and heat flux conditions. The range of flowrates, heat flux and tube diameter are representative of thermodynamic vent systems (TVSs) planned for propellant tank pressure control in spacecraft operating over long durations in microgravity environments. Experiments were conducted in normal gravity with a 1.5° upflow configuration. The Nusselt number exhibits peak values near transition from laminar to turbulent flow based on the vapor Reynolds number. This transition closely coincides with a flow pattern transition from plug to slug flow. The Nusselt number was correlated using components of the Martinelli parameter and a liquid-only Froude number. Separate correlating equations were fitted to the laminar liquid/laminar vapor and laminar liquid/turbulent vapor flow data. The correlations give root-mean-squared (rms) prediction errors within 15%.     

Linear heat transfer in a flow around a cylinder or a sphere

It is shown that the relation between the Nusselt and Reynolds numbers determined by the Reynolds analogy is linear with self-similarity of the hydrodynamic resistance coefficient.Special Design and Technology Office Element, Odessa, Ukraine. translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 68, No. 3, May–June, pp. 395–396, 1995.     

Radial-conductive heat transfer of semitransparent bodies

A method is proposed for calculating the nonsteady radiative-conductive heat transfer of semitransparent bodies in the non-one-dimensional case, on the basis of the Monte Carlo method and the finite-difference method.Translated from Inzhen-erno-fizicheskii Zhurnal, Vol. 61, No. 4, pp. 680–684, October, 1991.     

Critical heat flux for two-phase flow of helium I

This paper describes a study performed to obtain the critical heat flux data on liquid helium I in a vertical tube under forced convection. The pressure of the fluid ranges from 1.1 to 2.0 atm (from 0.11 to 0.20 MN m^?2), and the quality up to 1. The results show that the critical heat flux decreases with increasing pressure and quality.     

Downward two-phase flow applications for a non-conventional heat pump

A non-conventional heat pump working by a difference in density between two branches of a hydraulic vertical loop has been described. This system called thermogravimetric heat pump, TGHP, operates with a non-conventional regenerative thermodynamic cycle which remarkably improves COP values. The lower density in the ‘downward branch’ is obtained by a liquid–vapour two-phase flow. Performances and main geometrical characteristic trends, such as plant height Z and two-phase column diameter D_T–PD have been drawn, varying the minimum cycle temperature between 15 and 25 °C and the user temperature, T_max, in the range 60–70 °C. The carrier fluid is demineralized water; according to the peculiar working fluid—PP 50, HFC 134a and HFC 338cca—different solutions can be obtained, such as for 10–12 storey buildings or for skyscrapers. Yet, the results obtained with HFC 338cca must be accepted with some cautions while waiting for a better characterisation of such fluid. Chemical compatibility, thermal stability, environmental impact have been also taken into account in the choice of the operating couple, carrier fluid—working fluid. While the thermodynamic conversion process is non-conventional, the TGHP can be assembled by standardised technology. The compressor of a conventional plant is here replaced by a feeding pump and COP values obtained through a regenerative TGHP are globally larger than those of a common heat pump.     

Heat transfer between solid bodies and high-temperature gas flows

A method based on the solution of a linearized third-order heat-conduction equation is proposed for the determination of intense thermal fluxes.Deceased.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 34, No. 6, pp. 1117–1121, June, 1978.     

Limiting heat transfer in horizontal two-phase thermosiphon

Experimental results on the heat-transfer crisis in a horizontal thermosiphon with steam heating are outlined.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 58, No. 1, pp. 63–67, January, 1990.     

Investigation of heat transfer in transverse flow of a high-temperature dust-gas past a cylinder

The results of experimental determinations of the effective coefficient of heat transfer at the front surface (in the region of the forward critical point) of a cylinder with a high-temperature dust-gas flow are presented. A formula is obtained to determine the relative (in comparison with a pure gas) intensity of heat transfer.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 18, No. 3, pp. 397–402, March, 1970.     

Electrochemical method of studying heat transfer between a cylinder and a rising two-phase flow

An electrochemical method is used to study the mean coefficients of mass transfer, and it is shown that the experimental data are in complete agreement with a relationship [Eq. (2)] derived from experiments with thermal models.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 30, No. 1, pp. 92–95, January, 1976.     

Convective heat transfer in air flow around a cylinder at low Reynolds numbers

The principal objective of the present work is to conduct investigations leading to a more complete explanation of heat-transfer processes on the external wall of a heated cylinder in laminar axial flow around it under high pressures. Investigations are aimed at determination of the limits of existence of mixed convection, explanation of the influence of free convection on the disturbances of heat transfer during laminar flow of a medium, and final explanation of intensification of heat-transfer processes occurring in a flow at high pressures. Published in Inzhenerno-Fizicheskii Zhurnal, Vol. 78, No. 6, pp. 163–169, November–December, 2005.