Heat transfer with boiling of a thin water film on a Teflon surface

An experimental investigation has been made of heat transfer with boiling of a thin water film on a horizontal heat-generating surface, made of Teflon-4.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 34, No. 2, pp. 202–204, February, 1978.     

Heat transfer in nucleate boiling of different low boiling substances

Heat transfer coefficients for nucleate boiling of methane, ethane, ethylene, argon and carbon dioxide were determined using an apparatus for the precise investigation of pool boiling heat transfer in the low temperature range. The apparatus used a horizontal cylinder as the heating element. The influence of the thermophysical properties of the boiling liquid was established by comparing the absolute values of the heat transfer coefficients in a normalized boiling state, i.e. a saturation pressure equal to 10% of the critical pressure and a heat flux density equal to 2 × 10⁴ W m⁻². By including the results for a number of higher boiling liquids, which were investigated previously under similar experimental conditions, and using literature data for three very low boiling liquids, an empirical correlation is established which allows an approximate prediction of the absolute value of the heat transfer coefficient at nucleate boiling for substances of different molecular structure.     

Heat transfer in film boiling on a horizontal surface

Film boiling of a saturated liquid on a horizontal surface facing upwards is considered. An expression for the complex, determining the heat transfer rate, is obtained from the condition of interface stability loss; the relation is finalized by generalizing the experimental data. Two different mechanisms of bubble generation on the surface of a vapor film which account for the character of the derived relation are analyzed.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 63, pp. 259–269, September, 1992.     

Heat transfer in liquid oxygen boiling in a large volume

The heat transfer in liquid oxygen boiling in the temperature range -194 to -153°C at pressures of (0.025–1.08) · 10⁶ N/m² was experimentally investigated. The empirical dependence of the heat-transfer coefficient on thermal flux density and pressure is derived.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 21, No. 2, pp. 276–282, August, 1971.     

Heat transfer from a spherical source in a rarefied gas

The heat-transfer problem from a sphere in a rarefied gas is solved using a model kinetic equation. Diffuse scattering of gas molecules by the sphere surface with arbitrary energy accomodation is assumed.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 39, No. 3, pp. 428–434, September, 1980.     

Heat transfer under conditions of nucleate boiling

New physical concepts are developed in connection with the two fundamental processes resulting in the transfer of heat from a heater to a liquid under conditions of nucleate boiling.     

Heat transfer in boiling neon in vertical capillaries

Values for the burnout heat flux and critical temperature difference are measured in boiling neon on the internal surface area of vertical capillaries. A hysteresis is observed as power increases and decreases, which becomes weaker after several increases of power up to the critical heat flux point. The characteristics of the dependences obtained are discussed.     

Heat transfer for a liquid boiling in a bed of granular material

An approximate analytical model is given for heat transfer during boiling in a bed of granular material, and this is used in a generalization from the published data.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 34, No. 5, pp. 792–798, May, 1978.     

Heat transfer during boiling of a fluid on circumferential fins

Approximate solutions in generalized variables obtained for the temperature profile and thermal flux in an individual circumferential fin cooled by a boiling fluid are compared with experimental data for Freon 113.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol.32, No. 1, pp. 5–12, January, 1977.     

Heat transfer in nucleate boiling (theory)

From a joint solution of the equations describing the individual elementary processes associated with nucleate boiling a theoretical formula is obtained (in criterial form) for the nucleate-boiling heat transfer coefficient of nonmetallic liquids. This formula is compared with the experimental data on water boiling over a broad range of pressures.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 15, No. 5, pp. 809–817, November, 1968.     

Heat transfer in liquid boiling on finned surfaces

Results of an experimental investigation of heat transfer in boiling of water and Freon-113 on cylindrical shells with longitudinal fins are presented.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 22, No. 1, pp. 13–18, January, 1972.     

Heat transfer in boiling of liquid in a film moving under gravity

Experimental data on heat transfer in boiling in a film of liquid moving under gravity have been processed in dimensionless coordinates. A comparison between the data on heat transfer during boiling in a film with the data on heat transfer in pool boiling is carried out, which makes it possible to more accurately estimate the influence of the film flow velocity and spray entrainment on heat transfer in film boiling.     

Heat and mass transfer between a boiling liquid and bubbles

A method is proposed for calculating the flow of a boiling liquid with bubbles through vertical pipes (containers).Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 23, No. 5, pp. 859–867, November, 1972.     

Heat transfer on boiling a Freon-22-dibutyl phthalate solution

Experimental data on the boiling heat transfer of a Freon-22-dibutyl phthalate solution have been obtained on a special apparatus. The dependence of the heat-transfer coefficient on the heat load, pressure, and solution concentration has been established.     

Heat transfer during the boiling of water and Freon-113 at an isothermal surface

An analytical and experimental study has been made of the heat flow modes (of the q=f(_B1) relation) during the boiling of water and Freon-113 at the isothermal surface of a cylindrical stud. The heat flux was supplied through an end surface of the stud and was dissipated off its lateral surface, at which various modes of pool boiling occurred simultaneously. Test data are compared here with analytical calculations.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 19, No. 4, pp. 637–645, October, 1970.     

Heat transfer coefficient during two-phase flow boiling of HFC-134a

This paper reports a study of the evaporation of HFC-134a inside smooth, horizontal tubes. Tests were performed with the pure refrigerant and with oil-refrigerant mixtures. The heat flux was varied from 2 to 10 kW m⁻². The inner diameter of the tubes was 12 mm. Two evaporators were used, 4 and 10 m long, and the oil content was varied from 0 to 2.5 mass percentage (synthetic oil, EXP-0275). Oil-free HFC-134a had a higher heat transfer coefficient than HCFC-22 at the same heat and mass fluxes. The effect of oil in the refrigerant is dependent on the heat flux. At 2 and 4 kW m⁻² the heat transfer coefficient had a maximum value for an oil content of around 0.5 mass percentage; no increase is registered for a heat flux of 6 kW m⁻². The heat transfer coefficients for the pure refrigerant were also compared with two existing correlations. The measured heat transfer coefficients averaged over the evaporator deviate less than 40% from the correlation according to Pierre. The heat transfer coefficients at the short evaporator lie within 20%. The correlation given by Jung overestimates the heat transfer coefficient by approximately 50%.     

Heat transfer and local characteristics for gasoil boiling in a large volume

Measurements have been made on the heat-transfer coefficients, vaporization-center concentration, bubble frequency, and detachment diameters. The amount of heat transported by the vapor bubbles has been determined.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 52, No. 3, pp. 383–386, March, 1987.     

Heat transfer characteristics of tube bundles during boiling in vacuum

Heat transfer during boiling in vacuum was compared experimentally for single tubes, rows of tube, and tube bundles to analyze characteristic properties of vaporization under such conditions. Relations for calculating heat transfer coefficients are proposed.The Far East Higher Naval Engineering School, Vladivostok. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 62, No. 6, pp. 786–791, June, 1992.