Critical heat fluxes in the pool boiling of liquids at reduced pressure

The authors report the results of a study of the critical heat fluxes and boiling mechanism of certain liquids at reduced pressures.     

Cavitation boiling of various liquids

By studying transient boiling of liquids not heated to the saturation temperature and noise-type boiling of He-II a hypothesis is developed regarding the identity of these phenomena.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 52, No. 6, pp. 893–898, June, 1987.     

Conditions for boiling start in cryogenic liquids

The size of a conical cavity characterizing the start of boiling is estimated on the basis of analyzing the stability of a nucleus of vapor in such a cavity.     

Heat-transfer crisis in the boiling of liquids on microsurfaces

Data is presented on the effect of the dimensions of heaters on the heat-transfer crisis during boiling in a large volume. Relations are obtained to calculate the kinetic loads in the boiling of liquids on microsurfaces.Translated from Inzhenerno-fizicheskii Zhurnal, Vol. 60, pp. 266–270, February, 1991.     

Complex flow in vapour columns over boiling cryogenic liquids

This paper describes heat transfer studies in cold vapour columns with strong vertical temperature gradients. Previous studies had shown that measurements taken using small vertical plates yielded local heat transfer coefficients greater than the predicted Nusselt/Grashof values. A study of flow patterns within the column in the vicinity of these heated plates shows that the heat t transfer measurements obtained from the plates will be complicated by edge effects and local recirculations.     

Experimental study of dynamic effects in bubble boiling of liquids

Results of an experimental study of the principles of the transient processes in vapor bubbles for a steplike increase in thermal load are presented.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 37, No. 6, pp. 1015–1020, December, 1979.     

Identification of unsteady boundary conditions in surface boiling of underheated liquids

The article presents a method and the results of determining the boundary conditions in surface boiling by the solution of the inverse heat-conduction problem with the use of the method of dynamic filtration.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 3, pp. 486–491, September, 1985.     

Critical heat flux in a boiling aqueous dispersion of nanoparticles

The effect of nanoparticles in an aqueous dispersion (nanofluid) on the critical heat flux (CHF) removed by boiling liquid from a heat-exchange surface has been studied. It is shown that a nanoparticles layer formed on the heated surface in the course of boiling possesses a hierarchical structure. Hydrophilic properties of this layer and its high permeability facilitating the supply of liquid to vapor bubbles lead to an increase in the CHF density.     

Heat exchange in film boiling of cryogenic liquids under natural convection conditions

Heat exchange is studied in stationary and nonstationary cooling of vertical cylinders by hydrogen and nitrogen. An empirical function generalizing the experimental results is presented.     

Heat transfer intensity at forced flow boiling of cryogenic liquids in tubes

A generalized correlation for heat transfer with forced flow boiling of cryogenic liquids (nitrogen, hydrogen and neon) in tubes is presented. The correlation describes, with a ± 35% accuracy, all known experimental data for vertical and horizontal channels (without stratified regimes) in the pressure range 0.9 – 22 bar, mass flow rates from 20 to 2200 kg m^?2 S^?1, and heat fluxes from 400 to 210 000 W m^?2. The boundary line between channels of a large and a small diameter has been established; a simple method of taking into account the higher heat transfer intensity in capillaries has been suggested.     

Molecular thermal conductivity of organic liquids

The molecular thermal conductivity of a number of organic liquids is measured using a nonstationary method in an optically thin layer.     

Predicting the thermal parameters of liquids

A three-constant equation of state has been used to describe the thermodynamics of the liquid phase for substances with various types of molecular interaction, and a method has been devised for forecasting the thermal parameters of normal and slightly polar liquids, which enables one to predict the density with a mean error of 0.5%.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 52, No. 3, pp. 409–414, March, 1987.     

Nucleate and film pool boiling heat transfer to saturated liquid helium

Pool boiling heat transfer from a square copper heating surface to liquid helium has been investigated experimentally. The study includes both nucleate and film boiling regimes, the measurements of maximum and minimum heat fluxes and superheats of the heating wall in the pressure region from 0.445 up to 0.98 P/P_c. The results are compared with the available experimental data and correlations.     

The mechanism of scale formation in the boiling of nonsaturated and saturated aqueous solutions

Various concepts on the mechanism of calcium-sulfate scale formation are considered. An especially formulated experimental investigation is used to demonstrate that the mechanism of scale formation on the boiling of saturated and nonsaturated solutions differs substantially.     

制冷剂饱和状态热力性质的计算

为了提高制冷剂饱和状态的热力特性简化计算公式的精度,提出新的简化计算模型,采用数值计算和分析的方法推导一些常用制冷剂饱和状态的热力特性的简化计算公式,验证提出的公式模型在一定范围内的可行性,并为制冷剂饱和状态热力性质参数的计算提供方便.     

Critical boiling heat transfer: special case of smooth exchange of bubble and film boiling regimes

The author presents results of an unconventional analysis of critical heat transfer interpreted as boundaries of a transition boiling region with a smooth exchange of bubble and film boiling regimes. A stepwise exchange of these boiling regimes, i.e., critical heat transfer in the textbook sense, is examined as a special case. The influence of various parameters on the boundaries and the transition boiling zone is demonstrated.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 59, No. 3, pp. 437–445, September, 1990.