Статті в журналах: "Boiling of a liquid"

1

Lee, T. Y. Tom, Mali Mahalingam, and Peter J. C. Normington. "Subcooled Pool Boiling Critical Heat Flux in Dielectric Liquid Mixtures." Journal of Electronic Packaging 115, no. 1 (March 1, 1993): 134–37. http://dx.doi.org/10.1115/1.2909294.

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The beneficial effect of using dielectric liquid mixture in reducing temperature overshoot in pool boiling has been studied by the authors (Normington et al., 1992). The current experimental work addresses the influence of mixtures of dielectric liquids on the critical heat flux (CHF) in pool boiling. Two families of dielectric liquids were evaluated: perfluorocarbon liquids and perfluoropolyether liquids. Each set of the family consisted of two liquids with boiling points ranging from 80°C−110°C. Both 100 percent of each liquid and mixtures of two liquids were tested. Video filming was used along with electronic data collection. The perfluoropolyether liquids showed an increase in CHF as more high boiling liquid was added to the mixture, while the perfluorocarbon liquids had a constant CHF for all mixtures.

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2

Michiyoshi, I. "Boiling Heat Transfer in Liquid Metals." Applied Mechanics Reviews 41, no. 3 (March 1, 1988): 129–49. http://dx.doi.org/10.1115/1.3151887.

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This article presents the state-of-the-art review of boiling heat transfer in various liquid metals paying attention to research papers published in the last 15 years. Particular emphasis is laid on the incipient boiling superheat, diagnosis of natural and forced convection boiling, nucleate pool boiling heat transfer in mercury, sodium, potassium, NaK, lithium, and so on at sub- and near atmospheric pressure, effect of liquid level on liquid metal boiling, subcooling effect due to hydrostatic head on liquid metal boiling, effect of magnetic field on liquid metal boiling, pool boiling crisis under various conditions and intermittent boiling of liquid metal, two-phase flow heat transfer, and natural and forced convection film boiling in saturated and subcooled liquid metals. In conclusion, there still remain some ambiguous and unsolved problems which are pointed out in this article. Further studies are of course required to clarify and solve them in future with both theoretical and experimental approaches.

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3

Chen, Tailian, and Suresh V. Garimella. "Effects of Dissolved Air on Subcooled Flow Boiling of a Dielectric Coolant in a Microchannel Heat Sink." Journal of Electronic Packaging 128, no. 4 (February 1, 2006): 398–404. http://dx.doi.org/10.1115/1.2351905.

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The effects of dissolved air in the dielectric liquid FC-77 on flow boiling in a microchannel heat sink containing ten parallel channels, each 500μm wide and 2.5mm deep, were experimentally investigated. Experiments were conducted before and after degassing, at three flow rates in the range of 30-50ml∕min. The dissolved air resulted in a significant reduction in wall temperature at which bubbles were first observed in the microchannels. Analysis of the results suggests that the bubbles observed initially in the undegassed liquid were most likely air bubbles. Once the boiling process is initiated, the wall temperature continues to increase for the undegassed liquid, whereas it remains relatively unchanged in the case of the degassed liquid. Prior to the inception of boiling in the degassed liquid, the heat transfer coefficients with the undegassed liquid were 300-500% higher than for degassed liquid, depending on the flow rate. The heat transfer coefficients for both cases reach similar values at high heat fluxes (>120kW∕m2) once the boiling process with the degassed liquid was well established. The boiling process induced a significant increase in pressure drop relative to single-phase flow; the pressure drop for undegassed liquid was measured to be higher than for degassed liquid once the boiling process became well established in both cases. Flow instabilities were induced by the boiling process, and the magnitude of the instability was quantified using the standard deviation of the measured pressure drop at a given heat flux. It was found that the magnitude of flow instability increased with increasing heat flux in both the undegassed and degassed liquids, with greater flow instability noted in the undegassed liquid.

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4

Vasil’ev, N. V., Yu A. Zeigarnik, K. A. Khodakov, S. N. Vavilov, and A. S. Nikishin. "Studying of the characteristics of a single bubble under subcooled liquid boiling." Journal of Physics: Conference Series 2088, no. 1 (November 1, 2021): 012048. http://dx.doi.org/10.1088/1742-6596/2088/1/012048.

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Abstract An experimental study of the characteristics of single (solitary) bubbles obtained by means of focused laser heating of the surface during the boiling of two subcooled liquids with significantly different properties: water and refrigerant R113 has been carried out. To obtain the most complete detailed information, the technique of synchronized high-speed video filming of the process in two mutually perpendicular planes with a frame rate of up to 150 kHz was used. It is shown that during the boiling of a subcooled liquid, the main mechanism of heat removal from the bubble dome into the surrounding liquid is an unsteady heat conductance. Differences in the behavior of solitary vapor bubbles in the case of boiling of two liquids (water and refrigerant R113) are shown.

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5

Wang, Qing Yu, Song Qing Lin, Liu Shan Yang, Zhi Zhen Huang, Man Man Zhou, and Yan Dong Ma. "Influence of Liquid Mass on Purificating Sugar from Candied Liquid of Preserved Fruits with Evaporation Method." Advanced Materials Research 356-360 (October 2011): 1105–8. http://dx.doi.org/10.4028/www.scientific.net/amr.356-360.1105.

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In order to observe the influence of liquid mass with evaporating purification from candied liquid of preserved fruits in the same boiling time, volume were obtained 35 g, 40 g, 45 g, 50 g, 55 g of candied liquid to evaporate. Boiling the solution for each time for 25 mins, the quality of each of four groups of parallel experiments was done to measure the candied liquid evaporation after sugar, the effects of different quality candied liquid evaporation effect. The results showed that in the same boiling time, the increase in quality with liquid, sugar becomes larger and larger; Candied liquid boiling temperature is about 99 °C, liquid in the different quality of candied sugar by evaporation and purification process need different times to boiling; In these experiments, candied sugar solution used was 60.8% of the percentage content.

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6

Fukusako, S., T. Komoriya, and N. Seki. "An Experimental Study of Transition and Film Boiling Heat Transfer in Liquid-Saturated Porous Bed." Journal of Heat Transfer 108, no. 1 (February 1, 1986): 117–24. http://dx.doi.org/10.1115/1.3246875.

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Experimental investigations of transition and film boiling in a liquid-saturated porous bed are reported. The porous bed contained in a vertical circular cylinder is made up of packed spherical beads whose diameters range from 1.0 to 16.5 mm, while the depth of the bed overlying the heating surface varies from 10 to 300 mm. Water and fluorocarbon refrigerants R-11 and R-113 are adopted as testing liquids. Special attention is focused on the effect of the diameter of spherical beads on boiling heat transfer in the transition boiling region. It is found that for the small bead diameters the steady boiling heat transfer rises monotonically with temperature from nucleate boiling through the film boiling region, without going through a local maximum.

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7

Dragunov, Y., M. Bykov, Y. Bezrukov, S. Alekseenko, N. Pribaturin, S. Lezhnin, and A. Sorokin. "ICONE15-10610 INVESTIGATION OF BOILING LIQUID FLOW THROUGH PIPELINE BREAK." Proceedings of the International Conference on Nuclear Engineering (ICONE) 2007.15 (2007): _ICONE1510. http://dx.doi.org/10.1299/jsmeicone.2007.15._icone1510_333.

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8

Li, Hong, Liu Shan Yang, Yan Dong Ma, Zhi Zhen Huang, Man Man Zhou, and Song Qing Lin. "Influence of Boiling Time on Purifying Sugar from Preserved Fruits Candied Liquid with Evaporation Method." Advanced Materials Research 356-360 (October 2011): 1097–100. http://dx.doi.org/10.4028/www.scientific.net/amr.356-360.1097.

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In order to observe the influences of liquid boiling time on purifying sugar from candied liquid with evaporation method, 50 g of candied liquid was weighed for evaporating experiments and control of the boiling time is 10 min, 20 min, 25 min, 30 min. In these experiments, 6 parallel experiments were done at each boiling time for observing the change of the candied liquid in different boiling time and determining the sweetness of candied liquid. The results show that: with the increase of boiling time, sugar content continue to decrease; Selected time for the purity of the purified sugar have a great impact.

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9

Moraru, V. N. "THE MECHANISM OF RAISING AND QUANTIFICATION OF SPECIFIC HEAT FLUX AT BOILING OF NANOFLUIDS IN FREE CONVECTION CONDITIONS." Energy Technologies & Resource Saving, no. 3 (March 20, 2017): 25–34. http://dx.doi.org/10.33070/etars.3.2017.03.

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The results of our work and a number of foreign studies indicate that the sharp increase in the heat transfer parameters (specific heat flux q and heat transfer coefficient _) at the boiling of nanofluids as compared to the base liquid (water) is due not only and not so much to the increase of the thermal conductivity of the nanofluids, but an intensification of the boiling process caused by a change in the state of the heating surface, its topological and chemical properties (porosity, roughness, wettability). The latter leads to a change in the internal characteristics of the boiling process and the average temperature of the superheated liquid layer. This circumstance makes it possible, on the basis of physical models of the liquids boiling and taking into account the parameters of the surface state (temperature, pressure) and properties of the coolant (the density and heat capacity of the liquid, the specific heat of vaporization and the heat capacity of the vapor), and also the internal characteristics of the boiling of liquids, to calculate the value of specific heat flux q. In this paper, the difference in the mechanisms of heat transfer during the boiling of single-phase (water) and two-phase nanofluids has been studied and a quantitative estimate of the q values for the boiling of the nanofluid is carried out based on the internal characteristics of the boiling process. The satisfactory agreement of the calculated values with the experimental data is a confirmation that the key factor in the growth of the heat transfer intensity at the boiling of nanofluids is indeed a change in the nature and microrelief of the heating surface. Bibl. 20, Fig. 9, Tab. 2.

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10

Zou, Jintao, Hongguang Zhang, Zhenjiang Guo, Yawei Liu, Jiachen Wei, Yan Huang, and Xianren Zhang. "Surface Nanobubbles Nucleate Liquid Boiling." Langmuir 34, no. 46 (November 2018): 14096–101. http://dx.doi.org/10.1021/acs.langmuir.8b03290.

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11

Nakoryakov, V. E., A. N. Tsoy, I. V. Mezentsev, and A. V. Meleshkin. "Explosive boiling of liquid nitrogen." Thermal Engineering 61, no. 13 (December 2014): 919–23. http://dx.doi.org/10.1134/s0040601514130060.

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12

Elias, Ezra, and P. L. Chambré. "Liquid superheat during nonequilibrium boiling." Heat and Mass Transfer 45, no. 5 (November 27, 2008): 659–62. http://dx.doi.org/10.1007/s00231-008-0467-4.

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13

Yagov, V. V. "Mechanism of transient liquid boiling." Journal of Engineering Physics and Thermophysics 64, no. 6 (June 1993): 596–605. http://dx.doi.org/10.1007/bf01089960.

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14

Chen, Si Ning. "Influences of Obstacles Installed in the Container on the Superheated Liquid Boiling." Advanced Materials Research 429 (January 2012): 62–66. http://dx.doi.org/10.4028/www.scientific.net/amr.429.62.

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During the accident mechanism investigation of Boiling Liquid Expanding Vapor Explosion (BLEVE), numerous dada shows that overheated liquid explosive boiling is the main reason and driving force to cause accidents. Research on the micro-process of overheated liquid instant boiling in BLEVE as well as the microscopic mechanism to influence this process development under different device conditions is favorable to seek the preventive and control measures for this accident. In this paper, regarding the mesh obstacle provided inside the storage tank, high-speed camera technology has been utilized to shoot the boiling process during continuous leakage of the storage tank, and the influence of the obstacle on the overheated liquid boiling has been tested and analyzed. It is found out that the boiling process of overheated liquid has been delayed. When the bubbles are rising, the growth process has been suppressed, after passing the obstacle, the movement speed and volume has been decreased, and the upward expansion speed of two-phase flow has also been decreased.

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15

IIDA, Yoshihiro, and Takeo TAKASHIMA. "A Study on Liquid-Liquid Leidenfrost Film Boiling." JSME international journal. Ser. 2, Fluids engineering, heat transfer, power, combustion, thermophysical properties 31, no. 4 (1988): 727–33. http://dx.doi.org/10.1299/jsmeb1988.31.4_727.

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16

Sakurai, A., M. Shiotsu, and K. Hata. "A General Correlation for Pool Film Boiling Heat Transfer From a Horizontal Cylinder to Subcooled Liquid: Part 1—A Theoretical Pool Film Boiling Heat Transfer Model Including Radiation Contributions and Its Analytical Solution." Journal of Heat Transfer 112, no. 2 (May 1, 1990): 430–40. http://dx.doi.org/10.1115/1.2910396.

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A rigorous numerical solution of a theoretical model based on laminar boundary layer theory for pool film boiling heat transfer from a horizontal cylinder including the contributions of liquid subcooling and radiation from the cylinder was obtained. The numerical solution predicted accurately the experimental results of pool film boiling heat transfer from a horizontal cylinder in water with high radiation emissivity for a wide range of liquid subcooling in the range of nondimensional cylinder diameters around 1.3, where the numerical solution was applicable to the pool film boiling heat transfer from a cylinder with negligible radiation emissivity. An approximate analytical solution for the theoretical model was also derived. It was given by the sum of the pool film boiling heat transfer coefficient if there were no radiation and the radiation heat transfer coefficient for parallel plates multiplied by a nondimensional radiation parameter similar to the expression for saturated pool film boiling given by Bromley. The approximate analytical solution agreed well with the rigorous numerical solution for various liquids of widely different physical properties under wide ranges of conditions.

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17

Avramenko, А., M. Kovetskaya, A. Tyrinov, and Yu Kovetska. "Characteristics of supercritical heat transfer during filmboiling of nanofluids on a vertical heated wall." Nuclear and Radiation Safety, no. 4(80) (December 3, 2018): 29–35. http://dx.doi.org/10.32918/nrs.2018.4(80).05.

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Nanofluid using for intensification of heat transfer during boiling are analyzed. The using boiling nanofluids for cooling high-temperature surfaces allows significantly intensify heat transfer process by increasing the heat transfer coefficient of a nanofluid in comparison with a pure liquid. The properties of nanoparticles, their concentration in the liquid, the underheating of the liquid to the saturation temperature have significant effect on the rate of heat transfer during boiling of the nanofluid. Increasing critical heat flux during boiling of nanofluids is associated with the formation of deposition layer of nanoparticles on heated surface, which contributes changing in the microcharacteristics of heat exchange surface. An increase in the critical heat flux during boiling of nanofluids is associated with the formation of a layer of deposition of nanoparticles on the surface, which contributes to a change in the microcharacteristics of the heat transfer of the surface. Mathematical model and results of calculation of film boiling characteristics of nanofluid on vertical heated wall are presented. It is shown that the greatest influence on the processes of heat and mass transfer during film boiling of the nanofluid is exerted by wall overheating, the ratio of temperature and Brownian diffusion and the concentration of nanoparticles in the liquid. The mathematical model does not take into account the effect changing structure of the heated surface on heat transfer processes but it allows to evaluate the effect of various thermophysical parameters on intensity of deposition of nanoparticles on heated wall. The obtained results allow to evaluate the effect of nanofluid physical properties on heat and mass transfer at cooling of high-temperature surfaces. The using nanofluids as cooling liquids for heat transfer equipment in the regime of supercritical heat transfer promotes an increase in heat transfer and accelerates the cooling process of high-temperature surfaces. Because of low thermal conductivity of vapor in comparison with the thermal conductivity of the liquid, an increase in the concentration of nanoparticles in the vapor contributes to greater growth in heat transfer in the case of supercritical heat transfer.

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18

Rozentsvaig, Alexander, and Cheslav Strashinskii. "Boiling in volume of low temperature droplets of dispersed phase of liquid emulsions." Thermal Science 21, no. 6 Part B (2017): 2981–92. http://dx.doi.org/10.2298/tsci151215286r.

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Mechanisms of droplets boiling in dispersed liquid-liquid systems differ significantly from more commonly studied and better understood mechanisms of vaporization in homogeneous fluids. For the analysis of boiling of liquid emulsions with low-temperature dispersed phase the theory of Labuntsov has been used, which was developed for boiling of homogeneous fluid near a solid wall. Model representations of more complex physical phenomena were substantiated using the similarity criteria, corresponding to the character of the heat exchange mechanisms with the dispersed droplets in the analogous conditions. A modified calculated dependence has been obtained for liquid emulsions with the low boiling dispersed phase. The results of the calculations are compared with the data of visual observations and experimental studies from the literature. It turned out that depending on the concentration of dis-persed phase heat transfer in emulsions is characterized by two regimes with different nucleate boiling mechanisms. Good agreement was indicated with measured data of heat flux at boiling of emulsions of water-in-oil type.

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19

Kawanami, Osamu, Kazuki Matsuhiro, Yasuhiko Hara, Itsuro Honda, and Naohisa Takagaki. "Liquid-liquid interfacial instability model for boiling refrigerant transition by pool boiling of immiscible mixtures." International Journal of Heat and Mass Transfer 146 (January 2020): 118826. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2019.118826.

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20

Sakurai, A., M. Shiotsu, and K. Hata. "A General Correlation for Pool Film Boiling Heat Transfer From a Horizontal Cylinder to Subcooled Liquid: Part 2—Experimental Data for Various Liquids and Its Correlation." Journal of Heat Transfer 112, no. 2 (May 1, 1990): 441–50. http://dx.doi.org/10.1115/1.2910397.

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Experimental data of pool film boiling heat transfer from horizontal cylinders in various liquids such as water, ethanol, isopropanol, Freon-113, Freon-11, liquid nitrogen, and liquid argon for wide ranges of system pressure, liquid subcooling, surface superheat and cylinder diameter are reported. These experimental data are compared with a rigorous numerical solution and an approximate analytical solution derived from a theoretical model based on laminar boundary layer theory for pool film boiling heat transfer from horizontal cylinders including the effects of liquid subcooling and radiation from the cylinder. A new correlation was developed by slightly modifying the approximate analytical solution to agree better with the experimental data. The values calculated from the correlation agree with the authors’ data within ± 10 percent, and also with other researchers’ data for various liquids including those with large radiation effects, though these other data were obtained mainly under saturated conditions at atmospheric pressure.

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21

Park, Jongdoc, Katsuya Fukuda, and Qiusheng Liu. "CHF Phenomena by Photographic Study of Boiling Behavior due to Transient Heat Inputs." Science and Technology of Nuclear Installations 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/248923.

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The transient boiling heat transfer characteristics in a pool of water and highly wetting liquids such as ethanol and FC-72 due to an exponentially increasing heat input of various rates were investigated using the 1.0 mm diameter experimental heater shaped in a horizontal cylinder for wide ranges of pressure and subcooling. The trend of critical heat flux (CHF) values in relation to the periods was divided into three groups. The CHF belonging to the 1st group with a longer period occurs with a fully developed nucleate boiling (FDNB) heat transfer process. For the 2nd group with shorter periods, the direct transition to film boiling from non boiling occurs as an explosive boiling. The direct boiling transition at the CHF from non-boiling regime to film boiling occurred without a heat flux increase. It was confirmed that the initial boiling behavior is significantly affected by the property and the wettability of the liquid. The photographic observations on the vapor bubble behavior during transitions to film boiling were performed using a high-speed video camera system.

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22

Hożejowska, Sylwia, Robert Kaniowski, and Mieczysùaw E. Poniewski. "Application of adjustment calculus to the Trefftz method for calculating temperature field of the boiling liquid flowing in a minichannel." International Journal of Numerical Methods for Heat & Fluid Flow 24, no. 4 (April 29, 2014): 811–24. http://dx.doi.org/10.1108/hff-01-2013-0022.

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Purpose – The purpose of this paper is to focus on the application of the Trefftz method to the calculation of the two-dimensional (2D) temperature field in the boiling refrigerant flow through an asymmetrically heated vertical minichannel with a rectangular cross-section. The considerations were limited to determining the temperature of the continuous phase – liquid for bubbly and bubbly-slug flow. The numerical solution found with the Trefftz methods was compared with the simplified solution. For nucleate boiling, heat transfer coefficient at the heating foil – liquid contact was determined. Design/methodology/approach – The Trefftz method was used to determine 2D temperature distributions for the glass pane, the heating foil and the boiling liquid. The temperature fields were approximated by the sum of the particular solution and the linear combination of suitable Trefftz functions. Coefficients of linear combination were computed using experimental data, including heating foil temperature measurements obtained with the liquid-crystal method and experimentally determined void fraction. The computations were based on the Trefftz method supplemented with the adjustment calculus. Findings – The way of solving direct and inverse problems of heat conduction in solid bodies (isolating glass, heating foil) and in liquids (boiling refrigerant flowing through the minichannel) was presented. For the first time, both 2D temperature fields for the heating foil and the boiling liquid were calculated while simultaneously using the Trefftz method. The known temperature values of the foil and liquid allowed the calculation of the heat transfer coefficient and the heat flux at the heating foil-liquid contact. Adjustment calculus implemented into the Trefftz method was used to smooth the measurement data and to reduce their errors. Practical implications – The approach proposed in the paper can be applied to determining 2D temperature field, heat flux and heat transfer coefficient in direct and inverse problems concerning two-phase flowing miniature compact heat exchangers. Originality/value – The paper presents a novel implementation of the Trefftz method to simultaneous solving an inverse problem in the heating foil and the contacting flowing liquid.

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23

Sarafraz, M. M., S. M. Peyghambarzadeh, and S. A. Alavi Fazel. "Enhancement of the pool boiling heat transfer coefficient using the gas injection into the water." Polish Journal of Chemical Technology 14, no. 4 (December 1, 2012): 100–109. http://dx.doi.org/10.2478/v10026-012-0110-5.

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Abstract In this paper, a new method for enhancing the pool boiling heat transfer coefficient of pure liquid, based on the gas injection through the liquids has been introduced. Hence, the effect of gas dissolved in a stagnant liquid on pool boiling heat transfer coefficient, nucleation site density, and bubble departure diameter has experimentally been investigated for different mole fractions of SO2 and various heat fluxes up to 114 kW/ m2. The presence of SO2 in captured vapor inside the bubbles, particularly around the heat transfer surface increases the pool boiling heat transfer coefficient. The available predicted correlations are unable to obtain the reasonable values for pool boiling heat transfer coefficient in this particular case. Therefore, to predict the pool boiling heat transfer coefficient accurately, a new modified correlation based on Stephan-Körner relation has been proposed. Also, during the experiments, it is found that nucleation site density is a strictly exponential function of heat flux. Accordingly, a new correlation has been obtained to predict the nucleation site density. The major application of the nucleation site density is in the estimating of mean bubble diameters as well as local agitation due to the rate of bubble frequency.

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24

Chang, K. H., and L. C. Witte. "Liquid-Solid Contact During Flow Film Boiling of Subcooled Freon-11." Journal of Heat Transfer 112, no. 2 (May 1, 1990): 465–71. http://dx.doi.org/10.1115/1.2910401.

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Liquid-solid contacts were measured for flow film boiling of subcooled Freon-11 over an electrically heated cylinder equipped with a surface microthermocouple probe. No systematic variation of the extent of liquid-solid contact with wall superheat, liquid subcooling, or velocity was detected. Only random small-scale contacts that contribute negligibly to overall heat transfer were detected when the surface was above the homogeneous nucleation temperature of the Freon-11. When large-scale contacts were detected, they led to an unexpected intermediate transition from local film boiling to local transition boiling. An explanation is proposed for these unexpected transitions. A comparison of analytical results that used experimentally determined liquid-solid contact parameters to experimental heat fluxes did not show good agreement. It was concluded that the available model for heat transfer accounting for liquid-solid contact is not adequate for flow film boiling.

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25

Surov, V. S. "A hyperbolic model of boiling liquid." Computational Continuum Mechanics 12, no. 2 (2019): 185–91. http://dx.doi.org/10.7242/1999-6691/2019.12.2.16.

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26

Shusser, M., and D. Weihs. "Explosive boiling of a liquid droplet." International Journal of Multiphase Flow 25, no. 8 (December 1999): 1561–73. http://dx.doi.org/10.1016/s0301-9322(98)00078-0.

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27

PARK, Jongdock, Katsuya FUKUDA, and Qiusheng LIU. "Pool Boiling CHF of Wetting Liquid." Proceedings of the JSME annual meeting 2004.3 (2004): 49–50. http://dx.doi.org/10.1299/jsmemecjo.2004.3.0_49.

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28

Sastri, S. R. S., Swati Mohanty, and K. K. Rao. "Liquid volume at normal boiling point." Canadian Journal of Chemical Engineering 74, no. 1 (February 1996): 170–72. http://dx.doi.org/10.1002/cjce.5450740122.

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29

Ivashnev, O. E. "Pressure fluctuations in boiling liquid flows." Fluid Dynamics 27, no. 2 (1992): 216–20. http://dx.doi.org/10.1007/bf01052088.

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30

Takayoshi, S., W. Kokuyama, and H. Fukuyama. "The boiling suppression of liquid nitrogen." Cryogenics 49, no. 5 (May 2009): 221–23. http://dx.doi.org/10.1016/j.cryogenics.2008.12.013.

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31

Birk, A. M., and M. H. Cunningham. "The boiling liquid expanding vapour explosion." Journal of Loss Prevention in the Process Industries 7, no. 6 (November 1994): 474–80. http://dx.doi.org/10.1016/0950-4230(94)80005-7.

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32

Surov, V. S. "A Hyperbolic Model of Boiling Liquid." Journal of Applied Mechanics and Technical Physics 61, no. 7 (December 2020): 1153–59. http://dx.doi.org/10.1134/s0021894420070160.

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33

Shvetsov, D. A., A. N. Pavlenko, A. E. Brester, and V. I. Zhukov. "A map of regimes of evaporation and boiling in the horizontal liquid layer on the modified surface." Journal of Physics: Conference Series 2039, no. 1 (October 1, 2021): 012033. http://dx.doi.org/10.1088/1742-6596/2039/1/012033.

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Abstract The paper presents the results of the study of the evaporation and boiling regimes in thin horizontal layers of liquid on a modified surface in a wide range of changes in the pressure and height of the liquid layer. Depending on the heat flux, pressure, and height of the liquid layer, the formation of various structures was observed. In this paper, maps of the evaporation and boiling regimes are obtained, which show the heat fluxes from the natural convection regime up to the boiling crisis, depending on the height of the liquid layer. The results are compared with the calculation dependencies.

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34

Kobasko, Nikolai Mykola. "Intense Quench Process in Slow Agitated Water Salt and Polymer Solutions." European Journal of Applied Physics 3, no. 3 (May 21, 2021): 6–12. http://dx.doi.org/10.24018/ejphysics.2021.3.3.76.

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In the paper it is shown that quenching in slow agitated water salt solution of optimal concentration and in low concentration of inverse solubility polymers is intensive quenching creating maximal temperature gradients at the beginning of cooling. The evidence to support such idea were collected by analyzing quenching process in liquid media where any film boiling process was completely absent. In this case, surface temperature at the beginning of cooling drops closely to saturations temperature of a liquid within the interval 1–2 seconds, independently on nature of water solution, and then during transient nucleate boiling process maintains at the level of boiling point of a liquid which is often called self–regulated thermal process. The computer modeling of such cooling processes provided Kondrat’ev numbered Kn which are strongly linear function of time. At the beginning of cooling Kondrat’ev number is almost equal to 1 while average Kondrat’ev number Kn≥0.8. According to US Patent, intensive quenching starts when Kn=0.8. Based on achieved results, it is possible to perform intensive quenching in slow agitated of low concentration water salt and polymer solutions, usually initiated by hydrodynamic emitters. Along with liquid agitation, emitters generate resonance wave effect which destroys film boiling processes making cooling very uniform and intensive. The proposed IQ process works perfectly when martensite starts temperature Ms>Ts. If saturation temperature Ts≥Ms, intensive austempering process via cold liquids can be successfully performed to replace slow cooling of molten salts and alkalis by intensive quenching in liquid media.

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35

Sorokin, A., Eu Ivanov, Ju Kuzina, N. Denisova, A. Nizovtsev, V. Privezentsev, and G. Sorokin. "EXPERIMENTAL AND COMPUTATIONAL STUDIES OF THE BOILING PROCESS OF LIQUID METAL DURING THE DEVELOPMENT OF AN ACCIDENT IN A FAST REACTOR: HEAT TRANSFER AND CIRCULATION STABILITY." PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. SERIES: NUCLEAR AND REACTOR CONSTANTS 2020, no. 2 (June 26, 2020): 150–72. http://dx.doi.org/10.55176/2414-1038-2020-2-150-172.

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Studies of the boiling of alkali metals show that, compared with boiling water, the process of boiling liquid metals has significant features. Cooling of a fuel assembly in accident conditions when accident protection is triggered and circulation pumps are switched off (ULOF) leads to the study of fuel elements cooling at reduced coolant flow rates or even tipping circulation in fuel assemblies. There is only limited data on the boiling of sodium in fuel assemblies in these regimes. The results of a series of experiments on heat transfer and stability of circulation during boiling of a sodiumpotassium alloy on single fuel assembly models and in a parallel fuel assembly system with natural coolant circulation performed at JSC “SSC RF - IPPE” are presented. The results of comparing the data of the calculated and experimental studies are presented. The influence of the surface roughness of the fuel rods on the heat transfer and flow regimes during boiling of a liquid metal in bundles is demonstrated. The results of experimental studies of heat transfer during boiling of sodium in natural and forced convection regimes in a fuel assembly model with a “sodium cavity” located above the reactor core intended to compensate for the positive sodium void reactivity effect in emergency situations with sodium boiling are also presented. It is shown that it is possible to provide continuous sodium cooling of fuel element simulators in fuel assemblies under these conditions. The results of the generalization of data on heat transfer during boiling of liquid metals in bundles and a cartogram of the regimes of two-phase flow during boiling of liquid metals in bundles are presented. The objectives of further research are discussed.

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36

Marsh, William J., and Issam Mudawar. "Sensible Heating and Boiling Incipience in Free-Falling Dielectric Liquid Films." Journal of Electronic Packaging 111, no. 1 (March 1, 1989): 46–53. http://dx.doi.org/10.1115/1.3226508.

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Controlling boiling incipience is of paramount importance for reliable operation of liquid-cooled microelectronic heat sources during power transients. This study focuses on heat transfer from a simulated multichip module to a falling film. Experiments have been performed to develop an understanding of the influence of surface tension and wetting characteristics on sensible heat transfer and boiling incipience in free-falling dielectric (FC-72) liquid films. The boiling results reveal that the vanishingly small contact angle of FC-72 precludes the application of correlations currently employed to predict incipience. Also, the temperature excursion commonly encountered upon boiling incipience in wetting fluids was nonexistent in all the experimental runs.

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37

Kapusta, Łukasz Jan, Jakub Bachanek, Changzhao Jiang, Jakub Piaszyk, Hongming Xu, and Mirosław Lech Wyszyński. "Liquid Propane Injection in Flash-Boiling Conditions." Energies 14, no. 19 (October 1, 2021): 6257. http://dx.doi.org/10.3390/en14196257.

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This study aimed to investigate the influence of flash-boiling conditions on liquid propane sprays formed by a multi-hole injector at various injection pressures. The focus was on spray structures, which were analysed qualitatively and quantitatively by means of spray-tip penetration and global spray angle. The effect of flash boiling was evaluated in terms of trends observed for subcooled conditions. Propane was injected by a commercial gasoline direct injector into a constant volume vessel filled with nitrogen at pressures from 0.1 MPa up to 6 MPa. The temperature of the injected liquid was kept constant. The evolution of the spray penetration was observed by a high-speed camera with a Schlieren set-up. The obtained results provided information on the spray evolution in both regimes, above and below the saturation pressure of the propane. Based on the experimental results, an attempt to calibrate a simulation model has been made. The main advantage of the study is that the effects of injection pressure on the formation of propane sprays were investigated for both subcooled and flash-boiling conditions. Moreover, the impact of the changing viscosity and surface tension was limited, as the temperature of the injected liquid was kept at the same level. The results showed that despite very different spray behaviours in the subcooled and flash-boiling regimes, leading to different spray structures and a spray collapse for strong flash boiling, the influence of injection pressure on propane sprays in terms of spray-tip penetration and spray angle is very similar for both conditions, subcooled and flash boiling. As for the numerical model, there were no single model settings to simulate the flashing sprays properly. Moreover, the spray collapse was not represented very well, making the simulation set-up more suitable for less superheated sprays.

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38

Zhang, Weizhong, Takashi Hibiki, and Kaichiro Mishima. "Correlation for Flow Boiling Heat Transfer at Low Liquid Reynolds Number in Small Diameter Channels." Journal of Heat Transfer 127, no. 11 (June 20, 2005): 1214–21. http://dx.doi.org/10.1115/1.2039105.

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In view of significance of a heat transfer correlation of flow boiling under the conditions of low liquid Reynolds number or liquid laminar flow, and very few correlations in principle suitable for such flow conditions, this study is aiming at developing a heat transfer correlation of flow boiling at low liquid Reynolds number for small diameter channels. The correlation is developed based on superimposition of two main flow boiling mechanisms, namely nucleate boiling and forced convection. In the correlation, two terms corresponding to nucleate boiling and forced convection are obtained from the pool boiling correlation by Forster and Zuber and the analytical annular flow model by Hewitt and Hall-Taylor, respectively. An extensive comparison with a collected database indicates that the developed correlation works satisfactorily with mean deviation and rms errors of 19.1% and 24.3%, respectively, under many experimental conditions such as different channel geometries (circular and rectangular) and flow orientations (vertical and horizontal) for some test fluids (water, R11, R12, and R113). A detailed discussion reveals that existing correlations for turbulent flow boiling such as Chen’s correlation, Schrock and Grossman’s correlation, and Dengler and Addoms’s correlation may be derived from a generalized form of the newly developed correlation.

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39

Wongsaroj, Wongsakorn, Hideharu Takahashi, Natee Thong-Un, and Hiroshige Kikura. "Ultrasonic Measurement for the Experimental Investigation of Velocity Distribution in Vapor-Liquid Boiling Bubbly Flow." International Journal of Engineering and Technology Innovation 12, no. 1 (December 7, 2021): 16–28. http://dx.doi.org/10.46604/ijeti.2021.8329.

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This study proposes an ultrasonic velocity profiler (UVP) with a single ultrasonic gas-liquid two-phase separation (SUTS) technique to measure the velocity distribution of vapor-liquid boiling bubbly flow. The proposed technique is capable of measuring the velocity of the vapor bubble and liquid separately in boiling conditions. To confirm the viability of the measurement technique, the experiment is conducted on vertical pipe flow apparatus. The ultrasonic transmission and effect of ultrasonic refraction through the pipe wall and water are investigated at ambient temperature until subcooled boiling temperature is reached. The velocity profile in the water at elevated temperature is measured to verify the ability of the technique in this application. The bubbly flow velocity distribution measurement in boiling conditions is then demonstrated. The results show that the proposed technique can effectively investigate the velocity of both phases under various fluid conditions in boiling bubbly flow.

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40

Kandlikar, S. G. "Heat Transfer Characteristics in Partial Boiling, Fully Developed Boiling, and Significant Void Flow Regions of Subcooled Flow Boiling." Journal of Heat Transfer 120, no. 2 (May 1, 1998): 395–401. http://dx.doi.org/10.1115/1.2824263.

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Subcooled flow boiling covers the region beginning from the location where the wall temperature exceeds the local liquid saturation temperature to the location where the thermodynamic quality reaches zero, corresponding to the saturated liquid state. Three locations in the subcooled flow have been identified by earlier investigators as the onset of nucleate boiling, the point of net vapor generation, and the location where x = 0 is attained from enthalpy balance equations. The heat transfer regions are identified as the single-phase heat transfer prior to ONB, partial boiling (PB), and fully developed boiling (FDB). A new region is identified here as the significant void flow (SVF) region. Available models for predicting the heat transfer coefficient in different regions are evaluated and new models are developed based on our current understanding. The results are compared with some of the experimental data available in the literature.

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41

Гурашкин, А. Л., А. А. Старостин та П. В. Скрипов. "Импульсная активация вскипания перегретой жидкости лазерным излучением". Письма в журнал технической физики 46, № 12 (2020): 47. http://dx.doi.org/10.21883/pjtf.2020.12.49529.18245.

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On the example of n-pentane superheated on 81 K with respect to the liquid-vapor equilibrium temperature, the possibility of local activation of liquid boiling-up by a laser pulse at the end of a single-mode fiber is shown. An activation threshold for the radiation intensity at the end of the fiber has been revealed. The activation threshold value depends on the state of the fiber end, and the boiling-up processes are likely to develop at the interface. Like a spontaneous boiling-up process, a stepwise propagating change in the refractive index of the liquid is observed in the course of activation. The conclusion is drawn about the uniformity of the recorded processes at spontaneous and activated boiling-up of n-pentane.

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42

Yao, Shouguang, and Zecheng Teng. "Effect of Nanofluids on Boiling Heat Transfer Performance." Applied Sciences 9, no. 14 (July 15, 2019): 2818. http://dx.doi.org/10.3390/app9142818.

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At present, there are many applications of nanofluids whose research results are fruitful. Nanofluids can enhance the critical heat flux, but the effect on boiling heat transfer performance still has disagreement. Base liquids with higher viscosity improve the boiling heat transfer performance of nanofluids. When the base liquid is a multicomponent solution, the relative movement between the different solutions enhances the microscopic movement of the nanoparticles due to the different evaporation order during the boiling process, so that the boiling heat transfer performance is enhanced. Compared with the thermal conductivity of the heated surface, the deposition of the low thermal conductivity nanoparticles reduces the heat dissipation rate of the heated surface and improves the wall superheat. Then the enhancement of the boiling heat transfer coefficient should be attributed to the thermal conductivity improvement of base fluid and the bubble disturbance resulted from the nanoparticle’s microscopic motion.

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43

Shiina, Koji, and Seiichirou Sakaguchi. "Boiling heat transfer characteristics in liquid-liquid direct contact parallel flow of immiscible liquids." Heat Transfer - Japanese Research 26, no. 8 (1997): 493–514. http://dx.doi.org/10.1002/(sici)1520-6556(1997)26:8<493::aid-htj1>3.0.co;2-r.

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44

Huang, L., and L. C. Witte. "An Experimental Investigation of the Effects of Subcooling and Velocity on Boiling of Freon-113." Journal of Heat Transfer 118, no. 2 (May 1, 1996): 436–41. http://dx.doi.org/10.1115/1.2825863.

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Boiling heat transfer correlations were obtained for the maximum and minimum heat fluxes. Relationships among qmin/qmax, Weber number, and liquid Jakob number were obtained. Compelling evidence was found to indicate that significant cooling of the wake and/or the forward stagnation line can be caused by large-scale liquid–solid contacts while other parts of the surface experienced film boiling with little or no contact in the transition-film boiling regime. A criterion for large-scale liquid-solid contacts was developed. Another purpose of this study was to investigate whether a stable transition of boiling exists, i.e., if the ratio of the minimum and maximum heat fluxes approaches unity as liquid subcooling and velocity are increased. Extensive data using Freon-113 were taken, covering a wide range of fluid velocities (1.5 to 6.9 m/s) and liquid subcooling (29 to 100°C) at pressures ranging from 122 to 509 kPa. Cylindrical electric resistance heaters of two diameters, 6.35 mm and 4.29 mm, and made of Hastelloy-C and titanium, respectively, were used. The maximum qmin/qmax achievable with the apparatus was 0.9.

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45

Sverchkov, A. M., and S. I. Sumskoy. "Recording of the Cavitation Phenomena when Modeling Flows in the Trunk Pipelines." Occupational Safety in Industry, no. 11 (November 2020): 7–14. http://dx.doi.org/10.24000/0409-2961-2020-11-7-14.

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In the article, it is proposed to use a numerical method based on the approach of S.K. Godunov to simulate boiling in a pipeline. The paper presents a statement of the real problem of modeling a water hammer, considering possible boiling of the transported liquid on a real object — an oil pipeline. When solving the problem, two variants of flow modeling when closing the valve installed at the end of the pipeline were carried out. In the first Наука и техника 14 Безопасность Труда в Промышленности • Occupational Safety in Industry • № 11'2020 • www.safety.ru case, the possibility of liquid boiling was not considered. In the second case, this opportunity was considered. The performed numerical simulation showed that in the pipeline in emergency situations, liquid columns can be formed, separated by the cavitation zones and oscillating in different phases, respectively, at the collapse of the cavitation zones, which serve as a kind of pressure dampers, the collisions of liquid columns occur, which can lead, depending on the ratio of velocities, to hydraulic shocks that occur not on the valves, but on the linear part of the pipeline (local hydraulic shocks). The waves from these collapses, interacting with each other, create the new pressure peaks that do not coincide with the pattern of simple wave circulation, which are predicted in the simulations that do not consider possible liquid boiling. As a resul t, the pressures reached in the pipeline during fluid hammer is significantly different from what it would be in the absence of boiling. When boiling is considered, the maximum reached pressures are 40 % higher. Moreover, this excess is repeated. The detailed analysis of the pressure profile in the pipeline is given in the article. Based on the results of solving this problem, it is concluded that when modeling pre–emergency and emergency situations in the pipeline, it is necessary to consider the process of possible liquid boiling, since sometimes, as in the presented case, the values of the pressure surges can be higher than the values of the pressure surges in the liquid without considering boiling, which increases the likelihood of emergency depressurization.

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46

Вогман, Леонид Петрович, Станислав Гургенович Габриэлян, and Наталья Валентиновна Кондратюк. "EXPERIMENTAL STUDIES OF THE RELATIONSHIP BETWEEN THE BOILING TEMPERATURE AND THE FLASH TEMPERATURE OF MIXED HYDROCARBON FUELS." Актуальные вопросы пожарной безопасности, no. 2(8) (July 1, 2021): 35–40. http://dx.doi.org/10.37657/vniipo.avpb.2021.40.22.005.

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В работе экспериментально показано, что по мере испарения смесевой горючей жидкости при одновременном повышении плотности и снижении упругости пара в многокомпонентных взаиморастворимых композициях температура кипения повышается. В этом случае и температура вспышки смесевой горючей жидкости также будет повышаться. Так, при проливах горючих жидкостей происходит довольно быстрое обеднение легкими фракциями, упругость пара при заданной температуре существенно снижается, а температуры кипения и вспышки, соответственно, повышаются. Полученные в работе зависимости температур кипения и вспышки испытанных смесевых горючих жидкостей характерны и для других различных многокомпонентных жидких композиций. Эти зависимости могут учитываться при разработке планов предотвращения и ликвидации аварий в случае их проливов. Based on the experiments it is shown that as the flammable liquid mixtures evaporate, while increasing density and decreasing vapor tension in multicomponent compositions-soluble, the boiling temperature increases. In this case, the flash point of the mixed combustible liquid will also increase. Thus, in the case of spills of flammable liquids there is a fairly rapid depletion of light fractions, the vapor tension at a given temperature reduces significantly, and the boiling and flash temperatures increase accordingly. The dependences of the boiling and flash temperatures of the tested mixed combustible liquids obtained in this work are also typical for other various multicomponent liquid compositions. These dependencies can be taken into account when developing plans for the prevention and elimination of emergencies caused by their spills.

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47

Shin, Hyun-Ho, and Woong-Sup Yoon. "Non-Equilibrium Molecular Dynamics Simulation of Nanojet Injection with Adaptive-Spatial Decomposition Parallel Algorithm." Journal of Nanoscience and Nanotechnology 8, no. 7 (July 1, 2008): 3661–73. http://dx.doi.org/10.1166/jnn.2008.18332.

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An Adaptive-Spatial Decomposition parallel algorithm was developed to increase computation efficiency for molecular dynamics simulations of nano-fluids. Injection of a liquid argon jet with a scale of 17.6 molecular diameters was investigated. A solid annular platinum injector was also solved simultaneously with the liquid injectant by adopting a solid modeling technique which incorporates phantom atoms. The viscous heat was naturally discharged through the solids so the liquid boiling problem was avoided with no separate use of temperature controlling methods. Parametric investigations of injection speed, wall temperature, and injector length were made. A sudden pressure drop at the orifice exit causes flash boiling of the liquid departing the nozzle exit with strong evaporation on the surface of the liquids, while rendering a slender jet. The elevation of the injection speed and the wall temperature causes an activation of the surface evaporation concurrent with reduction in the jet breakup length and the drop size.

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48

Serdyukov, Vladimir, Anton Surtaev, and Oleg Volodin. "Investigation of the Dynamics of Nucleate Boiling in Subcooled Falling Liquid Films." Siberian Journal of Physics 9, no. 2 (June 1, 2014): 145–55. http://dx.doi.org/10.54362/1818-7919-2014-9-2-145-155.

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This paper deals with the features of nucleation dynamics at boiling in falling water films at different subcooling, Reynolds number and heat fluxes. With the use of high-speed infrared and digital video the local parameters of nucleate boiling in falling liquid films such as: bubbles’ diameter before condensation, frequency of nucleation and temperature of onset of bubble appearance were received. Analysis of the experimental data showed that bubbles’ diameter before condensation has strong dependence on initial temperature and increases with the rise of heat flux. The main influence on nucleation frequency has the variation of heat flux density. At the same time the experimental data on nucleation frequency in falling water films are close to the frequency of nucleation at pool boiling. To identify the main features the comparison of received data on the local characteristics at boiling in subcooled falling liquid film with existing models for pool boiling was made

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49

Price, H. W., S. A. Klein, and W. A. Beckman. "Analysis of Boiling Flat-Plate Collectors." Journal of Solar Energy Engineering 108, no. 2 (May 1, 1986): 150–57. http://dx.doi.org/10.1115/1.3268083.

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A detailed model for use with TRNSYS, capable of modelling a wide range of boiling collector types, was used to analyze boiling flat-plate collector systems. This model can account for a subcooled liquid entering the collector, heat losses in the vapor and the liquid return line, pressure drops due to friction in the collector and piping, and pressure drops due to the hydrostatic head of the fluid. The model has been used to determine the yearly performance of boiling flat-plate solar collector systems. A simplified approach was also developed which can be used with the f-Chart method to predict yearly performance of boiling flat-plate collector systems.

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50

Sajjad, Uzair, Imtiyaz Hussain, Muhammad Sultan, Sadaf Mehdi, Chi-Chuan Wang, Kashif Rasool, Sayed M. Saleh, Ashraf Y. Elnaggar, and Enas E. Hussein. "Determining the Factors Affecting the Boiling Heat Transfer Coefficient of Sintered Coated Porous Surfaces." Sustainability 13, no. 22 (November 16, 2021): 12631. http://dx.doi.org/10.3390/su132212631.

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The boiling heat transfer performance of porous surfaces greatly depends on the morphological parameters, liquid thermophysical properties, and pool boiling conditions. Hence, to develop a predictive model valid for diverse working fluids, it is necessary to incorporate the effects of the most influential parameters into the architecture of the model. In this regard, two Bayesian optimization algorithms including Gaussian process regression (GPR) and gradient boosting regression trees (GBRT) are used for tuning the hyper-parameters (number of input and dense nodes, number of dense layers, activation function, batch size, Adam decay, and learning rate) of the deep neural network. The optimized model is then employed to perform sensitivity analysis for finding the most influential parameters in the boiling heat transfer assessment of sintered coated porous surfaces on copper substrate subjected to a variety of high- and low-wetting working fluids, including water, dielectric fluids, and refrigerants, under saturated pool boiling conditions and different surface inclination angles of the heater surface. The model with all the surface morphological features, liquid thermophysical properties, and pool boiling testing parameters demonstrates the highest correlation coefficient, R2 = 0.985, for HTC prediction. The superheated wall is noted to have the maximum effect on the predictive accuracy of the boiling heat transfer coefficient. For example, if the wall superheat is dropped from the modeling parameters, the lowest prediction of R2 (0.893) is achieved. The surface morphological features show relatively less influence compared to the liquid thermophysical properties. The proposed methodology is effective in determining the highly influencing surface and liquid parameters for the boiling heat transfer assessment of porous surfaces.

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