Journal articles: 'Nucleate boiling'

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Dhillon, Navdeep S., Dilipkumar Choudhary, Jayden Maree, Victor Inhelder, and Jazmin Guadarrama. "Controlled generation of a vapor bubble representative of nucleate boiling conditions using transient focused laser heating." Journal of Applied Physics 133, no. 2 (January 14, 2023): 024702. http://dx.doi.org/10.1063/5.0134203.

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Nucleate boiling is a phenomenon of significant importance in a broad range of industries. Increasing boiling performance parameters could lead to more efficient power plants and better electronics thermal management. However, difficulties associated with studying this extremely complex phenomenon have prevented a meaningful progress in the area of boiling heat transfer enhancement. In this paper, we implement a laser-based controlled bubble generation technique to enable accurate phenomenological studies of the boiling process. We present details of the transient focused-laser heating mechanism used to nucleate a microscale vapor embryo on the boiling surface. We present high-speed optical imaging data showing how this vapor embryo grows into a bubble using electrically applied background heat flux. Unlike the currently available artificial bubble generation approaches, which either generate unphysical bubbles or are extremely difficult to implement, we show that the laser-nucleated controlled single bubble demonstrates bubble ebullition characteristics closely representative of naturally occurring bubbles in nucleate pool boiling.

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Sun, Tao, Weizhong Li, and Bo Dong. "Numerical simulation of vapor bubble growth on a vertical superheated wall using lattice Boltzmann method." International Journal of Numerical Methods for Heat & Fluid Flow 25, no. 5 (June 1, 2015): 1214–30. http://dx.doi.org/10.1108/hff-08-2013-0263.

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Purpose – The purpose of this paper is to test the feasibility of lattice Boltzmann method (LBM) for numerical simulation of nucleate boiling and transition boiling. In addition, the processes of nucleate and transition boiling on vertical wall are simulated. The heat transfer mechanism is discussed based on the evolution of temperature field. Design/methodology/approach – In this paper, nucleate boiling and transition boiling are numerically investigated by LBM. A lattice Boltzmann (LB) multiphase model combining with a LB thermal model is used to predict the phase-change process. Findings – Numerical results are in good agreement with existing experimental results. Numerical results confirm the feasibility of the hybrid LBM for direct simulations of nucleate and transition boiling. The data exhibit correct parametric dependencies of bubble departure diameter compared with experimental correlation and relevant references. Research limitations/implications – All the simulations are performed in two-dimensions in this paper. In the future work, the boiling process will be simulated in three-dimensional. Practical implications – This study demonstrated a potential model that can be applied to the investigation of phase change heat transfer, which is one of the effective techniques for enhance the heat transfer in engineering. The numerical results can be considered as a basic work or a reference for generalizing LB method in the practical application about nucleate boiling and transition boiling. Originality/value – The hybrid LBM is first used for simulation of nucleate and transition boiling on vertical surface. Heat transfer mechanism during boiling is discussed based on the numerical results.

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Katagiri, Masanori, Minoru Maeda, and Yoshiko Fujii. "Visualization of nucleate boiling." Physica B: Condensed Matter 329-333 (May 2003): 120–21. http://dx.doi.org/10.1016/s0921-4526(02)01916-6.

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Liu, Dong, Poh-Seng Lee, and Suresh V. Garimella. "Nucleate Boiling in Microchannels." Journal of Heat Transfer 127, no. 8 (August 1, 2005): 803. http://dx.doi.org/10.1115/1.2033487.

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Ma, C. F., and A. E. Bergles. "Jet impingement nucleate boiling." International Journal of Heat and Mass Transfer 29, no. 8 (August 1986): 1095–101. http://dx.doi.org/10.1016/0017-9310(86)90140-7.

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6

Cooper, P. "EHD Enhancement of Nucleate Boiling." Journal of Heat Transfer 112, no. 2 (May 1, 1990): 458–64. http://dx.doi.org/10.1115/1.2910400.

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This paper describes: (a) an experimental investigation into the effect of an electric field applied to pool boiling of Freon (R114) on a finned tube and (b) a theoretical model of electrically enhanced nucleate boiling applicable to simple surfaces only. Experimental results have shown electrohydrodynamic (EHD) enhancement of heat transfer to be manifest in two ways: (i) elimination of boiling hysteresis, (ii) augmentation of nucleate boiling heat transfer coefficients by up to an order of magnitude. These effects were also observed in electrically enhanced boiling of Freon/oil mixtures. A new analytical model is described whereby EHD nucleate boiling data from previous studies (employing simple apparatus comprising heated wires with concentric cylinder electrodes) have been correlated for the first time using the concept of an electrical influence number. This dimensionless parameter is based upon the relationship between applied electric field intensity and changes in bubble departure diameter at a heat transfer surface.

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Rainey, K. N., S. M. You, and S. Lee. "Effect of Pressure, Subcooling, and Dissolved Gas on Pool Boiling Heat Transfer From Microporous Surfaces in FC-72." Journal of Heat Transfer 125, no. 1 (January 29, 2003): 75–83. http://dx.doi.org/10.1115/1.1527890.

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The present research is an experimental study of the effects of pressure, subcooling, and non-condensable gas (air) on the pool nucleate boiling heat transfer performance of a microporous enhanced and a plain (machine-roughened) reference surface. The test surfaces, 1-cm2 flat copper blocks in the horizontal, upward facing orientation, were immersed in FC-72. The test conditions included an absolute pressure range of 30–150 kPa, a liquid subcooling range of 0 (saturation) to 50 K, and both gas-saturated and pure subcooling conditions. Effects of these parameters on nucleate boiling and critical heat flux (CHF) were investigated. Results showed that, in general, the effects of pressure and subcooling on both nucleate boiling and CHF were consistent with the prevailing trends in the literature. For the present heater geometry, the effects of dissolved gas on the boiling performance were generally small, however, as the dissolved gas content increased (through either increased pressure or subcooling) more of the nucleate boiling curve was affected (enhanced). The enhancement of CHF from increased liquid subcooling was greater for the microporous surface than the plain surface. Correlations for both nucleate boiling and CHF were also presented.

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Okawa, Tomio, Koki Nakano, and Yutaro Umehara. "Variations of nanoparticle layer properties during nucleate pool boiling." Journal of Physics: Conference Series 2116, no. 1 (November 1, 2021): 012002. http://dx.doi.org/10.1088/1742-6596/2116/1/012002.

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Abstract The nanoparticle layer detachment during nucleate pool boiling and its influences on heat transfer surface properties were explored experimentally. The material of the heat transfer surface was copper and the nanoparticle layer was formed on the heat transfer surface by nucleate boiling in the water-based TiO2 nanofluid. It was found that the detachment of the nanoparticle layer during nucleate boiling in pure water is significant. In the present experiment, more than half of nanoparticles deposited on the heated surface were detached before the CHF condition was reached. The thickness and roughness decreased accordingly. However, the wettability and wickability that are the influential parameters on the CHF value were maintained even after the occurrence of nanoparticle layer detachment and deteriorated only after the CHF condition was reached. It is therefore considered that the onset of CHF brings qualitative change to the capillary suction performance of the layer of nanoparticles. In exploring the effect of the nanoparticle layer properties on the nucleate boiling heat transfer, sufficient attention should be paid to the variation of the nanoparticle layer properties during nucleate boiling.

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Heindel, T. J., S. Ramadhyani, and F. P. Incropera. "Liquid Immersion Cooling of a Longitudinal Array of Discrete Heat Sources in Protruding Substrates: II—Forced Convection Boiling." Journal of Electronic Packaging 114, no. 1 (March 1, 1992): 63–70. http://dx.doi.org/10.1115/1.2905443.

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Forced convection boiling experiments have been performed for an in-line 1 x 10 array of discrete heat sources, flush mounted to protruding substrates located on the bottom wall of a horizontal flow channel. FC-72, a dielectric fluorocarbon liquid, was used as the heat transfer fluid, and the experiments covered a range of flow velocities, degrees of fluid subcooling, and channel heights. The maximum heater-to-heater surface temperature variation was less than 2.5°C and was insensitive to channel height under conditions of fully developed nucleate boiling. Although the fluid velocity influenced the heat flux for partially developed nucleate boiling, its influence was muted for fully developed nucleate boiling. The heat flux associated with a departure from nucleate boiling increased with increasing velocity, subcooling, and channel height; however, the effect of channel height was only significant when all of the upstream heaters were energized.

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Jing, Qi, and QingGuo Luo. "Experimental study on the correlation of subcooled boiling flow in horizontal tubes." Thermal Science, no. 00 (2020): 339. http://dx.doi.org/10.2298/tsci200801339j.

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Subcooled boiling is the most effective form of heat exchange in the water jacket of the cylinder head. Chen's model is the most widely used correlation for predicting boiling heat transfer, but the selection of the correlation for the nucleate boiling is controversial. The work of this paper is to simulate the heat transfer process in the water jacket of the cylinder head with a horizontal rectangular channel that is heated on one side. Using the coolant flow velocity, inlet temperature and system pressure as variables, the heat flux and heat transfer coefficient were obtained. The results show that the increase of the coolant flow velocity can effectively promote the convection heat transfer, and the change of inlet temperature and system pressure will affect the occurrence of nucleate boiling. However, the Chen?s model predictions doesn?t fit well with the experimental data. Four nucleate boiling correlations were selected to replace Chen's model nucleate boiling correlation. The correlation proposed by Pioro coincides best with the experimental data. The mean error after correction is 18.2%.

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Abyzov, Oleg, Yuri Galyshev, and Andrey Metelev. "Implementation of the mechanistic wall boiling model in IC engine cooling gallery simulation." MATEC Web of Conferences 245 (2018): 09006. http://dx.doi.org/10.1051/matecconf/201824509006.

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The ever increasing power rates of modern IC engines pose a great challenge for maintaining the optimal temperature conditions. The current trend in the thermal management of IC engines is to utilize the limited and controlled nucleate boiling to achieve higher heat transfer rates. The modern CFD instrumentation offers a wide range of methods for predicting nucleate and film boiling. Of the available models the mechanistic RPI wall boiling model is selected in present paper in the cojuntion with the Eulerian multiphase model available in ANSYS Fluent solver to simulate subcooled nucleate boiling in engine cooling jacket.Results obtained from the simulation of boiling flow in cooling passages is then compared with the experimental data from author’s previous work and show a decent agreement.

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Kandlikar, S. G. "A Model for Correlating Flow Boiling Heat Transfer in Augmented Tubes and Compact Evaporators." Journal of Heat Transfer 113, no. 4 (November 1, 1991): 966–72. http://dx.doi.org/10.1115/1.2911229.

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The additive model for the convective and nucleate boiling components originally suggested by Bergles and Rohsenow (1964) for subcooled and low-quality regions was employed in the Kandlikar correlation (1990a) for flow boiling in smooth tubes. It is now extended to augmented tubes and compact evaporators. Two separate factors are introduced in the convective boiling and the nucleate boiling terms to account for the augmentation effects due to the respective mechanisms. The fin efficiency effects in the compact evaporator geometry are included through a reduction in the nucleate boiling component over the fins due to a lower fin surface temperature. The agreement between the model predictions and the data reported in the literature is within the uncertainty bounds of the experimental measurements.

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A.A, Levin. "The pulsating nature of bubble boiling of subcooled water flow during cooling of a metal heater." E3S Web of Conferences 321 (2021): 01013. http://dx.doi.org/10.1051/e3sconf/202132101013.

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This paper presents the results of an experimental study of the subcooled water flow boiling on the surface of a metal rod 12 mm in diameter. As a result of the rapid heat release that occurs when an electric current is pulsed through a metal heater, the latter reaches certain temperature levels above the saturation temperature of water at the corresponding pressure (p = 0.17 MPa). In a system formed by a cold liquid and a heated solid body, the process of intense heat exchange begins, the cooling rate of the metal in which reaches its maximum when the nucleate boiling is realized. Interest in such scenarios is remaining high and is caused by the need for quantitative prediction of the characteristics of nucleate boiling and the existence boundaries of this boiling mode. As well-known, nucleate boiling is limited from above by the onset of film boiling and from below by the required surface temperature for which a significant number of nucleation centers are activated. The pressure waves arising during film boiling have a significant amplitude, as a result of which special conditions of interphase interactions may occur. The results of the study showed that self-oscillating pressure pulsations may occur which is associated with the nucleate boiling in an annular channel.

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Lin, W. W., and D. J. Lee. "Relative Stability Between Nucleate and Film Boiling on a Nonuniformly Heated Plate Surface." Journal of Heat Transfer 119, no. 2 (May 1, 1997): 326–31. http://dx.doi.org/10.1115/1.2824227.

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Flow boiling of methanol over a nonuniform, indirect conduction heating surface is investigated experimentally. An axial (discrete) heat flux distribution corresponding to a neutral stability region where nucleate and film boiling can coexist steadily is identified. Below such a heat flux distribution, nucleate boiling mode is more stable. Above this distribution, film boiling mode becomes more stable. We had employed an equal-area criterion for interpreting the heat flux and wall superheat relationship. Analogy between the wire boiling system is proposed. The differences between average and real transition boiling curves are discussed as well.

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Abyzov, O. V., Yu V. Galyshev, and A. K. Ivanov. "Experimental Investigation of Two-Phase Heat Transfer in a Simulated Cooling Duct of a Piston Engine Cylinder Head." Herald of the Bauman Moscow State Technical University. Series Mechanical Engineering, no. 4 (133) (August 2020): 4–15. http://dx.doi.org/10.18698/0236-3941-2020-4-4-15.

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Liquid cooling of cylinder and piston parts in highly boosted internal combustion engines is generally accompanied by local phase transition phenomena, such as surface nucleate boiling. The heat transfer coefficient of nucleate boiling is several times higher than that of single-phase convection. In order to efficiently exploit the thermal effect of nucleate boiling in cooling systems, simultaneously preventing emergency supercritical modes, a deeper understanding of boiling physics based on full-scale experiments is required. We conducted experimental investigation of heat transfer in a simulated cooling duct of a piston engine cylinder head, using a bespoke motor-free installation. We studied the effects of velocity, flow character and coolant type on the heat transfer, accounting for the presence of congestion regions. Over the course of the experiment, we simulated thermal conditions characteristic of different heat transfer types: single-phase convection, nucleate boiling, the onset of boiling crisis. We used the experimental data to plot the coolant heat flow density as a function of wall temperature for different measuring points situated inside the stream and the turbulent flow regions (congestion regions). We show that the mature nucleate boiling mode is the most favourable in terms of how uniform the temperature field within a part is. The experimental data obtained during the investigation may be used to verify mathematical simulations in the two-phase heat transfer theory, provided the data have been appropriately processed

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Zhukov, Vladimir I., and Aleksandr N. Pavlenko. "Symmetry of Structures under Two-Dimensional Instability in a Finite-Height Horizontal Layer of Boiling Liquid." Symmetry 15, no. 9 (September 20, 2023): 1792. http://dx.doi.org/10.3390/sym15091792.

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The two-dimensional instability of a horizontal layer of boiling liquid with a finite height was experimentally studied. In this layer, “vapor columns” rose at the corners of a square rectangular grid, and the symmetry of “vapor column” location on the heating surface was considered. The model adopts an approach to the boiling crisis from the side of both developed nucleate boiling and transitional boiling (the Zuber problem). When dealing with developed nucleate boiling, the layer of boiling liquid is considered in calculations as an isotropic homogeneous system (foam). It is shown how the conditions on the heating surface (capillary-porous coating) affect the external hydrodynamics of the liquid layer and, ultimately, the value of the critical heat flux. The calculation ratio obtained by approaching the boiling crisis from the side of developed nucleate boiling takes into account the dependence of the critical heat flux on the void fraction of the boiling liquid layer. A new solution to the boiling crisis problem is proposed when approaching the crisis from the side of transitional boiling (the Zuber problem). This new solution eliminates some shortcomings of the classical problem (in particular, the void fraction of the layer corresponds to the experiments).

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Cui, Qiang, Sanjeev Chandra, and Susan McCahan. "The Effect of Dissolving Salts in Water Sprays Used for Quenching a Hot Surface: Part 2—Spray Cooling." Journal of Heat Transfer 125, no. 2 (March 21, 2003): 333–38. http://dx.doi.org/10.1115/1.1532011.

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The effect of adding one of three salts (NaCl, Na2SO4 or MgSO4) to water sprayed on a hot surface was studied experimentally. A copper test surface was heated to 240°C and quenched with a water spray. The variation of surface temperature during cooling was recorded, and the surface heat flux calculated from these measurements. Surface heat flux during cooling with pure water sprays was compared with that obtained using salt solutions. Dissolved NaCl or Na2SO4 increased nucleate boiling heat transfer, but had little effect on transition boiling during spray cooling. MgSO4 increased both nucleate and transition boiling heat flux. Enhanced nucleate boiling was attributed to foaming in the liquid film generated by the dissolved salts. MgSO4 produced the largest increase in nucleate boiling heat transfer, Na2SO4 somewhat less and NaCl the least. A concentration of 0.2 mol/l of MgSO4 produced the greatest heat flux enhancement; higher salt concentrations did not result in further improvements. During transition boiling particles of MgSO4 adhered to the heated surface, raising surface roughness and increasing heat transfer. Addition of MgSO4 reduced the time required to cool a hot surface from 240°C to 120°C by an order of magnitude.

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Samant, K. R., and T. W. Simon. "Heat Transfer From a Small Heated Region to R-113 and FC-72." Journal of Heat Transfer 111, no. 4 (November 1, 1989): 1053–59. http://dx.doi.org/10.1115/1.3250767.

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An experimental investigation of heat transfer from a small heated patch to a subcooled, fully developed turbulent flow is conducted. The test patch, approximately 0.25 mm long and 2.0 mm wide, is located on the floor of a small rectangular channel through which a coolant (R-113 or FC-72) is circulated. A thin film of Nichrome deposited on a quartz substrate serves as an integrated heater element and resistance thermometer. The maximum achievable heat flux with R-113, limited by the thermal decomposition temperature of the fluid, is 2.04 MW/m2 at a bulk velocity of 1.8 m/s and a high wall superheat of 80° C. The results obtained with FC-72 show large temperature excursions at the onset of nucleate boiling and a boiling hysteresis near the onset of nucleate boiling. These effects decrease with increasing velocity and/or subcooling. The heat flux at departure from nucleate boiling increases with increasing velocity and/or subcooling. A maximum heat flux of 4.26 MW/m2 at departure from nucleate boiling is observed.

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Solodov, A. P. "Differential model of nucleate boiling." High Temperature 45, no. 2 (April 2007): 196–203. http://dx.doi.org/10.1134/s0018151x07020095.

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Kolev, Nikolay Ivanov. "To the nucleate boiling theory." Nuclear Engineering and Design 239, no. 1 (January 2009): 187–92. http://dx.doi.org/10.1016/j.nucengdes.2008.04.015.

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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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Aksel'rud, G. A., Ya M. Gumnitskii, and S. Mallik. "Investigation of chemical nucleate boiling." Journal of Engineering Physics 52, no. 2 (February 1987): 147–50. http://dx.doi.org/10.1007/bf00870752.

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Misyura, S. Ya. "Nucleate boiling in bidistillate droplets." International Journal of Heat and Mass Transfer 71 (April 2014): 197–205. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2013.12.013.

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Davidy, Alon. "CFD Simulation of Forced Recirculating Fired Heated Reboilers." Processes 8, no. 2 (January 22, 2020): 145. http://dx.doi.org/10.3390/pr8020145.

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An advanced algorithm has been developed in order to analyze the performance of re-boiling process of crude oil flowing inside reboilers tubes. The proposed model is composed from Heptane fire heater and a tube array. The heat flux produced from burner is transferred to the crude oil flowing inside the tube. The computational model is composed of two phases—Simulation of fire by using Fire Dynamics Simulator software (FDS) version 5.0 and then a nucleate boiling computation of the crude oil. FDS code is formulated based on CFD (Computational Fluid Dynamics) of fire heater. The thermo-physical properties (such as: thermal conductivity, heat capacity, surface tension, viscosity) of the crude oil were estimated by using empirical correlations. The thermal heat transfer to evaporating two-phase crude oil mixture occur by bubble generation at the wall (nucleate boiling) has been calculated by using Chen correlation. It has been assumed that the overall convective heat transfer coefficient is composed from the nucleate boiling convective coefficient and the forced turbulent convective coefficient. The former is calculated by Forster Zuber empirical equation. The latter is computed from the Dittus-Boelter relationship. In order to validate the nucleate boiling heat transfer coefficient, a comparison has been performed to nucleate boiling convective coefficient obtained by Mostinski equation. The relative error between the nucleate boiling convective heat-transfer coefficients is 10.5%. The FDS numerical solution has been carried out by using Large Eddy Simulation (LES) method. This work has been further extended to include also the structural integrity aspects of the reboiler metal pipe by using COMSOL Multiphysics software. It was found out, that the calculated stress is less than the ultimate tensile strength of the AISI 310 Steel alloy.

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Ungar, E. K., and R. Eichhorn. "Transition Boiling Curves in Saturated Pool Boiling From Horizontal Cylinders." Journal of Heat Transfer 118, no. 3 (August 1, 1996): 654–61. http://dx.doi.org/10.1115/1.2822682.

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Pool boiling heat flux versus wall superheat boiling curves were obtained for horizontal 3.18-mm-dia thin-walled brass tubes heated by an internal high-speed flow of ethylene glycol. The boiling liquids were saturated n-pentane, R-113, acetone, methanol ethanol, benzene, and isopropanol. Boiling results include nucleate and transition boiling in all the test liquids, but film boiling was achieved only with methanol. The measured peak heat fluxes are well correlated by available predictions. The methanol experiments clearly display two transition boiling curves, one obtained on increasing the cylinder temperature from nucleate boiling, the other on decreasing the cylinder temperature from film boiling. For the cases in which the highest cylinder temperature reached only into the transition regime, a single transition boiling curve resulted.

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XIAO, BOQI, ZONGCHI WANG, and BOMING YU. "A FRACTAL ANALYSIS OF SUBCOOLED NUCLEATE POOL BOILING." Fractals 16, no. 01 (March 2008): 1–9. http://dx.doi.org/10.1142/s0218348x0800382x.

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A fractal model for the subcooled nucleate pool boiling heat transfer is proposed in this paper. The analytical expressions for the subcooled nucleate pool boiling heat transfer are derived based on the fractal distribution of nucleation sites on boiling surfaces. The proposed fractal model for the subcooled nucleate pool boiling heat transfer is found to be a function of wall superheat, liquid subcooling, fractal dimension, the minimum and maximum active cavity size, the contact angle and physical properties of fluid. No additional/new empirical constant is introduced, and the proposed model contains less empirical constants than the conventional models. The model predictions are compared with the existing experimental data, and fair agreement between the model predictions and experimental data is found for different liquid subcoolings.

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Danish, Mohd, Mohammed K. Al Mesfer, Khursheed B. Ansari, Mudassir Hasan, Abdelfattah Amari, and Babar Azeem. "Predicting Conduction Heat Flux through Macrolayer in Nucleate Pool Boiling." Energies 14, no. 13 (June 28, 2021): 3893. http://dx.doi.org/10.3390/en14133893.

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In the current work, the heat flux in nucleate pool boiling has been predicted using the macrolayer and latent heat evaporation model. The wall superheat (ΔT) and macrolayer thickness (δ) are the parameters considered for predicting the heat flux. The influence of operating parameters on instantaneous conduction heat flux and average heat flux across the macrolayer are investigated. A comparison of the findings of current model with Bhat’s decreasing macrolayer model revealed a close agreement under the nucleate pool boiling condition at high heat flux. It is suggested that conduction heat transfer strongly rely on macrolayer thickness and wall superheat. The wall superheat and macrolayer thickness is found to significantly contribute to conduction heat transfer. The predicted results closely agree with the findings of Bhat’s decreasing macrolayer model for higher values of wall superheat signifying the nucleate boiling. The predicted results of the proposed model and Bhat’s existing model are validated by the experimental data. The findings also endorse the claim that predominant mode of heat transfer from heater surface to boiling liquid is the conduction across the macrolayer at the significantly high heat flux region of nucleate boiling.

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Danish, Mohd, and Mohammed Al Mesfer. "Developing a Mathematical Model for Nucleate Boiling Regime at High Heat Flux." Processes 7, no. 10 (October 11, 2019): 726. http://dx.doi.org/10.3390/pr7100726.

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A mathematical model has been developed for heat exchange in nucleate boiling at high flux applying an energy balance on a macrolayer. The wall superheat, macrolayer thickness, and time are the parameters considered for predicting the heat flux. The influence of the wall superheat and macrolayer thickness on average heat flux has been predicted. The outcomes of the current model have been compared with Bhat’s constant macrolayer model, and it was found that these models are in close agreement corresponding to the nucleate pool boiling regime. It was concluded that the wall superheat and macrolayer thickness contributed significantly to conduction heat transfer. The average conduction heat fluxes predicted by the current model and by Bhat’s model are in close agreement for a thinner macrolayer of approximately 50 µm. For higher values of the wall superheat, which corresponds to the nucleate pool boiling condition, the predicted results strongly agree with the results of Bhat’s model. The findings also validate the claim that conduction across the macrolayer accounts for the main heat transfer mode from the heater surface to boiling liquid at high heat flux in nucleate pool boiling.

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Everts, M., M. Welzl, and D. Brüggemann. "The effective use of focused shadowgraphy for single bubble nucleate pool boiling investigations." Journal of Physics: Conference Series 2766, no. 1 (May 1, 2024): 012149. http://dx.doi.org/10.1088/1742-6596/2766/1/012149.

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Abstract Nucleate pool boiling is known for its high heat transfer coefficients. Despite being widely implemented, the prediction of nucleate pool boiling mechanisms remains complex and single bubble heat transfer analysis is helpful to simplify the problem. Owing to the interesting bubble behaviour during nucleate pool boiling, publications tend to focus on the bubble dynamics while the experimental setup is only briefly discussed. Small but critical information on the experimental setup is often omitted, which makes it challenging or even impossible to reproduce or compare experimental data. Therefore, the purpose of this study is to provide a systematic approach to using focused shadowgraphy for the investigation of single bubble dynamics using R245fa. A pool boiling experimental setup has been built and equipped with temperature, pressure and heat flux sensors, as well as a high-speed camera and light source. The nucleate pool boiling takes place at a single cavity on a copper block. The influences of the heat transfer surface area, light source, and diffuser films were investigated to provide a systematic approach to the use of focused shadowgraphy for the investigation of single bubble dynamics.

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Tanaka, Yoshito, Masato Yoshino, and Tetsuo Hirata. "Lattice Boltzmann Simulation of Nucleate Pool Boiling in Saturated Liquid." Communications in Computational Physics 9, no. 5 (May 2011): 1347–61. http://dx.doi.org/10.4208/cicp.141109.161210s.

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AbstractA thermal lattice Boltzmann method (LBM) for two-phase fluid flows in nucleate pool boiling process is proposed. In the present method, a new function for heat transfer is introduced to the isothermal LBM for two-phase immiscible fluids with large density differences. The calculated temperature is substituted into the pressure tensor, which is used for the calculation of an order parameter representing two phases so that bubbles can be formed by nucleate boiling. By using this method, two-dimensional simulations of nucleate pool boiling by a heat source on a solid wall are carried out with the boundary condition for a constant heat flux. The flow characteristics and temperature distribution in the nucleate pool boiling process are obtained. It is seen that a bubble nucleation is formed at first and then the bubble grows and leaves the wall, finally going up with deformation by the buoyant effect. In addition, the effects of the gravity and the surface wettability on the bubble diameter at departure are numerically investigated. The calculated results are in qualitative agreement with other theoretical predictions with available experimental data.

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Tzan, Ying Liang, and Yu Min Yang. "Experimental Study of Surfactant Effects on Pool Boiling Heat Transfer." Journal of Heat Transfer 112, no. 1 (February 1, 1990): 207–12. http://dx.doi.org/10.1115/1.2910346.

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In the first part of this work, nucleate boiling of aqueous solutions of sodium lauryl sulfate (SLS) over relatively wide ranges of concentration and heat flux was carried out in a pool boiling apparatus. The experimental results show that a small amount of surface active additive makes the nucleate boiling heat transfer coefficient h considerably higher, and that there is an optimum additive concentration for higher heat fluxes. Beyond this optimum point, further increase in additive concentration makes h lower. In the second part of this work, nucleate boiling heat transfer rate for n-propanol-water binary mixtures with various amounts of sodium lauryl sulfate were measured in the same pool boiling apparatus. The importance of the mass diffusion effect, which is caused by preferential evaporation of the more volatile component at the vapor-liquid interface on the boiling of the binary mixture, has been confirmed. However, it is shown that the effect exerted by the addition of a surfactant dominates over the mass diffusion effect in dilute binary mixtures.

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Onishi, Shunsuke, Haruhiko Ohta, Nobuo Ohtani, Yuta Fukuyama, and Hiroyuki Kobayashi. "BOILING HEAT TRANSFER BY NUCLEATE BOILING OF IMMISCIBLE LIQUIDS." Interfacial Phenomena and Heat Transfer 1, no. 1 (2013): 63–80. http://dx.doi.org/10.1615/interfacphenomheattransfer.2013007205.

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33

Sakashita, Hiroto, and Toshiaki Kumada. "Method for predicting boiling curves of saturated nucleate boiling." International Journal of Heat and Mass Transfer 44, no. 3 (February 2001): 673–82. http://dx.doi.org/10.1016/s0017-9310(00)00104-6.

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34

Sathyabhama, Alangar, and Ramakrishna Hegde. "Prediction of nucleate pool boiling heat transfer coefficient." Thermal Science 14, no. 2 (2010): 353–64. http://dx.doi.org/10.2298/tsci1002353s.

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The correct prediction of the heat transfer performance of the boiling liquid within the evaporator of a refrigeration unit is one of the essential features for the successful operation of the whole unit. There are many correlations available in the literature for the prediction of boiling heat transfer coefficient of pure components. Eight heat transfer pool-boiling correlations that are well known in the literature have been selected and their prediction accuracy has been assessed against experimental data of ammonia available in the literature. The analysis concludes that within the investigated ranges of boiling conditions, the Kruzhilin, Kutateladze, Labuntsov, Mostinski nucleate pool-boiling correlations are the most accurate among those assessed.

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35

Parker, Jack L., and Mohamed S. El-Genk. "Effect of Surface Orientation on Nucleate Boiling of FC-72 on Porous Graphite." Journal of Heat Transfer 128, no. 11 (March 13, 2006): 1159–75. http://dx.doi.org/10.1115/1.2352783.

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Effects of orientations of porous graphite and smooth copper surfaces, measuring 10mm×10mm, on saturation nucleate boiling and critical heat flux (CHF) of FC-72 dielectric liquid and of liquid subcooling (0, 10, 20, and 30K) on nucleate boiling in the upward facing orientation are investigated. Inclination angles (θ) considered are 0deg (upward-facing), 60, 90, 120, 150, and 180deg (downward facing). The values of nucleate boiling heat flux, nucleate boiling heat transfer coefficient (NBHTC), and CHF are compared with those measured on the smooth copper surface of the same dimensions and CHF values on both copper and porous graphite are compared with those reported by other investigators on the smooth surfaces and microporous coatings. Results demonstrated higher NBHTC and CHF on porous graphite, particularly in the downward-facing orientation (θ=180deg). In the upward-facing orientation, NBHTCs on both surfaces decrease with increased subcooling, but increase with increased surface superheat reaching maxima then decrease with further increase in surface superheat. In saturation boiling on copper and both saturation and subcooled boiling on porous graphite these maxima occur at or near the end of the discrete bubble region, and near CHF in subcooled boiling on copper. Maximum saturation NBHTC on porous graphite increases with decreased surface superheat and inclination angle, while that on copper increases with increased surface superheat and decreased surface inclination. At low surface superheats, saturation nucleate boiling heat flux increases with increased inclination, but decreases with increased inclination at high surface superheats, consistent with previously reported data for dielectric and nondielectric liquids. The fractional decreases in saturation CHF with increased θ on smooth copper and microporous coatings are almost identical, but markedly larger than on porous graphite, particularly in the downward-facing orientation. In this orientation, saturation CHF on porous graphite of 16W∕cm2 is much higher than on copper (4.9W∕cm2) and as much as 53% of that in the upward-facing orientation, compared to only ∼18% on copper.

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36

Park, K.-J., D. Jung, and S. E. Shim. "Nucleate boiling heat transfer coefficients of halogenated refrigerants up to critical heat fluxes." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 223, no. 6 (February 13, 2009): 1415–24. http://dx.doi.org/10.1243/09544062jmes1356.

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In this work, nucleate pool boiling heat transfer coefficients (HTCs) of five refrigerants of differing vapour pressures are measured on a horizontal, smooth copper surface of 9.53×9.53 mm. The tested refrigerants are R123, R152a, R134a, R22, and R32 and HTCs are taken from 10 kW/m2 to the critical heat flux (CHF) of each refrigerant. Wall and fluid temperatures are measured directly by thermocouples located underneath the test surface and in the liquid pool, respectively. Test results show that nucleate pool boiling HTCs of halogenated refrigerants increase as the heat flux and vapour pressure increase. This typical trend is maintained even at high heat fluxes above 200 kW/m2. Zuber's prediction equation for CHF is quite accurate showing a maximum deviation of 21 per cent for all refrigerants tested. For all refrigerants, Stephan and Abdelsalam's well-known correlation underpredicted nucleate boiling HTC data up to the CHF with an average deviation of 21.3 per cent, while Cooper's correlation overpredicted the data with an average deviation of 14.2 per cent. On the other hand, Gorenflo's and Jung et al.'s correlations showed 5.8 and 6.4 per cent deviations, respectively, in the entire nucleate boiling range up to the CHF.

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37

XIAO, BOQI, SONGHUA GAO, and LINGXIA CHEN. "A FRACTAL MODEL FOR NUCLEATE POOL BOILING OF NANOFLUIDS AT HIGH HEAT FLUX INCLUDING CHF." Fractals 18, no. 04 (December 2010): 409–15. http://dx.doi.org/10.1142/s0218348x10004932.

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A fractal model for nucleate pool boiling of nanofluids at high heat flux and critical heat flux (CHF) is developed based on the fractal distribution of nanoparticles and nucleation sites on boiling surfaces in this paper. The formula of calculating high heat flux and CHF for nanofluids in nucleate pool boiling is given by taking into account heat convection between nanoparticles and liquids due to the Brownian motion of nanoparticles in fluids. The proposed model is expressed as a function of temperature of nanofluids, the effective thermal conductivity of nanofluids, the average size of nanoparticles, the fractal dimension of nanoparticles and nucleation sites, the nanoparticles volume fraction of suspension, and physical properties of fluids. No additional/new empirical constant is introduced in this fractal model. An agreement between the proposed model predictions and experimental data is found. The validity of the fractal model for nucleate pool boiling of nanofluids at high heat flux and CHF is thus verified.

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38

Tao, Jin Liang, Xin Liang Wang, Pei Hua Shi, and Xiao Ping Shi. "Pool Boiling Heat Transfer with Nanotube Arrays Surface on Titanium." Advanced Materials Research 550-553 (July 2012): 2913–16. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.2913.

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In this paper, a new porous coating was formed directly on the surface of titanium metal via anodic oxidation. And by the SEM, the morphology of the coating, which is composed of well-ordered perpendicular nanotubes, was characterized. Moreover, taking deionized water as the test fluid, a visualization study of the coating on its pool boiling heat transfer performance was made. The results demonstrated that compared with the smooth surface, the nucleate boiling heat transfer coefficient can increase 3 times while the nucleate boiling super heat was reduced 30%.

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39

Sides, Paul J. "A Thermocapillary Mechanism for Lateral Motion of Bubbles on a Heated Surface During Subcooled Nucleate Boiling." Journal of Heat Transfer 124, no. 6 (December 1, 2002): 1203–7. http://dx.doi.org/10.1115/1.1517268.

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Both thermocapillary flow and the concerted motion of bubbles toward each other in subcooled nucleate boiling have been mentioned in the literature on boiling phenomena, but never associated with each other. Also, it has been shown in previously unrelated contributions that thermocapillary flow around bubbles of sparingly soluble gas can cause those bubbles to aggregate on a warm surface. The conjunction of these observations leads to the hypothesis that mutual entrainment in thermocapillary flow might drive bubbles toward each other during nucleate boiling of a subcooled liquid. An approximate equation for estimating the observability of such motion is presented. The effect would be especially important in cases where the bubble release rate is low such as boiling on horizontal down-facing surfaces and boiling in microgravity.

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40

Osakabe, Masahiro, Masakatsu Nagai, and Ikuya Haze. "Effect of Fouling on Nucleate Boiling." JOURNAL OF THE MARINE ENGINEERING SOCIETY IN JAPAN 32, no. 1 (1997): 50–55. http://dx.doi.org/10.5988/jime1966.32.50.

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41

Baker, John, and A. K. Krishna Prasad. "Nucleate Pool Boiling over Vertical Steps." Journal of Thermophysics and Heat Transfer 13, no. 3 (July 1999): 308–13. http://dx.doi.org/10.2514/2.6460.

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42

ITO, Takehiro. "Augmentation of nucleate boiling heat transfer." Transactions of the Japan Society of Mechanical Engineers Series B 52, no. 482 (1986): 3417–21. http://dx.doi.org/10.1299/kikaib.52.3417.

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43

Vadlamudi, Sai Raja Gopal, Arun Kumar Nayak, Dinesh K. Chandraker, and Arnab Dasgupta. "MODELING OF DEPARTURE FROM NUCLEATE BOILING." Annual Review of Heat Transfer 22, no. 1 (2019): 89–108. http://dx.doi.org/10.1615/annualrevheattransfer.2020033347.

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44

van der Geld, C. W. M., C. H. M. Baltis, G. J. M. Priems, and T. Baki. "Some problems in nucleate flow boiling." MATEC Web of Conferences 18 (2014): 01003. http://dx.doi.org/10.1051/matecconf/20141801003.

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45

Wang, H., X. F. Peng, B. X. Wang, and D. J. Lee. "Jet flow phenomena during nucleate boiling." International Journal of Heat and Mass Transfer 45, no. 6 (March 2002): 1359–63. http://dx.doi.org/10.1016/s0017-9310(01)00246-0.

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46

Hapke, Ingo, Hartwig Boye, and Jürgen Schmidt. "Onset of nucleate boiling in minichannels." International Journal of Thermal Sciences 39, no. 4 (April 2000): 505–13. http://dx.doi.org/10.1016/s1290-0729(00)00206-4.

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47

Cooper, M. G. "Flow boiling—the ‘apparently nucleate’ regime." International Journal of Heat and Mass Transfer 32, no. 3 (March 1989): 459–64. http://dx.doi.org/10.1016/0017-9310(89)90133-6.

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48

Kenning, D. B. R. "Wall temperature patterns in nucleate boiling." International Journal of Heat and Mass Transfer 35, no. 1 (January 1992): 73–86. http://dx.doi.org/10.1016/0017-9310(92)90009-h.

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49

Passos, J. C., E. L. da Silva, and L. F. B. Possamai. "Visualization of FC72 confined nucleate boiling." Experimental Thermal and Fluid Science 30, no. 1 (October 2005): 1–7. http://dx.doi.org/10.1016/j.expthermflusci.2005.01.008.

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50

Myers, J. E. "Short-lived sites in nucleate boiling." AIChE Journal 31, no. 9 (September 1985): 1441–45. http://dx.doi.org/10.1002/aic.690310906.

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Journal articles on the topic 'Nucleate boiling'

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