Thermal interactions between nucleation sites and the solid wall during pool boiling of a pure fluid: A review

Effect of uniformly and nonuniformly coated Al2O3 nanoparticles over plain glass tube heater on pool boiling heat transfer was studied experimentally. A borosilicate glass tube coated with Al2O3 nanoparticle was used as test heater. The boiling behaviour was studied by using high speed camera. Result obtained for pool boiling shows enhancement in heat transfer for nanoparticle coated surface heater and compared with plain glass tube heater. Also heat transfer coefficient for nonuniformly coated nanoparticles was studied and compared with uniformly coated and plain glass tube. Coating effect of nanoparticles over glass tube increases its surface roughness and thereby creates more nucleation sites.

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Lattice Boltzmann Simulation of Nucleate Pool Boiling in Saturated Liquid

Communications in Computational Physics ◽

10.4208/cicp.141109.161210s ◽

2011 ◽

Vol 9 (5) ◽

pp. 1347-1361 ◽

Cited By ~ 5

Author(s):

Yoshito Tanaka ◽

Masato Yoshino ◽

Tetsuo Hirata

Keyword(s):

Lattice Boltzmann ◽

Solid Wall ◽

Bubble Diameter ◽

Pool Boiling ◽

Nucleate Boiling ◽

Bubble Nucleation ◽

Immiscible Fluids ◽

Nucleate Pool Boiling ◽

Two Phase ◽

Boiling Process

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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Sub-Atmospheric Pressure Pool Boiling of Water on a Screen Laminate-Enhanced, Wavy-Fin Array

Volume 4: Electronics and Photonics ◽

10.1115/imece2010-40678 ◽

2010 ◽

Author(s):

P. J. Laca ◽

R. A. Wirtz

Keyword(s):

Atmospheric Pressure ◽

Pool Boiling ◽

Bubble Nucleation ◽

High Density ◽

Wire Mesh ◽

Effective Surface ◽

Nucleation Sites ◽

Semi Empirical ◽

Very High ◽

Reduced Pressures

Saturated pool boiling on vertically oriented, copper, wavy-fin surfaces in water at reduced pressures is investigated. A lamination of fine-filament, wire mesh is an effective surface enhancement for boiling since the surface can be configured to provide a very high density of potential bubble nucleation sites. Two surfaces are considered: a 0.75mm thick 4-layer laminate with approximately 4000 pores per cm2 and a 0.42mm thick 8-layer laminate with approximately 26,000 pores per cm2. The results show that the 8-layer laminate outperforms the 4-layer laminate. At reduced pressures a reduction in performance is seen for both surfaces. A semi-empirical boiling model is developed. The model predicts the boiling performance of our data within an error of 30%. The model shows that shorter fins improve boiling performance.

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Experiment of Enhanced Pool Boiling Heat Transfer on Coupling Effects of Nano-Structure and Synergistic Micro-Channel

ASME 2019 6th International Conference on Micro/Nanoscale Heat and Mass Transfer ◽

10.1115/mnhmt2019-4215 ◽

2019 ◽

Author(s):

Linsong Gao ◽

Jizu Lv ◽

Minli Bai ◽

Chengzhi Hu ◽

Liqun Du ◽

...

Keyword(s):

Heat Transfer ◽

Boiling Heat Transfer ◽

Capillary Flow ◽

Pool Boiling ◽

Micro Channel ◽

Nano Structure ◽

Pool Boiling Heat Transfer ◽

Wall Superheat ◽

Nucleation Sites ◽

The Heat Transfer Coefficient

Abstract The manipulation of micro- or nano-structure is a promising method to improve pool boiling heat transfer performance. However, most studies just focus on the micro- or nano-structure without considering the combination micro- and nano-structure. In this paper, we fabricated synergistic microchannel, nano-structure, and micro-nano structure surface on the nickel by different technologies. Pool boiling of DI water under saturated condition was experimentally investigated. Result shows at the wall superheat of 18 K, the heat transfer coefficient of micro-nano structure, nano-structure and synergistic micro-channel surface are 16400, 13050, and 13400 W/m2 K higher 89%, 50%, and 54% than that of smooth surface, respectively. The improved heat transfer is attributed to active nucleation sites and capillary flow.

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