... ) ] - 1 / 2 On the other hand, particles at the nucleation length to point C should not influence the molten alloy from crucible. Accordingly, we have (25) Z ≤ U w t c + L cr which guarantees δ n  ≥  δ for the molten alloy at higher wheel speeds when U...

... to document bubble dynamics. Boiling mechanisms inherent to subcooling, enhanced surface geometry, and CHF are discussed. flow boiling enhanced surface structured-porous subatmospheric pressure high heat flux water nucleation structured-porous surface screen laminate thermal management...

... – 35 . 10.1016/S0017-9310(02)00257-0 20 Schroder , J. J. , McGill , S. , Dirbach , M. , and Podzelny , E. , 1996 , “ Secondary Nucleation Ambivalent Heat Transfer and Sound Emission in Low Pressure Subcooled Boiling ,” Proceedings of the EUROTHERM Seminar No 48: Pool Boiling...

... at low heat fluxes is due to the fact that the effect of formation of thin sorption layer of nanoparticles on heater surface, which causes deterioration by trapping the nucleation sites, is overshadowed by the increase in microlayer evaporation, which is due to enhancement in thermal conductivity. Same...

...A. Sathyabhama; T. P. Ashok Babu Visualization of bubble nucleation during nucleate pool boiling outside a vertical cylindrical heated surface was done for ammonia-water binary mixture in order to obtain a descriptive behavior of the boiling, which was directly compared with the measured heat...

...Sean J. Penley; R. A. Wirtz Saturated pool-boiling experiments at 1 atm and subatmospheric pressure assess the utility of fine-filament screen-laminate enhanced surfaces as effective bubble nucleation sites. Experiments were conducted on vertically oriented, multilayer laminates in saturated...

... with the corresponding simulation data for the hydrophobic surface of 15 deg inclination. The critical stage of slide-off is also pictorially compared; a discrepancy in the actual time of slide-off in experiments as opposed to simulation is again observed. Soon after slide-off, virgin areas are created, nucleation sites...

... drastically due to the radiation absorbed by the carbon particles and additional nucleation sites formed by carbon particles for heterogeneous decomposition reaction. The present study numerically tries to investigate the above fact by tracking carbon particles in a Lagrangian framework. The results...

... condensation form is still not clear. We suggest a condensation model based on droplet nucleation and growth on elevated precipitates, resulting in short-term steam entrapment after droplet coalescence. According to the wetting theory, this transition state yields increased macroscopic contact angles...

... flow, and the wavy-annular flow. The interaction of the bubble with the pin fins during nucleate boiling from G = 350 kg / m 2 s to G = 827 kg / m 2 s and wall heat fluxes from 10 W / cm 2 to 110 W / cm 2 is detailed. Garimella , S. , and Singhal , V. , 2004 , “ Single-Phase Flow...

... characteristics have been identified and the optimal enhancement requires a balance of the active nucleation sites, bubble flow resistance, natural convection, thin film evaporation, liquid superheating, heat transfer area, bubble coalescence, and liquid reflux resistance. High speed visualization of vapor plug...

.... 121013 ) is verified in this part. In the first step, the model is examined by experiments conducted using R134a covering a range of pressures, inlet subcoolings, and flow velocities. The density of the active nucleation sites is measured and correlated with critical diameter D c and static contact angle...

... a significant change in the nucleate boiling mechanism, which accounted for the largest effect on the heat transfer performance. The porous enhancement structure can be expected to alter the conduction and convection through the liquid film near the plate wall to the extent that the correlation, obtained from...

... 25 06 2009 boiling bubbles capillarity convection nucleation organic compounds surface tension zero gravity experiments boiling variable gravity microgravity thermocapillary convection dissolved gas heater size Pool boiling involves complicated nonlinear processes...

... the bubble formation at the nucleation sites, and significantly improve the nucleate boiling heat transfer. Experiments revealed that its boiling heat transfer enhancement is comparable or in some respect even superior to the commercially available boiling heat transfer enhancement surfaces such as porous...

...Jadran Vrabec; Martin Horsch; Hans Hasse Homogeneous nucleation processes are characterized by the nucleation rate and the critical droplet size. Molecular dynamics simulation is applied for studying homogeneous nucleation during condensation of supersaturated vapors of methane and ethane...

... were conducted using three types of 200 × 253 μ m 2 parallel microchannel devices: with reentrant cavity surface, with interconnected reentrant cavity surface, and with plain surface. The onset of nucleate boiling, CHF condition, and local temperature measurements were obtained and compared in order...

... of the electron gas and transferred to the lattice. The energy equations for the electron and lattice were coupled through an electron-lattice coupling factor. Melting and resolidification were modeled by considering the interfacial energy balance and nucleation dynamics. An iterative solution procedure...

...Brian R. Novak; Edward J. Maginn; Mark J. McCready Heterogeneous bubble nucleation was studied on surfaces having nanometer scale asperities and indentations as well as different surface-fluid interaction energies. Nonequilibrium molecular dynamics simulations at constant normal stress and either...

... not correspond to the steady state. The present modeling by CML is based on the assumption that the flow boiling is governed by (i) nucleation from cavities on the heated surface and migration of vapor into the core, (ii) forced convection, and (iii) phase change in the fluid bulk and mixing. The stirring action...