Imperial College London
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Dr Giovanni Giustini

Faculty of Engineering, Department of Mechanical Engineering

Honorary Lecturer
 
 
 
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Contact

 

+44 (0)20 7594 9681g.giustini12 Website

 
 
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Location

 

City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Giustini:2019:10.1115/1.4036572,
author = {Giustini, G and Walker, SP and Sato, Y and Niceno, B},
doi = {10.1115/1.4036572},
journal = {Journal of Heat Transfer: Transactions of the ASME},
title = {CFD analysis of the transient cooling of the boiling surface at bubble departure},
url = {http://dx.doi.org/10.1115/1.4036572},
volume = {139},
year = {2019}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Component-scale computational fluid dynamics (CFD) modeling of boiling via heat flux partitioning relies upon empirical and semimechanistic representations of the modes of heat transfer believed to be important. One such mode, “quenching,” refers to the bringing of cool water to the vicinity of the heated wall to refill the volume occupied by a departing vapor bubble. This is modeled in classical heat flux partitioning approaches using a semimechanistic treatment based on idealized transient heat conduction into liquid from a perfectly conducting substrate. In this paper, we apply a modern interface tracking CFD approach to simulate steam bubble growth and departure, in an attempt to assess mechanistically (within the limitations of the CFD model) the single-phase heat transfer associated with bubble departure. This is in the spirit of one of the main motivations for such mechanistic modeling, the development of insight, and the provision of quantification, to improve the necessarily more empirical component scale modeling. The computations indicate that the long-standing “quench” model used in essentially all heat flux partitioning treatments embodies a significant overestimate of this part of the heat transfer, by a factor of perhaps ∼30. It is of course the case that the collection of individual models in heat flux partitioning treatments has been refined and tuned in aggregate, and it is not particularly surprising that an individual submodel is not numerically correct. In practice, there is much cancelation between inaccuracies in the various submodels, which in aggregate perform surprisingly well. We suggest ways in which this more soundly based quantification of “quenching heat transfer” might be taken into account in component scale modeling.
AU  - Giustini,G
AU  - Walker,SP
AU  - Sato,Y
AU  - Niceno,B
DO  - 10.1115/1.4036572
PY  - 2019///
SN  - 0022-1481
TI  - CFD analysis of the transient cooling of the boiling surface at bubble departure
T2  - Journal of Heat Transfer: Transactions of the ASME
UR  - http://dx.doi.org/10.1115/1.4036572
VL  - 139
ER  -
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