Availability analysis of two dimensional nucleation on cylindrical substrates. (July 2019)

• Record Type: Journal Article
• Authors: Singha, Sanat Kumar; Das, Prasanta Kumar; Maiti, Biswajit
• Is Part Of: International journal of heat and mass transfer. Volume 137(2019)
• Page Start: 390
• Page End: 399
• Publication Date: 2019-07
• Subjects: Heterogeneous nucleation -- Solidification -- Availability -- Exergy -- Free-energy -- Nucleation barrier; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2019.03.139
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: An availability analysis is studied for heterogeneous 2D nucleation. Free-energy maximization is adopted for thermodynamic formulation. The effects of system geometry and substrate wettability are discussed. Nucleation barrier height has lower values in case of concave substrate. Barrier related to flat substrate is in between that of convex and concave substrates. Abstract: Within the framework of the classical availability of heterogeneous nucleation, a scaled exergetic model has been developed to elucidate the two-dimensionality effects on the potency factor which is an explicit dimensionless scaled parameter for the nucleation barrier height. The effects of system geometry and substrate wettability on the thermodynamics of heterogeneous nucleation on a two-dimensional curved substrate are studied. The difference in the potency factor between two-dimensional nucleation on a convex and a flat substrate is always positive and has a maximum value for a given size factor. The regime of the associated contact angle related to maxima are in the cluster-phase-philic regime irrespective of the substrate size or the three phases associated with heterogeneous nucleation. On the other hand, the difference in the potency factor between heterogeneous nucleation on a concave and a planar substrate is always negative and has a minimum value for a given size factor. In this case, the regime of the associated contact angle related to maxima are in the cluster-phase-phobic regime irrespective of the substrate size or the three phases associated with heterogeneous nucleation. The potency factor has lower values in case of concave substrate and has higher values in case of convex substrate and heterogeneous nucleation on a flat substrate is always in between that of the convex substrate and the concave substrate.