The impacting mechanism of surface properties on flow and heat transfer features in nanochannel. (September 2021)

• Record Type: Journal Article
• Authors: Yao, Shuting; Wang, Jiansheng; Liu, Xueling
• Is Part Of: International journal of heat and mass transfer. Volume 176(2021)
• Publication Date: 2021-09
• Subjects: Rough channel -- Convective heat transfer -- Nanostructure morphology period -- Flow resistance; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2021.121441
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: Nanoscale convective heat transfer considering flow resistance is investigated. Combing weak wall-fluid interaction with roughness helps synthesis performance. Smaller morphology period outperforms other periods in rough nanochannel. Dense rough morphology is beneficial for heat transfer and drag reduction jointly. Abstract: Convective heat transfer of hot fluid flowing through a cold parallel plate nanochannel with constant wall temperature is investigated with molecular dynamics. The effects of surface properties including rough morphology and wall-fluid interaction on the heat transfer and flow characteristics are probed. Different surface wettability characterized by the strong and weak wall-fluid interaction as well as five rough morphologies corresponding to various nanostructure morphology periods, are considered. It is noteworthy that the rough morphology and wall-fluid interaction are key parameters for affecting the flow and heat transfer characteristics. The results show that flow resistance and Nusselt number decrease with the increase of rough morphology period as well as the decrease of wall-fluid interaction. Under the same wall-fluid interaction, the best heat transfer enhancement in rough channel is obtained at the morphology period of 12 Å, while a minimum flow resistance in rough channel is obtained at the morphology period of 48 Å. Another novelty finding is that the combination of surface rough morphology and weak wall-fluid interaction will bring a favorable impact on the heat transfer enhancement and drag reduction. Under the weak wall-fluid interaction, the synthesis performance coefficient corresponding to the rough morphology period of 12 Å is highest among all considered rough morphologies, which indicates that the rough morphology with morphology period of 12 Å is optimal to reduce the flow resistance and improve heat transfer performance jointly.