Effects of surface modification on the pool boiling heat transfer of MWNTs/water nanofluids. (December 2016)

• Record Type: Journal Article
• Authors: Xing, Meibo; Yu, Jianlin; Wang, Ruixiang
• Is Part Of: International journal of heat and mass transfer. Volume 103(2016:Dec.)
• Page Start: 914
• Page End: 919
• Publication Date: 2016-12
• Subjects: Carbon nanotube -- Nanofluid -- Boiling heat transfer -- Surface modification; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2016.07.053
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: Influence of surface modification on pool boiling of CNTs nanofluids was studied. Maximum HTC enhancements are 34.2% and 53.4% for MWNTs-COOH and MWNTs-OH nanofluids. Covalent modification nanofluid can avoid the deposition of CNTs and benefit to HTC. Abstract: The influences of covalent and non-covalent functionalization on the pool boiling heat transfer performance of MWNTs nanofluids were experimentally investigated under different weight concentrations. Relevant pool boiling heat transfer coefficients (HTCs) of MWNTs nanofluids were measured on a cooper flat surface in a pool. The obtained results are further compared with that of the deionized water as a base fluid. The results show that the MWNTs nanofluid with CTAB as non-covalent modification presents poor HTCs, which decreases with increasing the MWNTs concentration due to the deposition of nanoparticles and lower contact angle between nanofluids and heating surface. However, the MWNTs-COOH and MWNTs-OH nanofluids using the COOH and OH groups as covalent modifications show higher pool boiling HTCs than the base fluid, and they increase as the MWNTs concentration increases. The maximum HTC enhancements can reach 34.2% and 53.4% for MWNTs-COOH and MWNTs-OH nanofluids, respectively. This implies the covalent modifications for the MWNTs nanofluid could avoid the deposition of nanoparticles and benefit to HTC enhancements.