Kai Qi , Zirui Li , Haiyang Li , Jun Wang , Yongchang Chen , Guodong Xia
{"title":"引入表面活性剂的纳米通道中热渗透流动方向反转可调","authors":"Kai Qi , Zirui Li , Haiyang Li , Jun Wang , Yongchang Chen , Guodong Xia","doi":"10.1016/j.icheatmasstransfer.2025.109288","DOIUrl":null,"url":null,"abstract":"<div><div>Thermo-osmosis is a fluid flow phenomenon in a nanochannel caused by thermal gradients. Generally, reversing the direction of thermo-osmosis requires structural modifications, which limit practical applications. This paper proposes a surfactant-based method to reverse the direction of thermo-osmosis without altering the nanochannel. Molecular dynamics simulations demonstrate that the direction and strength of thermo-osmotic flow in nanochannels can be tuned by varying the surfactant concentration. The introduction of surfactants into the fluid significantly alters the distribution of interfacial free energy. By calculating the potential of mean force, it is found that the addition of the surfactant can reverse the flow direction from positive (high-to-low temperature) to negative (low-to-high temperature), which is attributed to the sign change in the slope of the potential of mean force distribution along the flow direction. Numerical studies further quantify the influence of channel width, surfactant hydrophilicity, and system temperature on the critical reversal concentration. This work presents a tunable, structure-independent method for reversing the direction of thermo-osmosis, thereby advancing applications in adaptive nanofluidics and energy-efficient thermal management.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"167 ","pages":"Article 109288"},"PeriodicalIF":6.4000,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Tunable direction reverses of thermo-osmotic flow in a nanochannel by introducing surfactant\",\"authors\":\"Kai Qi , Zirui Li , Haiyang Li , Jun Wang , Yongchang Chen , Guodong Xia\",\"doi\":\"10.1016/j.icheatmasstransfer.2025.109288\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Thermo-osmosis is a fluid flow phenomenon in a nanochannel caused by thermal gradients. Generally, reversing the direction of thermo-osmosis requires structural modifications, which limit practical applications. This paper proposes a surfactant-based method to reverse the direction of thermo-osmosis without altering the nanochannel. Molecular dynamics simulations demonstrate that the direction and strength of thermo-osmotic flow in nanochannels can be tuned by varying the surfactant concentration. The introduction of surfactants into the fluid significantly alters the distribution of interfacial free energy. By calculating the potential of mean force, it is found that the addition of the surfactant can reverse the flow direction from positive (high-to-low temperature) to negative (low-to-high temperature), which is attributed to the sign change in the slope of the potential of mean force distribution along the flow direction. Numerical studies further quantify the influence of channel width, surfactant hydrophilicity, and system temperature on the critical reversal concentration. This work presents a tunable, structure-independent method for reversing the direction of thermo-osmosis, thereby advancing applications in adaptive nanofluidics and energy-efficient thermal management.</div></div>\",\"PeriodicalId\":332,\"journal\":{\"name\":\"International Communications in Heat and Mass Transfer\",\"volume\":\"167 \",\"pages\":\"Article 109288\"},\"PeriodicalIF\":6.4000,\"publicationDate\":\"2025-06-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Communications in Heat and Mass Transfer\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0735193325007146\",\"RegionNum\":2,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MECHANICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Communications in Heat and Mass Transfer","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0735193325007146","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MECHANICS","Score":null,"Total":0}
Tunable direction reverses of thermo-osmotic flow in a nanochannel by introducing surfactant
Thermo-osmosis is a fluid flow phenomenon in a nanochannel caused by thermal gradients. Generally, reversing the direction of thermo-osmosis requires structural modifications, which limit practical applications. This paper proposes a surfactant-based method to reverse the direction of thermo-osmosis without altering the nanochannel. Molecular dynamics simulations demonstrate that the direction and strength of thermo-osmotic flow in nanochannels can be tuned by varying the surfactant concentration. The introduction of surfactants into the fluid significantly alters the distribution of interfacial free energy. By calculating the potential of mean force, it is found that the addition of the surfactant can reverse the flow direction from positive (high-to-low temperature) to negative (low-to-high temperature), which is attributed to the sign change in the slope of the potential of mean force distribution along the flow direction. Numerical studies further quantify the influence of channel width, surfactant hydrophilicity, and system temperature on the critical reversal concentration. This work presents a tunable, structure-independent method for reversing the direction of thermo-osmosis, thereby advancing applications in adaptive nanofluidics and energy-efficient thermal management.
期刊介绍:
International Communications in Heat and Mass Transfer serves as a world forum for the rapid dissemination of new ideas, new measurement techniques, preliminary findings of ongoing investigations, discussions, and criticisms in the field of heat and mass transfer. Two types of manuscript will be considered for publication: communications (short reports of new work or discussions of work which has already been published) and summaries (abstracts of reports, theses or manuscripts which are too long for publication in full). Together with its companion publication, International Journal of Heat and Mass Transfer, with which it shares the same Board of Editors, this journal is read by research workers and engineers throughout the world.