Numerical simulation of stability behaviors and heat transfer   characteristics for near-critical fluid microchannel flows

doi:10.1016/j.enconman.2015.12.031

CORC > 北京大学 > 工学院

	Numerical simulation of stability behaviors and heat transfer characteristics for near-critical fluid microchannel flows
	Chen, Lin ; Zhang, Xin-Rong ; Okajima, Junnosuke ; Komiya, Atsuki ; Maruyama, Shigenao
刊名	ENERGY CONVERSION AND MANAGEMENT
	2016
关键词	Near-critical fluids Heat transfer Microchannel Energy conversion Carbon dioxide SUPERCRITICAL CARBON-DIOXIDE SOLAR COLLECTOR MICRO-CHANNELS CO2 CONVECTION REGION
DOI	10.1016/j.enconman.2015.12.031
英文摘要	This paper deals with the CO2 near-critical convective flow inside channels of micro-scale. Under near critical conditions, the CO2 fluid is very much expandable/compressible, the density and thermal conductivity change to be near one order of magnitude lower when temperature goes near the critical point. At the same time the Prandtl number and specific heat also form high peaks. In microchannels the effect of natural convection becomes much smaller and the highly thermal expansive fluid with very small thermal diffusivity will act like a periodic thermal plume structure evolution mode. The current study, transient stability and heat transfer characteristics of near-critical microchannel flow are analyzed by solving conservative equations of Mass, Momentum and Energy together with non-Boussinesq incorporation of thermal physical properties. The numerical study is conducted under the ranges of epsilon(T) = 0.00023 - 0.06533 and epsilon(P) = 0.01626 - 0.21951 (for critical distance parameters) with boundary heat flux (from several hundreds to 50,000 W/m(2)). It is found that in microchannels vortex flow is generated by applied boundary heat flux. The thin hot boundary perturbation and thermal-mechanical process of near-critical fluids are major factors. The local span-wise and horizontal parameter changes are also analyzed for the unique near-critical fluid flow. The heat transfer characteristics, especially horizontal acceleration and expanding features are also discussed in this study. (C) 2015 Elsevier Ltd. All rights reserved.; National Science Foundation of China [51276001]; Common Development Fund of Beijing; Global COE Program of Tohoku University (Japan): "World Center of Education and Research for Trans-disciplinary Flow Dynamics"; SCI(E); EI; ARTICLE; chenlinpkucoe@gmail.com; 407-418; 110
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/437682]
专题	工学院
推荐引用方式 GB/T 7714	Chen, Lin,Zhang, Xin-Rong,Okajima, Junnosuke,et al. Numerical simulation of stability behaviors and heat transfer characteristics for near-critical fluid microchannel flows[J]. ENERGY CONVERSION AND MANAGEMENT,2016.
APA	Chen, Lin,Zhang, Xin-Rong,Okajima, Junnosuke,Komiya, Atsuki,&Maruyama, Shigenao.(2016).Numerical simulation of stability behaviors and heat transfer characteristics for near-critical fluid microchannel flows.ENERGY CONVERSION AND MANAGEMENT.
MLA	Chen, Lin,et al."Numerical simulation of stability behaviors and heat transfer characteristics for near-critical fluid microchannel flows".ENERGY CONVERSION AND MANAGEMENT (2016).