Study on Local Resistance of non-Newtonian Power Law Fluid in Elbow Pipes  

作　　者：ZHANG Hao XU Tiantian ZHANG Xinxin WANG Yuxiang WANG Yuancheng LIU Xueting 

机构地区：[1]School of Thermal Energy Engineering,Shandong Jianzhu University [2]Key Laboratory of Renewable Energy Utilization Technologies in Buildings,Ministry of Education [3]Department of Thermal Engineering,University of Science and Technology Beijing

出　　处：《Journal of Thermal Science》2016年第3期287-291,共5页热科学学报（英文版）

基　　金：supported by Shandong Provincial Natural Science Foundation,China(No.ZR2014JL039)

摘　　要：This paper focuses on the flow characteristic and local resistance of non-Newtonian power law fluid in a curved 90° bend pipe with circular cross-sections, which are widely used in industrial applications. By employing nu- merical simulation and theoretical analysis the properties of the flow and local resistance of power law fluid under different working conditions are obtained. To explore the change rule the experiment is carried out by changing the Reynolds number, the wall roughness and differcnt diameter ratio of elbow pipe. The variation of the local resistance coefficient with the Reynolds number, the diameter ratio and the wall roughness is presented comprehensively in the paper. The results show that the local resistance force coefficient hardly changes with Reynolds number of the power law fluid; the wall roughness has a significant impact on the local resistance coefficicnt. As the pipe wall roughness increasing, the coefficient of local resistance force will increase. The main reason of the influence of the roughness on the local resistance coefficient is the increase of the eddy current region in the power law fluid flow, which increases the kinetic energy dissipation of the main flow. This paper provides theoretical and numerical methods to understand the local resistance property of non-Newtonian power law fluid in elbow pipes.

关 键 词：non-Newtonian fluid Local resistance coefficient Reynolds number Bend diameter ratio ROUGHNESS 

分 类 号：O373[理学—流体力学]