FLOW RESISTANCE OF COAL WATER SLURRIES IN PIPELINES
Pipeline transportation technology of highly concentrated coal water slurry (CWS) has been found its wide utiliz(t) on in current clean coal technologies including combustion and gasification. As complex two-phase flow, many factors exert effects on its flow properties, including concentration, particle size, temperature, pipe diameter as well as wall slip effect. The objective of this study is to investigate the effects of several factors mentioned above on flow behavior of coal slurries flowing through steel pipes. The tested volume concentration ranges from 41.73％ to 55.11％ and their pressure drops versus flow-rate were characterized in a series of straight pipelines with inner diameters of 25, 32, 40 and 50mm. A procedure combining traditional Moony method and numerical technique based on Tikhonov regularization is used to determine rheology and slip velocity. The results revealed that increasing particle size leads to low friction factor because there are a decrease in fluid viscosity and an increase in wall slippage. Increasing temperature yields a remarkable reduction of flow resistance as a result of reducing viscosity and increasing slip velocity. While increasing concentration leads to complicated results. Critical wall shear stresses are observed in most cases; it exerts significant influence on resistance properties and slip contribution.
high concentration coal water slurry flow resistance
Liangyong CHEN Yufeng DUAN Meng LIU Guohua ZHAO
Key Laboratory of Clean Coal Power Generation and Combustion Technology of Ministry of Education, Southeast University, Nanjing, China
国际会议
第六届煤燃烧国际会议(The 6th International Symposium on Coal Combustion)
武汉
英文
128-136
2007-12-01（万方平台首次上网日期，不代表论文的发表时间）