摘要
90°弯管的Z形组合是电厂各种管路系统中典型的形变件组合形式,因管路布置空间狭小,故弯管间会产生不同程度的局部阻力相邻影响。采用Realizable k-ε湍流模型对两种间距的组合弯管进行数值模拟研究,采用间距为5倍管径的组合弯管试验结果对数学模型参数及方法进行了验证,并据此开展了间距为0的组合弯管数值预报模拟。通过对比分析两种组合弯管轴向流速、横断面二次流及阻力损失沿程变化,结果表明,两种组合弯管在下游弯管中流速分布表现出较大差异,弯管间距为0时下游弯管内水流轴向流速分布更加不均匀、二次流发展更成熟,组合弯管综合局部阻力损失更大。
The Z -type pipes with two 90° bends are important fittings in power plant piping systems and affected by limited space in power plant adjacent influence of local resistance occur. This paper had simulated the Z - type combination of bend with spacer lengths of 5 and 0 diameters based on the Realizable k - ε model and verified the mathematical model. Based on this pitch the Z - shaped bend combinations which spacer lengths was 0 diameter were forecast, through comparative analysis with spacer lengths of 5 diameters condition further elaborated variation of resistance loss when water flows through the elbow and its adjacent impact mechanism. The results show that the downstream velocity distribution shows a greater difference, the axial flow velocity distribution downstream of bend with spacer lengths of 0 shows more uniform, secondary flow development shows more mature and the comprehensive local resistance loss shows greater.
出处
《人民黄河》
CAS
北大核心
2015年第5期107-111,共5页
Yellow River
关键词
组合弯管
局部阻力
相邻影响
流速分布
压力分布
弯管二次流
combined bend
local resistance
adjacent influence
velocity distribution
pressure distribution
secondary flow of bend
