90°弯管Z形组合局部阻力特性研究

来源 :人民黄河 | 被引量 : 0次 | 上传用户:zhouqiangjian
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
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 90 ° elbow Z-combination is a typical form of deformation in various piping systems of power plants. Due to the narrow space of pipeline layout, different degrees of local resistance adjacent effects will occur between elbows. Realizable k-ε turbulence model was used to simulate the elbow joint with two kinds of spacings. The test results of the elbow joint with 5 times of pipe diameter were used to verify the mathematical model parameters and methods. 0 combined bend numerical prediction simulation. The axial flow velocity, cross-sectional secondary flow and the loss of resistance change of the two kinds of combined elbows were compared and analyzed. The results showed that the flow velocity distribution of the two kinds of combined elbows showed great difference in the downstream elbows. The elbows spacing was 0 When the downstream flow within the axial flow velocity distribution is more uneven, the development of secondary flow more mature, combination of pipe local resistance loss greater.
其他文献
该文从挂篮荷载计算、施工流程、支座及临时固结施工、挂篮安装及试验、合拢段施工、模板制作安装、钢筋安装、混凝土的浇筑及养生、测量监控等方面人手,介绍了S226海滨大桥
<正>本文对小儿腹泻患者采用整体护理治疗,取得较好效果,报告如下。1资料与方法1.1临床资料选取2016年3月至2017年3月间我院收治的72例小儿腹泻患者。根据护理方法不同分为观
静脉穿刺术是一项常用的临床技术,提高穿刺成功率,可减轻患者痛苦,减少医患纠纷,提高工作效率,为抢救危重症患者赢得时间.笔者通过20多年临床工作探索,总结以下几种静脉穿刺
期刊