空化文丘里管稳流特性研究Numerical Study on the Steady Flow Characteristics of Cavitation Venturi
吕福炜,宗丹丹,孙静,胡效东
Lv Fuwei,Zong DANDan,Sun Jing,Hu Xiaodong
摘要(Abstract):
基于Realizable k-ε湍流模型和Zwart空化模型,采用计算流体动力学方法(CFD),结合相关文献的研究成果,对某文丘里管的流动进行了模拟计算,研究稳流工作的文丘里管的空化流体动力学特性和稳流特性规律。流量的模拟数值与已有的试验数值吻合较好,误差在5.8%以内,证明数值模拟方法可以用来研究文丘里管的流动特性。通过改变文丘里管的渐缩段入口结构跟渐扩段角度,对其稳流特性进行研究,并得到以下结论:空化现象的出现是文丘里管稳流作用的必要条件。增大文丘里管的渐扩段角度,边界层分离现象更为严重,在尾流区会产生更多的旋涡,加剧了流体的湍流程度,造成了更多能量的不可逆耗散。在一定程度上,湍流程度与文丘里管的稳流性能成正比。湍流愈剧烈,稳流性能愈好。同时圆弧式收缩段结构的文丘里管稳流响应迅速;抛物线、直线式收缩段结构的文丘里管稳流响应较慢。
Based on the Realizable turbulence model and the Zwart cavitation model,the computational fluid dynamics(CFD)method was used to study the cavitation fluid dynamics and steady flow characteristics of the venturi in steady flow operation combined with the research results of related literatures to simulate the flow of a venturi.The simulated values of the flow rate agree well with the existing experimental values with the error within 5.8%,which proves that the numerical simulation method can be used to study the flow characteristics of the venturi.The steady flow characteristics are studied with different inlet structure of the venturi and different angles of the diverging section.Conclusions are obtained:The phenomenon of cavitation is a necessary condition for the steady flow of the venture;The separation of the boundary layer is more serious with the angle of the venturi tube increasing;and more vortices are generated in the wake region,which increases the turbulence of the fluid and causes irreversible dissipation of more energy.To a certain extent,the degree of turbulence is directly proportional to the steady flow performance of the venture;More turbulent the turbulence,the better the steady flow performance;At the same time,the venturi of the arc-shaped contraction section has a steady steady flow response;The steady flow response of the venturi of the parabolic and linear contraction sections is slow.
关键词(KeyWords):
文丘里管;空化;稳流;数值模拟
venturi tube;cavitation;flow controller;numerical simulation
基金项目(Foundation): 山东省重点研发计划项目(2018GGX103019);; 山东省自然科学基金资助项目(ZR2014EEM018)
作者(Author):
吕福炜,宗丹丹,孙静,胡效东
Lv Fuwei,Zong DANDan,Sun Jing,Hu Xiaodong
参考文献(References):
- [1] Kabeel A E,Abdelgaied M.Study on the effect of alumina nano-fluid on sharp-edge orifice flow characteristics in both cavitations and non-cavitations turbulent flow regimes[J].Alexandria Engineering Journal,2016,55(2):1099-1106.
- [2] Qin Z,Alehossein H.Heat transfer during cavitation bubble collapse[J].Applied Thermal Engineering,2016,105:1067-1075.
- [3] Cioncolini A,Scenini F,Duff J,et al.Choked cavitation in micro-orifices:an experimental study[J].Experimental Thermal & Fluid Science,2016,74:49-57.
- [4] Wang H,Xia B,Lu Y,et al.Experimental study on sonic vibrating effects of cavitation water jets and its promotion effects on coalbed methane desorption[J].Fuel,2016,185:468-477.
- [5] Mao Y,Zeng L,Lu Y.Modeling and optimization of cavitation on a textured cylinder surface coupled with the wedge effect[J].Tribology International,2016,104:212-224.
- [6] Wijngaarden L V.Mechanics of collapsing cavitation bubbles[J].Ultrasonics Sonochemistry,2016,29:524-527.
- [7] 龙新平,王炯,左丹,等.文丘里管不同空化阶段空化不稳定特性的试验研究[J].机械工程学报,2018,54(2):209-215.
- [8] Long X,Zhang J,Wang J,et al.Experimental investigation of the global cavitation dynamic behavior in a venturi tube with special emphasis on the cavity length variation[J].International Journal of Multiphase Flow,2016:S0301932216302828.
- [9] Ashrafizadeh S M,Ghassemi H.Experimental and numerical investigation on the performance of small-sized cavitating venturis[J].Flow Measurement & Instrumentation,2015,42:6-15.
- [10] 杨帆,陈伟政,唐学林.空化流动研究进展[J].流体机械,2009,37(11):36-41.
- [11] 王福军.计算流体动力学分析:CFD 软件原理与应用[M].北京:清华大学出版社,2004.
- [12] 刘厚林,刘东喜,王勇,等.三种空化模型在离心泵空化流计算中的应用评价[J].农业工程学报,2012,28(16):54-59.
- [13] 姚博贵,牛步娟,高宁,等.气化炉内部水冷壁排渣口设计和试制[J].压力容器,2019,36(4):68-73.
- [14] 雒定明,张玉明,焦建国,等.高压预冷器管板变形原因分析[J].压力容器,2019,36(4):52-62.
- [15] 雷万庆,张凯,张建晓,等.缠绕管式换热器换热管泄漏失效分析[J].压力容器,2019,36(1):65-71.
- [16] 王国茂,赵潇,魏莉鸿,等.大开挖穿越管道热力耦合分析[J].压力容器,2018,35(2):35-42.
- [17] 万方腾,何立东,丁继超,等.换热器管线阻尼减振技术研究[J].机电工程,2019,36(1):36-39.
- [18] 杨斌.FT合成反应器管束的设计与制造[J].化工设备与管道,2018,55(6):17-21.
- [19] Arakeri V H,Acosta A.Viscous effects in the inception of cavitation[J].Journal of Fluids Engineering,1973,103(2):32-5.