摘要
为研究离心泵启动瞬态过程的内部流动机理,建立了求解叶轮启动和加速过程非定常流动的数学模型,以三维模型泵为对象进行启动过程内部流动的数值模拟.采用RNGk-ε湍流模型计算叶轮启动过程内部非定常流动结构和演化过程,得到不同时刻的瞬态外特性曲线,并与定常计算结果进行对比.定性分析了离心泵在启动过程中的瞬态效应,得到叶片及蜗壳压力分布的变化规律.从叶片的压力分布图也清楚地看出压力的不平衡分布,说明存在严重的压力脉动现象,这是引起叶轮不稳定振动的主要原因.
In order to investigate the relationship between explicit transient performance and inner transient flow mechanism during starting period of a centrifugal pump,a mathematical model for unsteady starting and acceleration process was established,and the simulation was carried out to study the inner flow of a three dimensional centrifugal pump during the starting period.The RNG k-ε model was adoped as the turbulence closure.The transient flow structure and its evolutionary process during the blade staring period were analyzed.The explicit transient characteristic curve versus time was also given and compared with that of quasi-steady hypothesis.The transient effect induced by the pump start-up was studied qualitatively.The pressure distributions in impeller and volute were displayed to indicate pressure unbalance and serious pressure pulsation phenomenon,and which are the main reasons that induce impeller instabi-lity.
出处
《排灌机械工程学报》
EI
2010年第2期122-126,共5页
Journal of Drainage and Irrigation Machinery Engineering
基金
国家重大装备研制项目(00-318-06-04)
关键词
离心泵
非定常流动
启动过程
压力分布
叶轮振动
centrifugal pump
nonstationary flow
starting period
pressure distribution
impeller vibration
