摘要
为揭示单-双蜗壳离心泵的不同水力特性,应用商业软件FLUENT,采用RNGk-ε湍流模型和滑移网格技术,对单-双蜗壳双吸离心泵进行不同工况下三维非定常湍流数值模拟,得到不同蜗壳隔舌区计算点的压力脉动情况,并对其进行频域分析.结果表明:单蜗壳离心泵在设计工况及大流量工况下,压力脉动频率以叶片通过频率为主;在小流量工况下,压力脉动频率以低于1倍叶片通过频率为主,在0.6倍设计流量工况下,其压力脉动最大幅值约为设计工况下1.13倍.双蜗壳离心泵在小流量、设计流量及大流量工况下,压力脉动频率均以叶片通过频率为主,在0.6、0.8和1.2倍设计工况下,其压力脉动最大幅值分别约为设计工况的6.59、3.12和4.55倍.相比较于单蜗壳泵,双蜗壳泵能有效地平衡径向力,在偏离设计工况下径向力变化不大.
In order to reveal the difference of hydraulic characteristics between single and double volute centrifugal pumps, their three-dimensional non-stationary turbulent flow was numerically simulated with commercial software FLUENT, RNG κ-ε turbulence model, and sliding mesh technology under different operational conditions. The pressure fluctuation near volute tongue was obtained and the frequency spectra at corresponding monitoring point for different volutes were analyzed. The results showed that the blade passing frequency dominated the pressure fluctuations near the volute tongue under design and large flow rate condition for single volute centrifugal pump. Under small flow rate condition, the frequency less than the blade passing frequency became dominative in the pressure fluctuations. Under condition of 60% de- sign flow rate, the maximum pressure fluctuation amplitude was about 1.13 times larger than the ampli- tude at design flow rate. For the double volute pump the blade passing frequency dominated the pressure fluctuations near the volute tongue under conditions of design and off-design flow rate. Under conditions of 60%, 80% and 120% design flow rate, the pressure fluctuation amplitudes were respectively 6.59, 3. 12 and 4. 55 times larger than the amplitude at design flow rate. Compared with the single volute pump, the double volute pump exhibited the ability to balance effectively the radial force, and the change of radial force at off-design flow rate was little.
出处
《兰州理工大学学报》
CAS
北大核心
2014年第4期51-55,共5页
Journal of Lanzhou University of Technology
关键词
双吸离心泵
单蜗壳
双蜗壳
压力脉动
径向力
double-suction centrifugal pump
single volute
double volute
pressure fluctuation
radial force
