CAJ | 학술논문

为研究水泵水轮机反水泵区的压力脉动特性，以某抽水蓄能电站模型水泵水轮机为研究对象，基于分离涡湍流方法（detached eddy simulation，DES），对水泵水轮机反水泵工况进行了数值模拟。探讨了全流道三维湍流场特性，并与试验结果相对比，分析了水泵水轮机在反水泵工况区压力脉动特性。结果表明，反水泵工况下，转轮与导叶之间和尾水管内的主频均为0.143倍转频，主频幅值占混频幅值比例分别达到12%和34.6%。通过流场分析，发现尾水管锥管段内的螺旋形涡带结构是导致这种低频脉动的主要原因。同常规运行工况相比，反水泵工况区的不稳定流场会导致压力脉动相对幅值的突增，引起机组剧烈的振动，严重影响机组的安全运行。
위연구수빙수륜궤반수빙구적압력맥동특성，이모추수축능전참모형수빙수륜궤위연구대상，기우분리와단류방법（detached eddy simulation，DES），대수빙수륜궤반수빙공황진행료수치모의。탐토료전류도삼유단류장특성，병여시험결과상대비，분석료수빙수륜궤재반수빙공황구압력맥동특성。결과표명，반수빙공황하，전륜여도협지간화미수관내적주빈균위0.143배전빈，주빈폭치점혼빈폭치비례분별체도12%화34.6%。통과류장분석，발현미수관추관단내적라선형와대결구시도치저충저빈맥동적주요원인。동상규운행공황상비，반수빙공황구적불은정류장회도치압력맥동상대폭치적돌증，인기궤조극렬적진동，엄중영향궤조적안전운행。
To study the pressure fluctuation characteristics of the pump-turbine at reverse pump mode,the numerical simulation which used the detached eddy simulation(DES) was carried out at reverse pump mode,based on the model pump-turbine in a pumped storage power station in China. The turbulence char?acteristics of the full three-dimensional flow field was investigated and compared with the experimental re?sults. The pressure fluctuation characteristics of the model pump-turbine at reverse pump mode was ana?lyzed. The results showed that, under reverse pump conditions, the dominating frequency between the guide vanes and runner is 0.143fn(fn is the rotation frequency of runner) as well as the draft, and the am?plitude of dominating frequency reached 12 % and 34.6 % respectively, accounted for the mixing frequen?cy. The flow field analysis suggested that the spiral vortex structure in the draft tube was the main reason which causes this low frequency pressure fluctuation. Compared with the common operating conditions, the unsteady flow at reverse pump mode resulted in the sudden increase of the relative amplitude of pressure. As a results,it led to the unit vibration and affected the safe operation seriously.