人民黄河
人民黃河
인민황하
Yellow River
2013年
11期
124-126
,共3页
泵输水系统%事故停泵%水锤%空气阀
泵輸水繫統%事故停泵%水錘%空氣閥
빙수수계통%사고정빙%수추%공기벌
pressurize water supply system%accidental pump-stop%water hammer%air valve
结合山西中部某引黄工程,采用流体力学的基本原理和特征线法,在泵出口安装两阶段关闭蝶阀和沿管线布设空气阀联合防护措施下,针对输水系统事故停泵引起的水锤问题进行水力过渡分析和计算,得出管线沿程水锤压力和泵出口断面压力变化过程线。结果表明,泵出口安装两阶段关闭蝶阀对高扬程、长距离管道的水锤防护效果较明显,合理控制快慢关时间及角度能有效降低水击压力、机组倒转和倒泄流量。通过调整空气阀的布设位置、口径及进出流量系数,得出在空气阀流入流量系数为0.975、流出流量系数为0.650、口径为450 mm下的水力过渡过程,管路中最大负压水头控制在-1.6 m以内。可见,沿管线合理布置空气阀能有效降低管道负压。
結閤山西中部某引黃工程,採用流體力學的基本原理和特徵線法,在泵齣口安裝兩階段關閉蝶閥和沿管線佈設空氣閥聯閤防護措施下,針對輸水繫統事故停泵引起的水錘問題進行水力過渡分析和計算,得齣管線沿程水錘壓力和泵齣口斷麵壓力變化過程線。結果錶明,泵齣口安裝兩階段關閉蝶閥對高颺程、長距離管道的水錘防護效果較明顯,閤理控製快慢關時間及角度能有效降低水擊壓力、機組倒轉和倒洩流量。通過調整空氣閥的佈設位置、口徑及進齣流量繫數,得齣在空氣閥流入流量繫數為0.975、流齣流量繫數為0.650、口徑為450 mm下的水力過渡過程,管路中最大負壓水頭控製在-1.6 m以內。可見,沿管線閤理佈置空氣閥能有效降低管道負壓。
결합산서중부모인황공정,채용류체역학적기본원리화특정선법,재빙출구안장량계단관폐접벌화연관선포설공기벌연합방호조시하,침대수수계통사고정빙인기적수추문제진행수력과도분석화계산,득출관선연정수추압력화빙출구단면압력변화과정선。결과표명,빙출구안장량계단관폐접벌대고양정、장거리관도적수추방호효과교명현,합리공제쾌만관시간급각도능유효강저수격압력、궤조도전화도설류량。통과조정공기벌적포설위치、구경급진출류량계수,득출재공기벌류입류량계수위0.975、류출류량계수위0.650、구경위450 mm하적수력과도과정,관로중최대부압수두공제재-1.6 m이내。가견,연관선합리포치공기벌능유효강저관도부압。
Aimed at the problem of water hammer caused by accidental Pump-stop in pressurize water supply systems,using the fluid dynamics the-ory and characteristics method and combining with a Yellow River diversion project in the center of Shanxi,the paper calculated and analyzed the hydraulic transient process under the conditions of protective measures of installing two-stage closed butterfly valve and air valve. The pressure enve-lope of water hammer along the pipeline and the pressure change process of pump outlet cross-section were obtained simultaneously. The numerical results show that the present water hammer protections to the long pipeline system are effective. The water hammer pressure,the unit upside down and inverted vent flow can be effectively reduced by controlling the two stage valve closing time and closing angle. According to the adjusting posi-tion of air valve,the caliber of the valve and inflow and outflow coefficient to control the negative pressure. It is found that the parameters combina-tion in which air valve inflow coefficient is 0. 975,outflow coefficient 0. 65 and caliber 450 mm is suitable for the pumping station. The pipeline maximum negative pressure head control is within -1. 6 m. This shows that the negative pressure of the pipe can be effectively reduced by rational arrangement of the air valve.