摘要：分析了GIS设备内部短路电弧造成的问题,介绍了GIS设备异常时气室压力上升和外壳烧穿时间的计算方法,并初步探查了GIS设备壳体的有效防护措施——压力释放装置的合理设计。同时,以某种550kVGIS设备为例,计算短路电弧出现时气室内部压力变化及壳体烧穿时间,结果表明各气室的壳体设计均满足要求,没有发生壳体烧穿、破裂的可能性。

摘要：LNG运输船在航行中受环境热量渗入和摇晃等影响,液货舱和液货系统中LNG蒸发产生蒸发气(Boil-off Gas,BOG),造成液货舱和液货系统中压力上升,《国际散装运输液化气体船舶构造和设备规则》(IGC Code)要求LNG运输船应有保证其液货舱和液货系统的压力和温度保持在设计限制及载运要求范围内的能力。

摘要：This paper presents the investigation of the effects of suction side squealer tip on the performance of an axial *** experiment is carried out in a single-stage large-scale low-speed *** investigated tip geometries include flat tip as the baseline and suction side squealer *** tip clearance of the baseline is 0.5% of the blade *** static pressure rise characteristic curves of both the rotor and the stage are *** flow field at the exit of the rotor is measured by a 5-hole probe under design and off-design *** static pressure on the endwall of the rotor passage is also *** results show that the pressure rise characteristic curves obtained by measuring the pressure on the end wall are almost unchanged by using the suction side squealer *** measuring results of the 5-hole probe show the static pressure and the total pressure in tip region is slightly greater than that of the flat tip at the design condition at the exit of the *** also leads to greater av-eraged static pressure rise and total *** the near stall condition,the averaged static pressure and total pressure is lower than the baseline which is related to the redistribution of the blade load caused by the suction side squealer tip.

摘要：This paper presents an investigation on the effect of probe support on the flow field of an axial *** experiment is carried out in a large-scale low-speed research compressor.A cylindrical probe support intruding to 50% blade span was installed at 50% chord upstream from the rotor leading *** region from 5° to 32° off the probe support in the direction of rotation at the rotor outlet was measured with a 5-hole probe and a high-response total pressure *** experiment is performed at both near-design and near-stall *** measuring results of 5-hole probe and high-response total pressure probe indicate that the probe blockage effect is different at different blade *** wake of the probe support weakens the leakage vortex intensity at the tip region,leading to greater total pressure *** near-design condition,the presence of probe support has a negative effect on the region from 75% to 92% span,while improves the flow field below 75% *** near stall condition,the probe support has a negative effect on the region from 70% to 90% span,and almost has no influence on the flow field below 70% span.

摘要：该文讲述水轮机组甩负荷时,通过采取分段关闭导叶的措施,降低水击压力和机组转速上升,以改善机组的大波动过渡过程,达到把压力上升和转速上升控制在规范允许范围内的目的。

摘要：依据水力学中水击压力计算公式,对2008年9月24日江西省安福县谷口水库灌溉阀关闭时造成的引水系统损坏事故原因进行分析,对水击压力上升引起的引水系统破坏现场做了相关记录,提出了断流和流量调节装置选用对引水系统影响的问题和相应解决方法。

摘要：2020年以来,新冠疫情蔓延对全球生产生活造成了重大的冲击,经济停摆、生产停滞、供应链中断、全球贸易量大幅萎缩,企业流动性资金压力上升。在此历史背景之下,以习近平同志为核心的党中央科学准确判断国内国际形势发展新变化,审慎作出“加快构建以国内大循环为主体、国内国际双循环相互促进的新发展格局”的重大战略决策,在党的十九届五中全会上被确定为“十四五”时期经济社会发展的指导思想和重要原则。中国企业在此次疫情背景下,如何理解和认知新发展格局,以更高的发展质量引领未来中国经济的发展,加强顶层设计、抓好机遇、谋划布局,对中国企业发展具有重要意义。

摘要：当水轮发电机组甩负荷时,调速器控制水轮机活动关闭导叶,压力管道内产生压力,机组转速上升。对于压力引水管道较长的电站,改变导叶关闭时间,就不一定能同时使压力和转速上升都控制在允许的范围之内。使用调压阀的作用在于:在机组甩负荷、导叶快速关闭的同时相应地打开泄流通道,从而降低水锤压力上升,待导叶全关后,再缓慢关闭,使引水管道的流量变化缓慢,防止引水管道水压升高及机组转速过高。导叶关闭时间T_w≤12s的中小型电站采用调压阀代替调压井后,不但能够节省投资、缩短工期,而且调压阀的布置还不易受地质、地形等条件限制。

摘要：中国石油网消息(特约记者艾艳通讯员刘蕊)“变频器一转,每月至少节省20万元。”8月3日,宁夏石化公司三化肥装置总变6千伏配电室低压配电柜前,电仪三班6名岗位员工算了一笔提质增效账。最近,三化肥装置氨站两台氨输送泵出口设计流量过大,造成液氨装车过程中灌装不及,回流液氨使氨罐温度压力上升。这不仅需要放空部分氨气,而且要频繁启动两台冰机降温,导致电耗升高。电仪部二车间副主任余勇提出,加个变频器,把泵的工频运行方式改成变频运行。技术员和电仪三班员工开展头脑风暴,讨论出具体方案。

摘要：在小型水电站的机组GD2、导叶关闭时间、水工建筑布置已定的情况下,水锤压力上升值过高,不能满足要求时,为了节省投资,可在压力水管上设置金属爆破膜片,当压力超过一定数值时即被击破,泄放一部分高压水,降低水锤压力,以保证压力水管的安全。