Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology an...Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology and engineering condition of Qishan Coal Mine in Xuzhou, the failure characteristics of pump chambers at the –1000 m level show that the main cause can be attributed to the spatial effect induced by intersectional chambers, where one pump is constructed per well. We developed an opti-mized design of the pump room, in which the pump wells in the traditional design are integrated into one compounding well. We suggest that the new design can limit the spatial effect of intersectional chambers during construction given our relevant numerical simulation. The new design is able to simplify the structure of the pump chamber and reduce the amount of excavation required. Based on a bolt-mesh-anchor with a rigid gap coupling supporting technology, the stability of pump chamber can be improved greatly.展开更多
Due to the limited output capability of piezoelectric diaphragm pumps, the driving voltage is frequently increased to obtain the desired output. However, the excessive voltage application may lead to a large deformati...Due to the limited output capability of piezoelectric diaphragm pumps, the driving voltage is frequently increased to obtain the desired output. However, the excessive voltage application may lead to a large deformation in the piezoelectric ceramics, which could cause it to breakdown or become damaged. Therefore, increasing the number of chambers to obtain the desired output is proposed. Using a check-valve quintuple-chamber pump with quintuple piezoelectric actuators, the characteristics of the pump under different driving modes are investigated through experiments. By changing the number and connection mode of working actuators, pump performances in terms of flow rate and backpressure are tested at a voltage of 150 V with a frequency range of 60 Hz -400 Hz. Experiment results indicate that the properties of the multiple-chamber pump change significantly with distinct working chambers even though the number of pumping chambers is the same. Pump performance declines as the distance between the working actuators increases. Moreover, pump performance declines dramatically when the working piezoelectric actuator closest to the outlet is involved. The maximum backpressures of the pump with triple, quadruple, and quintuple actuators are increased by 39%, 83%, and 128%, respectively, compared with the pump with double working actuators; the corresponding maximum flow rates of the pumps are simply increased by 25.9%, 49.2%, and 67.8%, respectively. The proposed research offers practical guidance for the effective utilization of the multiple-chamber pumps under different driving modes.展开更多
为满足“双碳”目标下新型电力系统灵活调节需求,发展经济高效的储能技术势在必行,抽水蓄能耦合压缩空气储能系统(pumped hydro compressed air energy storage,PH-CAES)因其兼具抽水蓄能高效与压缩空气储能能量密度高、调节范围宽的优...为满足“双碳”目标下新型电力系统灵活调节需求,发展经济高效的储能技术势在必行,抽水蓄能耦合压缩空气储能系统(pumped hydro compressed air energy storage,PH-CAES)因其兼具抽水蓄能高效与压缩空气储能能量密度高、调节范围宽的优势而逐渐兴起。该文首先对PH-CAES的工作原理和技术特点进行了详细阐述,并与其他大规模新型物理储能技术路线进行对比分析;其次,结合PH-CAES的技术特点,梳理总结了PH-CAES电站建库选址优化、水气共容舱可靠储气和液体活塞高效运行3方面的研究现状;最后,分析了PH-CAES的未来发展趋势,从选址规划、流程优化和运行控制等方面梳理了建议关注的重点方向,以期为PH-CAES相关研究提供有益借鉴。展开更多
基金supported by the Major Project of the National Basic Research Program of China (No2006CB202200)the Program for New Century Excellent Talents in Uni-versity (NoNCET07-0800)the Special Fund for Basic Research and Operating Expenses of the China University of Mining & Technology, Beijing and the Academician workstation in enterprise of Jiangsu Province (No.BM2009563)
文摘Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology and engineering condition of Qishan Coal Mine in Xuzhou, the failure characteristics of pump chambers at the –1000 m level show that the main cause can be attributed to the spatial effect induced by intersectional chambers, where one pump is constructed per well. We developed an opti-mized design of the pump room, in which the pump wells in the traditional design are integrated into one compounding well. We suggest that the new design can limit the spatial effect of intersectional chambers during construction given our relevant numerical simulation. The new design is able to simplify the structure of the pump chamber and reduce the amount of excavation required. Based on a bolt-mesh-anchor with a rigid gap coupling supporting technology, the stability of pump chamber can be improved greatly.
基金Supported by National Natural Science Foundation of China(Grant Nos.51205366,51205367,51377147)Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ13E050007)
文摘Due to the limited output capability of piezoelectric diaphragm pumps, the driving voltage is frequently increased to obtain the desired output. However, the excessive voltage application may lead to a large deformation in the piezoelectric ceramics, which could cause it to breakdown or become damaged. Therefore, increasing the number of chambers to obtain the desired output is proposed. Using a check-valve quintuple-chamber pump with quintuple piezoelectric actuators, the characteristics of the pump under different driving modes are investigated through experiments. By changing the number and connection mode of working actuators, pump performances in terms of flow rate and backpressure are tested at a voltage of 150 V with a frequency range of 60 Hz -400 Hz. Experiment results indicate that the properties of the multiple-chamber pump change significantly with distinct working chambers even though the number of pumping chambers is the same. Pump performance declines as the distance between the working actuators increases. Moreover, pump performance declines dramatically when the working piezoelectric actuator closest to the outlet is involved. The maximum backpressures of the pump with triple, quadruple, and quintuple actuators are increased by 39%, 83%, and 128%, respectively, compared with the pump with double working actuators; the corresponding maximum flow rates of the pumps are simply increased by 25.9%, 49.2%, and 67.8%, respectively. The proposed research offers practical guidance for the effective utilization of the multiple-chamber pumps under different driving modes.
文摘为满足“双碳”目标下新型电力系统灵活调节需求,发展经济高效的储能技术势在必行,抽水蓄能耦合压缩空气储能系统(pumped hydro compressed air energy storage,PH-CAES)因其兼具抽水蓄能高效与压缩空气储能能量密度高、调节范围宽的优势而逐渐兴起。该文首先对PH-CAES的工作原理和技术特点进行了详细阐述,并与其他大规模新型物理储能技术路线进行对比分析;其次,结合PH-CAES的技术特点,梳理总结了PH-CAES电站建库选址优化、水气共容舱可靠储气和液体活塞高效运行3方面的研究现状;最后,分析了PH-CAES的未来发展趋势,从选址规划、流程优化和运行控制等方面梳理了建议关注的重点方向,以期为PH-CAES相关研究提供有益借鉴。
