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HYDRAULIC CHARACTERISTICS OF SLIT-TYPE ENERGY DISSIPA-TERS

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Journal of Hydrodynamics 2012年第6期24卷 883-887页

作者： wu jian-hua MA Fei YAO Li College of Water Conservancy and Hydropower Engineering Hohai University

Slit-Type Energy Dissipater （STED） has been a kind of important devices for energy dissipation. The flow through the STED is longitudinally extended and the velocity is decreased by means of the cross-section increase of the flow, which is closely related to geometric and hydraulic parameters of the STED. Therefore, it is necessary to investigate and control the hydraulic condi- tions through the STED, including the nappe section form, the conversion condition, and the effect of energy dissipation with the geometric and hydraulic parameters. In the present work, ＂I-type＂ and ＂T-type＂ nappe forms were experimentally classified, the con- version conditions of the nappe forms were empirically provided, and the effects of geometric parameters of the STED on energy dissipation were roughly analyzed. It is concluded that the contraction angle of the STED is a key factor influencing the hydraulic characteristics of the STED.

关键词： contraction angle energy dissipation fin nappe form shock wave Slit-Type Energy Dissipater （STED）

HYDRAULIC RESEARCH OF AERATORS ON TUNNEL SPILLWAYS

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Journal of Hydrodynamics 2007年第3期19卷 330-334页

作者： RUAN Shi-ping wu jian-hua wu Wei-wei XI Ru-ze College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China Anhui Institute of Hydraulic Research Bengbu 233000 China

The selection of the configuration and size of an aerator was of importance for a tunnel spillway under the conditions of high speed flows. Experimental investigations were conducted on the effects of entrained air on the tunnel spillway in the Goupitan Project, based on the criterion of gravity similarity and the condition of aerated flow velocity of over 6 m/s, with physical models. The configurations of the aerators were presented of a larger bottom air concentration, to protect the tunnel spillway from cavitation as well as to see no water fills in the grooves.

关键词： cavitation aerator air concentration tunnel spillway the Goupitan Project

Critical size effect of sand particles on cavitation damage

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Journal of Hydrodynamics 2013年第1期25卷 165-166页

作者： wu jian-hua GOU Wen-juan College of Water Conservancy and Hydropower Engineering Hohai University

The critical size of the sand particles in liquid is determined by means of the special vibratory apparatus, and it is related to various effects on the cavitation damage. The increase of the sand size or concentration would aggravate the cavitation damage if their sizes are larger than this critical size, conversely, this damage would be relieved.

关键词： cavitation damage sand particle sand size abrasion

ON ACOUSTIC PERFORMANCE OF MEASURING STRUCTURE FOR CAVITATION NOISE

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Journal of Hydrodynamics 1991年第2期3卷 42-50页

作者： wu, jian-hua Chai, Gong-chun Wang, He-sheng Nanjing Hydraulic Research Inst Nanjing China

The acoustic performance of the structure for measuring cavitation noise is theoretically analysed, and two judging criteria of the acoustic performance of STW (sound transmission window) are presented in this paper. One is of impedance matching between working liquid and STW:ρ1C1 = ρ2C2. The other is of maximum frequency (or minimum wave length) of cavitation noise spectrum: fmax&le c/60D (or λmin/D ≥ 60). If either of the criteria is met reliable measured results of cavitation noise will be obtained. The theoretical results are verified through experiments. According to the criteria, the paper analyses the acoustic performance of routinely used plexiglass STW. The results show that in the research of clear water cavitation the impedance ratio, 2. 18, does not satisfy ρ1C1 = ρ2C2, and fmax&le C/60D hardly holds for actual cavitation noise spectrum. Therefore, plexiglass STW is not good enough for sound transmission. From this point of view, polyethylene is better sound transmission material than plexiglass.

关键词： Acoustic Waves Transmission Glass Acoustic Properties Hydrodynamics Fluid Structure Interaction Polyethylenes Acoustic Properties Water Waves

Disseminated cryptococcal lymphadenitis with negative latex agglutination test

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Chinese Medical Journal 2012年第13期125卷 2393-2396页

作者： XU Xiao-guang BI Xin-ling wu jian-hua XU Hong LIAO Wan-qing Department of Dermatology Changhai Hospital Second Military Medical University Shanghai 200433 China Institute of Dermatology and Mycosis of Changzheng Hospital Second Military Medical University Shanghai 200003 China

We reported an unusual case of disseminated cryptococcal lymphadenitis in an immunocompetent host who presented with fever and lymphadenopathy, which were the only two symptoms and signs. Latex agglutination test of serum and cerebrospinal fluid （CSF） were negative, while lymph node biopsy showed Cryptococcus neoformans. A diagnosis of disseminated cryptococcal lymphadenitis was made. Then the patient was treated with amphotericin B for 15 days as initial therapy and itraconazole for 6 months as maintenance therapy respectively. The patient received re-examination per 6 months and was followed up for 2 years. Swollen lymph nodes diminished gradually, and no fever or other symptoms were found. Latex agglutination test of serum and CSF were negative throughout the follow-up period, and anti-HIV, syphilis and tuberculosis antibody were all negative.

关键词： Cryptococcus neoformans lymphadenitis latex agglutination test immunocompetence

EXPERI MENTAL STUDY ON CAVITATION AND WATER-WING FOR MIDDLE-PIERS OF DISC HARGE TUNNELS

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Journal of Hydrodynamics 2005年第4期17卷 429-437页

作者： wu jian-hua CAI Chang-guang JI Wei RUAN Shi-ping LUO Chao College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China China Hydro Mid-South Design and Research Institute Changsha 410014 China

In construction of high dams, design of a middle-pier, placed in a discharge tunnel to divide it into two parts, is a better choice that could breakthrough the limits of the manufacture and operation of the gate due to the high head to it. However, cavitation and water-wing, a kind of flow striking the top and side walls of the tunnel, induced by the middle-pier, may take place and bring about bad effects on operation of the tunnel. The experiments of the six comparing plans were conducted, consisting of atmospheric and vacuum tank models, and the interesting areas included relationships between discharges and reservoir levels, measurements of side wall pressures, comparisons of water-wing states for the various middle-piers, estimations of the incipient cavitation numbers and the flow cavitation numbers, and analyses of cavitation characteristics for the tunnel. A kind of new bodily form of middle-pier was developed. Water-wing states were better improved and non-cavitation conditions were satisfied.

关键词： discharge tunnel middle-pier cavitation water-wing

HYDRAULIC CHARACTERISTICS OF PARTIAL OPENING OF THE WORKING GATE FOR A DISCHARGE TUNNEL

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Journal of Hydrodynamics 2007年第4期19卷 488-493页

作者： wu jian-hua FENG Shu-rong wu Wei-wei RUAN Shi-ping College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China China Hydro Mid-South Design and Research Institute Changsha 410014 China

The partial opening of the working gate for a discharge tunnel is used more and more widely in the various conditions, such as releasing discharge to meet the needs of the various stages under construction, or of the operations at low reservoir levels. In this article the hydraulic characteristics were investigated of the partial opening of the working gate based on the physical model experiments of the discharge tunnel for the Longtan Hydropower Project, including the discharge coefficient, the surface profile of the free flow section, the bottom pressure distribution of the tunnel with an aerator, the cavity length just from the ramp, and the wall pressure of the curve section of the outlet. Some new issues were discussed and the properties were presented of the partial opening of the gate.

关键词： partial opening hydraulic characteristics working gate discharge tunnel

某工业产业园园区道路水泥稳定钢渣-碎石路用性能研究

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建筑机械 2024年第5期 168-171页

作者：吴建华中铁十九局集团第三工程有限公司辽宁沈阳110136

为研究钢渣在沥青路面半刚性基层中的应用效果,改善路面基层使用性能,文章按照C-B-3级配类型进行3种不同比例的级配设计,采用击实试验和无侧限抗压强度试验测试不同级配试件的性能,并确定最优级配。按照设计配合比制作试件成型,通过测... 详细信息

为研究钢渣在沥青路面半刚性基层中的应用效果,改善路面基层使用性能,文章按照C-B-3级配类型进行3种不同比例的级配设计,采用击实试验和无侧限抗压强度试验测试不同级配试件的性能,并确定最优级配。按照设计配合比制作试件成型,通过测定抗压回弹模量和温缩、干缩性能,综合评定基层路用性能。结果表明,当采用水泥剂量为5.0%,C-B-3骨架密实级配1、钢渣∶碎石=75%∶25%时,混合料试件力学强度和抗裂性能较好,水泥稳定钢渣-碎石基层路用性能最佳,满足道路基层应用要求。

关键词：水泥稳定钢渣-碎石掺配比例力学性能抗裂性能

HYDRAULIC CHARACTERISTICS OF WATER-WINGS FOR THE MIDDLE-PIER OF A DISCHARGE TUNNEL

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Journal of Hydrodynamics 2006年第5期18卷 567-571页

作者： wu jian-hua CAI Chang-guang JI Wei RUAN Shi-ping College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China China Hydropower Mid-South Design and Research Institute Changsha 410014 China

Water-wings, induced by the middle-pier placed in the inlet of a discharge tunnel, have harmful effects on the operation of the discharge tunnel. Based on dimensional analysis and physical model tests, the hydraulic characteristics of water-wings were investigated and their causes were analyzed in this study. The results show that the height and length of the water-wings increased with the increase of three factors, i.e., the Froude number Frd of the outlet of the pressure section, the depth Hc of the water surface concave at the end of the middle-pier, and the impact length Li of the two flows after this end.

关键词： water-wing dimensional analysis discharge tunnel middle-pier