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Structural optimization and design of purging plug for improving its service performance

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Journal of Iron and Steel Research International 2022年第4期29卷 628-635页

作者： Fang-guan Tan Sheng-li Jin Zhu He Ya-wei Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina National-Provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan 430081HubeiChina Chair of Ceramics Montanuniversitaet LeobenLeoben 8700Austria

Purging plug with slits is widely used in the secondary refining process,and its service life determines the downtime and production *** achieve a good performance in service life,optimizing the geometric structure of the slit,which can alleviate the stress concentration around the slit,was employed using the finite plate ***,the performance of the purging plugs with different shapes of slits in the refining effect was investigated by conducting the water model *** numerical simulation results showed that the appropriate shapes of slits could alleviate the stress concentration *** the water model experiment,the mixing time of the purging plug with circular slits is lesser than that of the purging plug with rectangular slits when the gas flow is less than 6.02 L/*** with the rectangular slits,the circular slits are detrimental to smaller and well-distributed ***,the inclusion removal rate of the purging plug with circular slits is approximately 10%larger than that of the purging plug with the rectangular slits.

关键词： Purging plug Stress concentration Water model experiment Mixing time Inclusion removal Ladle metallurgy

HYDRAULIC CHARACTERISTICS OF plug ENERGY DISSIPATER IN FLOOD DISCHARGE TUNNEL

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Journal of Hydrodynamics 2009年第6期21卷 799-806页

作者： TIAN Zhong XU Wei-Lin WANG Wei LIU Shan-Jun State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

The hydraulic characteristics of three types of plugs, namely, the single plug, the stepped plug and the gradually contracted plug were studied by means of experimental and numerical simulations. Main research findings are as follows. For the single plug, the pressure recovery lengths inside and after the plug range from 0.63-1.05 times and 2.02-2.84 times of the tunnel diameter, respectively. For the stepped plug, the lengths are 0.24-0.32 times and 1.62-2.84 times of the tunnel diameter, respectively. The best ratio of the inlet diameter to the outlet diameter of the gradually contracted plug can be expressed by a linear function. The relationship between the head loss coefficient and the area contraction ratio is obtained. The incipient cavitation numbers of different plugs are experimentally and numerically determined, and the incipient cavitation numbers are expressed by a formula. Model experiment with scale of 1：50 was carried out on a pressure tunnel with three-stage gradually contracted plugs. The results show that this type of energy dissipater is suitable for spill tunnels of high head （nearly 200 m） and large flow rate （nearly 2500 m^3/s）.

关键词： plug incipient cavitation number energy dissipater CFD

Analytical Model of Temperature Field in Unsteady Stage of Friction plug Welding

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第5期36卷 789-797页

作者： YAN Chongjing ZHENG Yongle College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China Shanghai Aircraft Design and Research Institute Shanghai 201206P.R.China

The temperature field in unsteady phase greatly affects the quality of friction plug welding(FPW).An analytical model is put forward to correlate the process parameters and the temperature field in unsteady phase of *** the von Mises criterion for plastic deformation and linearizing the heat flux,the model is achieved by Laplace *** predicated peak temperature and peak time agree with the experiment data,with errors of about 4%and 8%,of AA7075-T6 FPW.

关键词： friction plug welding(FPW) unsteady stage temperature field analytical model

Comparison on Hydraulic Characteristics Between Orifice Plate and plug

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Journal of Shanghai Jiaotong university(Science) 2014年第4期19卷 476-480页

作者：艾万政吴建华 School of Navigation Zhejiang Ocean University School of Hydropower Hohai University

Orifice plate energy dissipater as well as plug energy dissipater, as a kind of effective energy dissipater with characteristics of simple structure, convenient construction and high energy dissipation ratio, has become welcomed more and more by hydraulics researchers. The two kinds of energy dissipaters with sudden reduction and sudden enlargement forms are similar in energy dissipation mechanism, but there are differences in energy dissipation characteristics and cavitation characteristics. In the present paper, the differences between orifice plate and plug in energy loss coefficient, relating to their energy dissipation ratio, in the backflow region length, relating to their energy loss coefficient, and in the lowest wall pressure coefficient, relating to their cavitations risk, were analyzed by numerical simulations and physical experiment, and their features in above three aspects were also revealed. The results of research in the present paper demonstrate that the backflow region length of orifice plate is longer than that of plug at the same contraction ratio, the lowest wall pressure coefficient of plug is smaller than that of orifice plate at the same contraction ratio, and the energy loss coefficient of orifice plate is bigger than that of plug, which illustrates that plug is superior to orifice plate in resistance cavitation damage at the same contraction ratio.

关键词： orifice plate plug energy loss coefficient backflow region length lowest wall pressure coefficient

Strategic adjustment of copulatory plug size in a nematode

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Current Zoology 2019年第5期65卷 571-577页

作者： Jorge Canales-LAZCANO Jorge Contreras-GARDUNO Carlos CORDERO Posgrado en Ciencias Biomedicas Institute)de EcologiaUNAMCircuito Exterior S/Nanexo al Jardfn Botanico exteriorCiudad UniversitariaCiudad de MexicoMexico Escuela Nacional de Estudios Superiores Universidad Nacional Autonoma de MexicoUnidad MoreliaAntigua Carretera a Patzcuaro No.8701Col.Ex-Hacienda San Jose de la HuertaMoreliaMichoacanMexico Departamento de Ecologia Evolutiva Instituto de EcologlaUNAMCircuito Exterior S/Nanexo al Jardin Botanico exteriorCiudad UniversitariaCiudad de MexicoMexico

Copulatory plugs(CP)are substances produced during copulation that block the genital openings of the *** several species of Nematoda,males produce CP that are thought to impede female remating and thus sperm *** relatively large size of the CP in several nematodes,and its evolutionary loss in self-fertilizing populations of Caenorhabditis elegans,suggests that CP are costly to *** CP production is costly,the application of basic concepts of strategic ejaculation theory suggests a modulated allocation of CP in response to sperm competition *** hypothesis led us to predict that males perceiving a higher risk of sperm competition will produce larger *** tested these ideas with the entomopathogenic,gonochoristic nematode Rhabditis *** first experiment provides evidence suggesting that production of CP is costly,because the size of CP is negatively affected by stressful conditions(high population density,small male adult size,and suboptimal food type).The results of our second experiment support the prediction that males adjust the size of CP to sperm competition risk:the average size of CP increased as the number of males competing for one female ***,our study supports the idea that in *** the production of CP is costly for males and that the size of the CP produced is influenced by sperm competition risk.

关键词： copulatory plug sexual selection sperm competition strategic ejaculation nematodes

A new weld repair technique for friction stir welded aluminium structure:inertia friction pull plug welding

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China Welding 2017年第4期26卷 56-64页

作者： Wang Guoqing Zhao Yanhua Zhang Lina Bai Jingbin Zhu Ruican China Academy of Launch Vehicle Technology Beijing100076 Capital Aerospace Machinery Company Beijing100076

The paper gives an analysis on technical characteristics of repair techniques for friction stir welding defects. To overcome the defects,a new repair technique, inertia friction pull plug welding( IFPPW), was researched and its equipment was developed as well. Elementary datum was achieved by investigating the influences of technological parameters on mechanical properties and by analyzing the structural characteristics of repair joint with IFPPW. The study shows that the stability and reliability of welding process of IFPPW can be guaranteed through the constant energy from the *** with the advantages of friction pull plug welding,the IFPPW,free from back anvil,is considered as a promising technique in repair of termination keyhole of bobbin tool friction stir welding and point-like defects in aluminum alloy welding.

关键词： defect repair equipment inertia friction pull plug welding technological parameters

APPLICATIONS AND MANUFACTURE OF THE MICROSCALE LONG-OPTICAL-PATH ELECTROCHEMICAL CELL WITH A plug-IN THIN-LAYER ELECTRODE

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Chinese Chemical Letters 1993年第8期4卷 725-728页

作者： Zhang Yu YU Mao Chun JING Shen Hua MIAO Department of Chemistry,Qufu Normal University,Qufu Shandong,273165

The construction and characteristics of a microscale long-optical-path electrochemi- cal cell with a plug-in thin-layer electrode are *** ferricyanide as the test species,the thermodynamic parameters of electron trans... 详细信息

关键词： APPLICATIONS AND MANUFACTURE OF THE MICROSCALE LONG-OPTICAL-PATH ELECTROCHEMICAL CELL WITH A plug-IN THIN-LAYER ELECTRODE SCE plug

The Long-Term Clinical Efficacy of Smart plug in the Treatment of Aqueous Tear Deficiency Dry Eye: Results of a 5-Year Study

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Open Journal of Ophthalmology 2020年第1期10卷 21-27页

作者： Zhaoxia Kuang Yong Yao Ye Yuan Yueting Ma Guanglin Chen Yingying Su Xingkai Zhang Vishal Jhanji Dennis Lam Department of Cornea and Ocular Surface Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong Shantou China Department of Cornea and Ocular Surface C-MER Shenzhen Dennis Lam Eye Hospital Shenzhen China C-MER Kunming Eye Hospital Kunming China Department of Cornea and Ocular Surface Dongguan Aier Eye Hospital Dongguan China

Background: Dry eye syndrome, which affects 10% to 20% of adults, is a disorder of the tear film and is associated with symptoms of ocular discomfort. Smart plug is a mechanical treatment in which the tear drainage system is blocked in order to aid in the preservation of natural tears on the ocular surface. Purpose: To evaluate the long-term clinical efficacy of Smart plug in the treatment of aqueous tear deficiency dry eye. Patients and Methods: Retrospective study. Three hundred and two patients with aqueous tear deficiency dry eye were enrolled and all the patients accepted the punctual plug of Smart plug from Jan. 2011 to Jan. 2016. The clinical symptoms, Schirmer’s I test, Fluorescein staining (FL), tear break up time (TBUT), and complications were observed and analyzed. Results: Three hundred and two patients (604 eyes) were treated with Smart plug (22 cases accepted upper and lower punctual plug, 280 cases only lower punctual plug). There were 109 males (36.1%) and 193 females (63.9%) with a mean age of 44.54 years old (Range from 25 to 83 years). Ten cases required the upper Smart plug after lower punctual plug insertion because of no significantly improved symptoms. Smart plug was removed in 3 patients (1%) due to tearing. Six patients had mild postoperative tearing and no special treatment was required. Lacrimal canaliculitis occurred postoperatively in 8 cases (2.6%) (6 lower and 2 upper), and the affected plug was removed and treated with topical antibiotic eye drops. The BUT, SIT and FL scores of all patients were significantly improved from (2.11 ± 1.01, 4.20 ± 1.07, 6.06 ± 1.97) to (4.34 ± 1.22, 9.01 ± 1.56, 2.33 ± 1.28) respectively after at least 36 months of follow-up (All P P Conclusion: During a mean follow-up of 4.3 years, Smart plug is an effective method for the treatment of aqueous tear deficiency dry eye in spite of its postoperative complications such as canaliculitis and tearing.

关键词： Lacrimal Dry Eye Treatment Smart-plug Punctual plug

Design of plug for drawing rifled tubes

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Journal of Harbin Institute of Technology(New Series) 1999年第3期6卷 69-72页

作者：孟晓峰康达昌高西成宋涛

The effect of revend con ede and length of plug on nstalnt nd elimination of distortion of internal spi-ral ribs is theoretically analysed. Metheds of the plug in rifled tubes drawing and a uniform-Pitch plug with a c... 详细信息

关键词： rifled tubes drawing reversed cone plug rib distortion