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黄河口实体模型生潮设备和控制技术研究与讨论 被引量:2
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作者 吴国英 刘刚森 《中国水运(下半月)》 2014年第11期190-191,共2页
黄河口模型生潮控制设备,经过改进后采用多台水泵均匀布设,水泵出口增设喇叭形整流罩,每2台水泵并联由1台变频器控制,生潮设备控制采用HMMC2000控制软件进行控制,模型基本能够达到黄河口潮形、潮位的自动模拟相似,但还存在水位滞后问题... 黄河口模型生潮控制设备,经过改进后采用多台水泵均匀布设,水泵出口增设喇叭形整流罩,每2台水泵并联由1台变频器控制,生潮设备控制采用HMMC2000控制软件进行控制,模型基本能够达到黄河口潮形、潮位的自动模拟相似,但还存在水位滞后问题,并针对目前存在的问题对生潮设备中仪器设备提出了改进建议。 展开更多
关键词 黄河口模型 设备 变频控制器
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半导体生产后工序设备中的若干视觉检测与伺服系统设计技术 被引量:12
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作者 胡跃明 吴忻生 +2 位作者 戚其丰 袁鹏 刘海明 《广东自动化与信息工程》 2003年第1期7-9,共3页
针对半导体生产后工序设备中的高速高精度检测与控制问题,首先系统分析了芯片质量检测的任务,并提出了相应的视觉检测算法以及程序设计方法。其次讨论了硬件系统的设计问题,提出了送料系统的立体结构和终端执行机构的双四连杆伺服系统... 针对半导体生产后工序设备中的高速高精度检测与控制问题,首先系统分析了芯片质量检测的任务,并提出了相应的视觉检测算法以及程序设计方法。其次讨论了硬件系统的设计问题,提出了送料系统的立体结构和终端执行机构的双四连杆伺服系统设计方法。从而有效地提高了设备的生产速度和灵活性。 展开更多
关键词 半导体设备 半导体产后工序设备 视觉检测系统 伺服系统 半导体工业
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生瓷片切割设备中工控机和视觉定位系统的应用
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作者 王磊 李玉刚 《科技情报开发与经济》 2010年第30期215-216,共2页
介绍了如何在生瓷片切割设备中使用工控机和视觉定位系统,对多层叠片生瓷片材料上的MARK标记进行识别,保存各种规格的产品参数。
关键词 瓷片切割设备 工控机 视觉定位系统
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椒江模型中生潮机械设备的研制与应用
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作者 金慕光 《河口与海岸工程》 1992年第1期129-136,共8页
关键词 设备 物理模型 流量 减速器
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“联盟—TM号”飞船上的救生设施总体(续)
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作者 王金华 《载人航天信息》 1993年第7期15-20,共6页
关键词 宇宙飞船 命保障系统 设备
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概化弯道段潮汐模型系统设计与制作 被引量:4
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作者 马健 孙东坡 +1 位作者 曹卫平 蒋承杰 《海洋工程》 CSCD 北大核心 2009年第2期104-109,共6页
根据典型弯曲型河口段的宽浅边界形态、水力条件及潮汐特征,依据相似理论确定模型的基本几何及水力参数。分析了河工模型的最大允许变率,借助重力和紊动阻力相似准则确定模型的各项控制比尺。模型由上游延伸段、河道试验段与下游潮汐池... 根据典型弯曲型河口段的宽浅边界形态、水力条件及潮汐特征,依据相似理论确定模型的基本几何及水力参数。分析了河工模型的最大允许变率,借助重力和紊动阻力相似准则确定模型的各项控制比尺。模型由上游延伸段、河道试验段与下游潮汐池组成。采用W形波纹凹槽方式加糙,使模型糙率达到了试验要求。实测资料验证显示了概化模型的合理性。 展开更多
关键词 潮汐弯道段 概化模型 复式断面 控制系统 设备
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大跨度缆索吊锚碇设计与施工 被引量:1
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作者 于进华 王素静 《铁道标准设计》 2001年第5期17-18,共2页
介绍大型临时起重设备简易缆索吊车的锚碇 ,在特殊地理环境中采用岩锚技术进行固定的设计思路和施工方法。
关键词 桥梁 大型起设备 缆索吊车 设计 施工 岩锚技术 锚碇
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中国无线互联业务发展的核心驱动力
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作者 邓永强 《无线互联科技》 2004年第Z1期4-5,共2页
中国无线互联网络越来越多、越来越宽,但是无线互联业务的成功不取决于网络是否先进,而在于是否能够开发出贴近用户的数据多媒体业务。无线互联必须着眼于实际应用,特别是与用户的具体需求相结合,才能具有生机和活力。
关键词 核心驱动力 移动电话用户 数据流量 移动梦网 手机支付 移动游戏 互联时代 通话费 在线银行 设备生
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Research on Protoplast Preparation and Regeneration Conditions of Tremella aurantialba 被引量:2
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作者 贺婷 郭成金 《Agricultural Science & Technology》 CAS 2012年第1期60-63,67,共5页
[Objective] This study aimed to explore the protoplast preparation and re- generation conditions of Tremella aurantialba. [Method] Optimal combination of five factors affecting the protoplast preparation and regenerat... [Objective] This study aimed to explore the protoplast preparation and re- generation conditions of Tremella aurantialba. [Method] Optimal combination of five factors affecting the protoplast preparation and regeneration of Tremella aurantialba was selected by using orthogonal experiment, including enzyme system, culture age, enzymolysis temperature, enzymolysis duration and osmotic stabilizer. [Result] The results showed that there were three release modes of Tremella aurantialba proto- plasts: release from top in the early period of enzymolysis, release from the side and release in situ. The optimal protoplast preparation condition was selecting mycelium cultured in liquid medium for 3 d, for enzymolysis in mixed enzyme solu- tion containing 1% of cellulase +1% of snailase +1% of lywallzyme at 36 ℃; for 4 h, with 0.6 mol/L sucrose as osmotic stabilizer, and the obtained preparation rate had reached 1.76 ×10^7 protoplasts/ml. The optimal regeneration condition was using mycelium cultured in liquid medium for 5 d, for enzymolysis in enzyme solution con- taining 1.5% of lywallzyme at 33 ℃ for 3 h, with 0.6 mol/L sucrose as osmotic sta- bilizer, and the regeneration rate had reached 0.22%. [Conclusion] This study provid- ed valuable support for protoplast fusion, ultraviolet mutation breeding and genetic engineering research. 展开更多
关键词 Tremella aurantialba PROTOPLAST PREPARATION REGENERATION Orthogonalexperiment design
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Can intraluminal devices prevent or reduce colorectal anastomotic leakage:A review 被引量:11
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作者 Annelien N Morks Klaas Havenga Rutger J Ploeg 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第40期4461-4469,共9页
Colorectal anastomotic leakage is a serious complication of colorectal surgery, leading to high morbidity and mortality rates. In recent decades, many strategies aimed at lowering the incidence of anastomotic leakage ... Colorectal anastomotic leakage is a serious complication of colorectal surgery, leading to high morbidity and mortality rates. In recent decades, many strategies aimed at lowering the incidence of anastomotic leakage have been examined. The focus of this review will be on mechanical aids protecting the colonic anastomosis against leakage. A literature search was performed using MEDLINE, EMBASE, and The Cochrane Collaborative library for all papers related to prevention of anastomotic leakage by placement of a device in the colon. Devices were categorised as decompression devices, intracolonic devices, and biodegradable devices. A decompression device functions by keeping the anal sphincter open, thereby lowering the intraluminal pressure and lowering the pressure on the anastomosis. Intracolonic devices do not prevent the formation of dehiscence. However, they prevent the faecal load from contacting the anastomotic site, thereby preventing leakage of faeces into the peritoneal cavity. Many attempts have been made to find a device that decreases the incidence of AL;however, to date, none of the devices have been widely accepted. 展开更多
关键词 Anastomotic leakage Colorectal surgery COMPLICATION RECTUM Device
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How regenerative medicine and tissue engineering may complement the available armamentarium in gastroenterology? 被引量:2
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作者 Marco Carbone Jan Lerut James Neuberger 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第47期6908-6917,共10页
The increasing shortage of donors and the adverse effects of immunosuppression have restricted the impact of solid organ transplantation.Despite the initial promising developments in xenotransplantation,roadblocks sti... The increasing shortage of donors and the adverse effects of immunosuppression have restricted the impact of solid organ transplantation.Despite the initial promising developments in xenotransplantation,roadblocks still need to be overcome and this form of organ support remains a long way from clinical practice.While hepatocyte transplantation may be effectively correct metabolic defects,it is far less effective in restoring liver function than liver transplantation.Tissue engineering,using extracellular matrix scaffolds with an intact but decellularized vascular network that is repopulated with autologous or allogeneic stem cells and/or adult cells,holds great promise for the treatment of failure of organs within gastrointestinal tract,such as endstage liver disease,pancreatic insufficiency,bowel failure and type 1 diabetes.Particularly in the liver field,where there is a significant mortality of patients awaiting transplant,human bioengineering may offer a source of readily available organs for transplantation.The use of autologous cells will mitigate the need for long term immunosuppression thus removing a major hurdle in transplantation. 展开更多
关键词 Regenerative medicine Tissue engineering Organ transplantation Cellular transplantation XENOTRANSPLANTATION
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风险防范视角的农场代购业务纳税筹划策略 被引量:1
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作者 杨志国 王树锋 《金融经济(下半月)》 2014年第12期84-86,共3页
针对农场履行为家庭农场代购生产资料和农业物质装备业务服务中,因会计核算差错遗留纳税风险并已给农场造成巨额经济损失的客观现实,结合会计准则和增值税法律制度规定以及实地调研案例,采用归纳总结、逻辑推理、判断分析等方法,描述了... 针对农场履行为家庭农场代购生产资料和农业物质装备业务服务中,因会计核算差错遗留纳税风险并已给农场造成巨额经济损失的客观现实,结合会计准则和增值税法律制度规定以及实地调研案例,采用归纳总结、逻辑推理、判断分析等方法,描述了国有农场代购农资装备业务的特征,介绍了农场代购业务核算的政策依据,深入地剖析了农场代购业务核算中出现纳税风险表现及危害,并探索了农场代购生资装备业务核算的纳税筹划策略。 展开更多
关键词 农场设备 代购业务核算 会计风险
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Incidence of pocket hematoma after electrophysiological device placement:dual antiplatelet therapy versus low-molecular-weight heparin regimen 被引量:3
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作者 Yan CHEN Yun-Tao LI +8 位作者 Ming-Dong GAO Ze-Chun ZENG Jin-Rong ZHANG Hong-Liang CONG Yin LIU Ru ZHAO Le-Feng WANG Xin-Cun YANG Kang MENG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2014年第3期200-205,共6页
Background Given the increasing number of patients who require dual antiplatelet (DAP) therapy and electrophysiological device (EPD) placement, perioperative antiplatelet management is a current challenge. In this... Background Given the increasing number of patients who require dual antiplatelet (DAP) therapy and electrophysiological device (EPD) placement, perioperative antiplatelet management is a current challenge. In this study, we investigated the incidence of pocket hema-toma formation after EPD placement in patients undergoing DAP therapy or an alternative low-molecular-weight heparin (LMWH) regimen. Methods This clinical observational study was performed from July 2010 to July 2012. In total, 171 patients were enrolled in the analysis after meeting the inclusion criteria. These patients were divided into two groups: 86 patients were treated with DAP therapy at the time of device implantation, and the DAP therapy was discontinued for 5 to 7 days and replaced with enoxaparin before device implantation in the other 85 patients. Adenosine phosphate (ADP)-mediated platelet aggregation and arachidonic acid-induced platelet aggregation were tested preoperatively. We compared the incidence of pocket hematoma between the two groups and the association of pocket hematoma develop-ment with ADP-mediated platelet aggregation and arachidonic acid-induced platelet aggregation.Results The incidence of pocket hema-toma in the patients who continued DAP was lower than that in the patients who replaced the dual antiplatelet regimen with LMWH (3.49%vs. 16.47%, respectively;X2 = 6.66,P 〈 0.01). Among the patients who continued DAP therapies, the rate of ADP-mediated platelet aggre-gation inhibition in patients with pocket hematomas was higher than that in patients without pocket hematomas. None of the patients under-going DAP or enoxaparin therapy developed pocket infection, thromboembolic events, or other serious complications. Multiple logistic re-gression analysis revealed that LMWH therapy was an independent risk factor for the development of pocket hematoma (RR = 0.054, 95%CI = 0.012-0.251). Furthermore, patients undergoing LMWH therapy were 5.1-fold more likely to develop pocket hematomas than were DAP-treated individuals.Conclusion Continuance of DAP therapy does not increase the risk of pocket hematoma formation after EPD placement. 展开更多
关键词 Antiplatelet drug Hematoma Low-molecular-weight heparin Electrophysiological device
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Indoor thermal comfort studies based on physiological parameter measurement and questionnaire investigation 被引量:6
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作者 郑洁 陈良 +1 位作者 李百战 陈露 《Journal of Central South University of Technology》 EI 2006年第4期404-407,共4页
Physiological parameters of people and enact assessment standard of indoor thermal environment that are appropriate to our national conditions were explored from the perspective of physiology. From December 2005 to Ja... Physiological parameters of people and enact assessment standard of indoor thermal environment that are appropriate to our national conditions were explored from the perspective of physiology. From December 2005 to January 2006, nerve conduction velocities and skin temperatures of 20 healthy students were tested with questionnaire investigation. The results show that the nerve conduction velocities as well as skin temperatures present an obvious decline trend in a continuous draught, and that the nerve conduction velocities and skin temperatures have a definite linear relationship. Draught velocity is an important factor in winter that affects body comfort, and the subjects are sensitive to air velocity. 展开更多
关键词 thermal comfort nerve conduction velocity sensory never conduction questionnaire
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Spectrum Sensing Model for Wireless Internet of Things 被引量:1
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作者 温志刚 刘杰 《China Communications》 SCIE CSCD 2011年第1期8-13,共6页
In the last few years, the number of devices operating in wireless Internet of Things (IoT) has experienced tremendous growth. On the other hand, the growth results in spectrum scarcity. Cog- nitive Radio (CR) sys... In the last few years, the number of devices operating in wireless Internet of Things (IoT) has experienced tremendous growth. On the other hand, the growth results in spectrum scarcity. Cog- nitive Radio (CR) systems have been proposed to efficiently exploit the spectra that have been assigned but are underutilized. In this paper, a spectrum sensing model based on Markov chain is proposed to predict the spectrum hole for CR in wireless IoT. Theoretical analysis and simulation results have been evaluated that a Markov model with two- state or four-state works well enough in wireless loT whereas a model with more states is not necessary for it is complex. 展开更多
关键词 Internet of Things Cognitive Radio spectrum hole Markov chain
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Multi Agent Systems for Fault States Diagnostics and Equipment and Process Management of Yogurt Ripening Tank 被引量:1
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作者 Pavel Burian 《Journal of Chemistry and Chemical Engineering》 2011年第2期182-193,共12页
It is impossible to plan in advance unpredictable phenomena at monitoring, diagnosis and control of industrial batch and continuous equipment and processes such as chemical composition of the raw materials, the proces... It is impossible to plan in advance unpredictable phenomena at monitoring, diagnosis and control of industrial batch and continuous equipment and processes such as chemical composition of the raw materials, the process leads to unexpected reactions and changes its parameters, etc. The agent is active, a program entity, has its own ideas how to perform the tasks of the own agenda. Agents perceive, behave "reasonably", communicate with other agents. Agents can represent equipment and operations in batch processes as recommended by the ISA $88. Jadex system is based on Java language and on FIPA org. recommendations. The description of ripening tank T406 and recipe for yogurt production in the holding of MADETA Corp. in the Czech Rep. It is described modeling and displaying of"normal" and error, fault unit state of the ripening tank. Agents are within the Jadex system and describing the behavior of ripening tank T406 with state diagrams-automata and assist in diagnosing of fault states. States are described in XML language-SCXML (State Charts XML). Jadex Control Center-JCC represents a major access point to use for operating in real time. 展开更多
关键词 Multi Agent Systems UML SCXML Jadex Java.
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Cleaning of South African coal using a compound dry cleaning apparatus 被引量:3
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作者 Li Haibin Luo Zhenfu Zhao Yuemin Wu Wanchang Zhang Cuiyu Dai Ningning 《Mining Science and Technology》 EI CAS 2011年第1期117-121,共5页
The compound dry cleaning principle is briefly described.A beneficiation test on South African coal was conducted using a model compound dry cleaning apparatus.Excellent results were obtained and the optimum operating... The compound dry cleaning principle is briefly described.A beneficiation test on South African coal was conducted using a model compound dry cleaning apparatus.Excellent results were obtained and the optimum operating parameters were determined.They are:an amplitude of 3.0 mm,a motor frequency of 47.5 Hz,an air volume of 50%,a transverse angle of 7°,and a longitudinal angle of-2°.These conditions yield a clean coal containing 11%ash and a coal production of 75%.The organic efficiency,η,is 95.86%.These results show that the South African coal can be separated effectively by compound dry cleaning,which will popularize the compound dry cleaning method. 展开更多
关键词 Compound dry cleaning Model apparatus South African coal
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Application of reliability-centered maintenance for productivity improvement of open pit mining equipment:Case study of Sungun Copper Mine 被引量:5
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作者 Amin Moniri Morad Mohammad Pourgol-Mohammad Javad Sattarvand 《Journal of Central South University》 SCIE EI CAS 2014年第6期2372-2382,共11页
Equipment plays an important role in open pit mining industry and its cost competence at efficient operation and maintenance techniques centered on reliability can lead to significant cost reduction.The application of... Equipment plays an important role in open pit mining industry and its cost competence at efficient operation and maintenance techniques centered on reliability can lead to significant cost reduction.The application of optimal maintenance process was investigated for minimizing the equipment breakdowns and downtimes in Sungun Copper Mine.It results in the improved efficiency and productivity of the equipment and lowered expenses as well as the increased profit margin.The field operating data of 10 trucks are used to estimate the failure and maintenance profile for each component,and modeling and simulation are accomplished by using reliability block diagram method.Trend analysis was then conducted to select proper probabilistic model for maintenance profile.Then reliability of the system was evaluated and importance of each component was computed by weighted importance measure method.This analysis led to identify the items with critical impact on availability of overall equipment in order to prioritize improvement decisions.Later,the availability of trucks was evaluated using Monte Carlo simulation and it is revealed that the uptime of the trucks is around 11000 h at 12000 operation hours.Finally,uncertainty analysis was performed to account for the uncertainty sources in data and models. 展开更多
关键词 operating costs maintenance mining dump truck RELIABILITY AVAILABILITY UNCERTAINTY
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Acoustic Conditioning System Development and Conditioning Experiments on Black Seabreams in the Xiangshan Bay Sea Ranch
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作者 HU Qingsong RAHMAN Hafiz Abd ur +2 位作者 JIANG Yazhou ZHANG Shouyu SHENTU Jikang 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期667-674,共8页
Attracting released hatchery-reared fish to designated areas during the growth process is vital to realize the objectives of sea ranching. Based on the bottom artificial reefs and surface kelp culture facilities in th... Attracting released hatchery-reared fish to designated areas during the growth process is vital to realize the objectives of sea ranching. Based on the bottom artificial reefs and surface kelp culture facilities in the Xiangshan Bay sea ranch, we proposed systematic techniques related to acoustic conditioning of the black seabream(Sparus macrocephalus). Experiments conducted in 12 m × 10 m × 1.6 m ponds on Xixuan Island showed that black seabream was positively sensitive to 500–600 Hz periodic signals. Conditioned responses were apparent after 8 d. Two to three days were required for recovery of the memory of a conditioned response after a 20-day interval. According to the practical application requirements in the open sea, unattended acoustic conditioning equipment was developed. The ranching equipment was used in 12 m × 12 m × 2.5 m cages, and the behavior of black seabream juveniles was successfully guided after 7 days. Of the 16000 released fish, 82.5% of them were conditioned with a flexible grading net. To avoid inducing a stress response, the juveniles were released into the sea ranch in situ from the net cage. The acoustic conditioning equipments were moved into the open sea and the aggregation phenomenon of the released fish was observed when the sound was played. After 6 months of investigation and based on Sr+ marking, only one acoustically conditioned fish was found outside the 3.5-km^2 sea ranch area, thereby reached the goal of guiding activity. The practical effect in the Xiangshan Bay sea ranch showed the validity of the acoustic conditioning system, which may contribute to improve the operation of the sea ranches in the East China Sea. 展开更多
关键词 sea ranch black seabream ranching equipment acoustic conditioning aggregation
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Numerical simulation of a self-absorbing microbubble generator for a cyclonic-static microbubble flotation column 被引量:17
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作者 LI Lin LIU Jiongtian +1 位作者 WANG Lijun YU Hesheng 《Mining Science and Technology》 EI CAS 2010年第1期88-92,共5页
The Cyclonic-Static Microbubble Flotation Column (FCSMC) is currently a widely used, novel type of flotation device. The self-absorbing microbubble generator is the core component of this device. The structure of the ... The Cyclonic-Static Microbubble Flotation Column (FCSMC) is currently a widely used, novel type of flotation device. The self-absorbing microbubble generator is the core component of this device. The structure of the microbubble generator directly influences flotation column performance by affecting bubble size and distribution as well as gas holdup in the column. However, the complicated flow inside the generator results in high R&D costs and difficulty in testing. Thus, the CFD software, FLUENT, was used to simulate the gas-liquid two-phase flow inside a self-absorbing microbubble generator. The effect of area ratio, a key structural parameter, was studied in detail. Critical flow-field parameters including velocity, turbulent kinetic energy, minimum static pressure and gas holdup were obtained. The simulation results demonstrate that the optimum area ratio is 3. 展开更多
关键词 self-absorbing microbubble generator flotation column two-phase flow numerical simulation
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