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Temperature drop and output work of radial inflow in rotating cavity with finned vortex reducer 认领 引用
1
作者 Jian HE Xiang LUO +2 位作者 Dongdong LIU Zeyu WU Kaifeng SONG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第3期344-356,共13页
This study aims to investigate the output work and temperature drop in a compressor disk cavity equipped with a Finned Vortex Reducer(FVR)to improve the performance of the secondary air system of gas turbine engines.B... This study aims to investigate the output work and temperature drop in a compressor disk cavity equipped with a Finned Vortex Reducer(FVR)to improve the performance of the secondary air system of gas turbine engines.Based on the experimentally validated simulation results,we explore the effects of the rotating speed of the disk,coolant mass flow rate and the size of the fin on the flow and energy transfer of the radial inflow in the rotating cavity.The results show that the circumferential acceleration of the flow by Coriolis force is inhibited by the radial assembled fins from the rotating coordinate system,forcing the swirl ratio into one in the finned region and resulting in the reduction of the pressure drop.Outside the finned region,the variation characteristics of the swirl ratio follows that of a free vortex,which is typically found in the radial inflow through a simple cavity,i.e.,cavity without any vortex reducer.For the output work of the FVR cavity flow,it is mainly caused by the pressure difference on the fin surfaces,while those by the viscous shear force could be neglected.We propose a simplified model to predict the output work and total temperature change in the FVR cavity,which generally matches well with the simulation result.The research findings can provide guidance for the design and optimization of secondary air system in gas turbines. 展开更多
关键词 Finned vortex reducer Output work Radial inflow Swirl ratio Temperature drop
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Aqueous two-phase high-viscosity friction reducer for deep reservoir fracturing and its mechanisms of temperature resistance and viscosity enhancement 认领 引用
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作者 YOU Qing DING Xingxing +4 位作者 LI Hanzhou HUANG Xiaokai JIN Zhirong DAI Caili TAO Jiaping 《Petroleum Exploration and Development》 SCIE 2026年第3期875-886,共12页
Given the stringent requirements for friction reducers in terms of long-distance friction reduction,efficient proppant transport,temperature resistance and viscosity enhancement in deep oil and gas reservoir fracturin... Given the stringent requirements for friction reducers in terms of long-distance friction reduction,efficient proppant transport,temperature resistance and viscosity enhancement in deep oil and gas reservoir fracturing development,an aqueous two-phase high-viscosity friction reducer ANsD-PADA suitable for deep reservoir fracturing was prepared by introducing nanomaterial ANsD and through the aqueous two-phase polymerization.Its mechanisms of temperature resistance,viscosity enhancement,and friction reduction were explored by means of fluorescence spectroscopy,microscopic morphology observation,nanomechanical testing and other analytical methods,and field tests were also carried out.The introduction of hydrophobic monomer N-(3-dimethylaminopropyl)methacrylamide enables PADA(a self-synthesized hydrophobic terpolymer)molecules to entangle,associate and self-assemble into a honeycomb-like network structure under the combined effects of van der Waals forces,electrostatic repulsion and hydrophobic interaction.This structure further increases the hydrodynamic volume,thereby significantly improving the viscosity-enhancing performance of the product.ANsD fills the pores of the polymer network structure,effectively strengthening the network skeleton and association junctions,and remarkably improving the temperature resistance of the system.The friction reducer retains a friction reduction rate of 73.36%at 130°C,with a temperature resistance up to 150°C,and it has demonstrated encouraging results in the pilot site at Well XX-HF targeting deep shale oil reservoirs on the northern slope zone of the Gaoyou Sag,Subei Basin,China. 展开更多
关键词 deep oil and gas fracturing nanomaterial aqueous two-phase high-viscosity friction reducer temperature resistance viscosity enhancement nanomechanics
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High-temperature and high-salinity resistance hydrophobic association zwitterionic filtrate loss reducer for water-based drilling fluids 认领 引用 被引量：1
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作者 Tai-Feng Zhang Jin-Sheng Sun +5 位作者 Jing-Ping Liu Kai-He Lv Yuan-Wei Sun Zhe Xu Ning Huang Han Yan 《Petroleum Science》 SCIE EI CAS CSCD 2025年第7期2851-2867,共17页
As the global exploration and development of oil and gas resources advances into deep formations,the harsh conditions of high temperature and high salinity present significant challenges for drilling fluids.In order t... As the global exploration and development of oil and gas resources advances into deep formations,the harsh conditions of high temperature and high salinity present significant challenges for drilling fluids.In order to address the technical difficulties associated with the failure of filtrate loss reducers under high-temperature and high-salinity conditions.In this study,a hydrophobic zwitterionic filtrate loss reducer(PDA)was synthesized based on N,N-dimethylacrylamide(DMAA),2-acrylamido-2-methylpropane sulfonic acid(AMPS),diallyl dimethyl ammonium chloride(DMDAAC),styrene(ST)and a specialty vinyl monomer(A1).When the concentration of PDA was 3%,the FLAPI of PDA-WBDF was 9.8 mL and the FLHTHP(180℃,3.5 MPa)was 37.8 mL after aging at 240℃for 16 h.In the saturated NaCl environment,the FLAPI of PDA-SWBDF was 4.0 mL and the FLHTHP(180℃,3.5 MPa)was 32.0 mL after aging at 220℃ for 16 h.Under high-temperature and high-salinity conditions,the combined effect of anti-polyelectrolyte and hydrophobic association allowed PDA to adsorb on the bentonite surface tightly.The sulfonic acid groups of PDA increased the negative electronegativity and the hydration film thickness on bentonite surface,which enhanced the colloidal stability,maintained the flattened lamellar structure of bentonite and formed an appropriate particle size distribution,resulting in the formation of dense mud cakes and reducing the filtration loss effectively. 展开更多
关键词 High-temperature High-salinity Hydrophobic association Zwitterionic Filtrate loss reducer Water-based drilling fluids
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Experimental Investigation into the Impact of a Viscosity Reducer on the Crude Oil Recovery Rate in a Low-Permeability Reservoir 认领 引用
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作者 Baoyu Chen Meina Li +4 位作者 Jicheng Zhang Wenguo Ma YueqiWang Tianchen Pan Xuan Liu 《Fluid Dynamics & Materials Processing》 EI 2025年第6期1459-1471,共13页
The relative permeability of oil and water is a key factor in assessing the production performance of a reservoir.This study analyzed the impact of injecting a viscosity reducer solution into low-viscosity crude oil t... The relative permeability of oil and water is a key factor in assessing the production performance of a reservoir.This study analyzed the impact of injecting a viscosity reducer solution into low-viscosity crude oil to enhance fluid flow within a low-permeability reservoir.At 72°C,the oil-water dispersion solution achieved a viscosity reduction rate(f)of 92.42%,formulated with a viscosity reducer agent concentration(CVR)of 0.1%and an oil-water ratio of 5:5.The interfacial tension between the viscosity reducer solution and the crude oil remained stable at approximately 1.0 mN/m across different concentrations,with the minimum value of 4.07×10-1mN/m recorded at a CVRof 0.2%.As the CVR increased,the relative permeability curve of the oil phase gradually decreased while the oil-water two-phase region(Ro-wtp)expanded significantly.At a CVRof 0.1%,the Ro-wtppeaked,making an increase of 7.93 percentage points compared to water flooding.In addition,the final displacement efficiency(ER,final)achieved with a 0.1%viscosity reducer solution reached 48.64%,exceeding water flooding by 15.46 percentage points,highlighting the effectiveness of the viscosity reducer solution in enhancing oil recovery. 展开更多
关键词 Low-permeability reservoir low-viscosity crude oil viscosity reducer relative permeability oil displace-ment efficiency
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A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids 认领 引用 被引量：7
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作者 Jian Li Yu-Xi Ji +3 位作者 Xiao-Xiao Ni Kai-He Lv Xian-Bin Huang Jin-Sheng Sun 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1980-1991,共12页
During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtr... During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a challenge.Herein,a micro-crosslinked amphoteric hydrophobic association copolymer(i.e.,DADC)was synthesized using N,N-dimethyl acrylamide,diallyl dimethyl ammonium chloride,2-acrylamido-2-methylpropane sulfonic acid,hydrophobic monomer,and pentaerythritol triallyl ether crosslinker.Due to the synergistic effects of hydrogen bonds,electrostatic interaction,hydrophobic association,and micro-crosslinking,the DADC copolymer exhibited outstanding temperature-and salt-resistance.The rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing performance.The DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds,which bring more negative charge to the bentonite,thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling fluids.Moreover,the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP=12 m L)after aging at high temperatures(up to200℃)and high salinity(saturated salt)environments.Therefore,this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents,demonstrating good potential applications in deep and ultradeep drilling engineering. 展开更多
关键词 Fluid loss reducer Temperature-and salt-resistance Hydrophobic association Amphoteric Micro-crosslinking
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A high salt tolerance and low adsorption drag reducer based on non-covalent enhancement 认领 引用 被引量：4
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作者 MA Yingxian ZHU Zhi +4 位作者 GUO Jianchun ZHOU Han LI Jia XIONG Yujia MA Leyao 《Petroleum Exploration and Development》 SCIE 2020年第6期1333-1341,共9页
To formulate fluids with flowback water,produced water directly to improve the utilization rate of recycling and reduce the adsorption damage of slick water to reservoirs,a high salt tolerance and low adsorption drag ... To formulate fluids with flowback water,produced water directly to improve the utilization rate of recycling and reduce the adsorption damage of slick water to reservoirs,a high salt tolerance and low adsorption drag reducer was designed and prepared by introducing polar cation fragments to enhance the non-covalent interactions between the chains.The drag reducer was characterized by IR and NMR.Friction resistance and viscosity tests were conducted to evaluate its salt resistance property.Static adsorption and dynamic adsorption retention tests were carried out to evaluate the damage of this reducer to shale reservoirs.The introduction of cation units into the molecular structure can weak the shielding effect of metal cations to some extent,so the drag reducer can keep a stable molecular structure and good resistant reducing performance under high salinity.The enhancement of non-covalent interaction between chains decreased the free polarity sites,further reduced the possibility of hydrogen bonding between drag reducer molecules and shale.In high salinity condition,both the adsorption capacity of the drag reducer on the shale surface and the average damage rate to the core permeability are low.Compared with the conventional salt-tolerant system,the overall liquid cost was reduced by 17%and the production per well increased by 44%.The application of this slick water system has achieved remarkable results. 展开更多
关键词 shale hydraulic fracturing slick water drag reducer low adsorption high salt tolerance
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Design System of the Two-step Gear Reducer on Case-based Reasoning 认领 引用 被引量：7
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作者 JI Aimin HUANG Quansheng +1 位作者 XU Huanmin CHEN Zhengming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS 2009年第5期671-679,共9页
The design of the two-step gear reducer is a tedious and time-consuming process. For the purpose of improving the efficiency and intelligence of design process, case-based reasoning（CBR） technology was applied to th... The design of the two-step gear reducer is a tedious and time-consuming process. For the purpose of improving the efficiency and intelligence of design process, case-based reasoning（CBR） technology was applied to the design of the two-step gear reducer. Firstly, the current design method for the two-step gear reducer was analyzed and the principle of CBR was described. Secondly, according to the characteristics of the reducer, three key technologies of CBR were studied and the corresponding methods were provided, which are as follows： （a） an object-oriented knowledge representation method, （b） a retrieval method combining the nearest neighbor with the induction indexing, and （c） a case adaptation algorithm combining the revision based on rule with artificial revision. Also, for the purpose of improving the credibility of case retrieval, a new method for determining the weights of characteristics and a similarity formula were presented, which is a combinatorial weighting method with the analytic hierarchy process（AHP） and roughness set theory. Lastly, according to the above analytic results, a design system of the two-step gear reducer on CBR was developed by VC＋＋, UG and Access 2003. A new method for the design of the two-step gear reducer is provided in this study. If the foregoing developed system is applied to design the two-step gear reducer, design efficiency is improved, which enables the designer to release from the tedious design process of the gear reducer so as to put more efforts on innovative design. The study result fully reflects the feasibility and validity of CBR technology in the process of the design of the mechanical parts. 展开更多
关键词 two-step gear reducer case-based reasoning（CBR） weights of characteristics similarity
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基于ORC元数据的Hive Join查询Reducer负载均衡方法 认领 引用 被引量：3
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作者 王华进 黎建辉 +1 位作者 沈志宏 周园春 《计算机科学》 CSCD 北大核心 2018年第3期158-164,共7页
负载不均衡问题位列影响大规模MapReduce集群性能因素的首位,而Hive join查询非常容易触发该问题。通用解决方案是基于中间键值对的key频率分布设计能够实现负载均衡的key划分算法。现有工作估算key频率分布时依赖于对map的输出进行监... 负载不均衡问题位列影响大规模MapReduce集群性能因素的首位,而Hive join查询非常容易触发该问题。通用解决方案是基于中间键值对的key频率分布设计能够实现负载均衡的key划分算法。现有工作估算key频率分布时依赖于对map的输出进行监控采样,使得通信开销较大并显著延后了shuffle的启动。针对Hive join查询,提出了基于ORC元数据的key频率分布估计方法和相应的负载均衡key划分方法。该方法具有计算量小、通信开销小、不影响现有shuffle机制的优点。通过基准测试证明了该方法在key频率分布估算效率上的巨大提升及相应的key划分方法对Hive join查询性能的提升。 展开更多
关键词 负载均衡 MapReduce Hive Join Reducer ORC
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Load Sharing Behavior of Star Gearing Reducer for Geared Turbofan Engine 认领 引用 被引量：3
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作者 Shuai MO Yidu ZHANG +3 位作者 Qiong WU Feiming WANG Shigeki MATSUMURA Haruo HOUJOH 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期796-803,共8页
Load sharing behavior is very important for power-split gearing system, star gearing reducer as a new type and special transmission system can be used in many industry fields. However, there is few literature regardin... Load sharing behavior is very important for power-split gearing system, star gearing reducer as a new type and special transmission system can be used in many industry fields. However, there is few literature regarding the key multiple-split load sharing issue in main gearbox used in new type geared turbofan engine. Further mechanism anal- ysis are made on load sharing behavior among star gears of star gearing reducer for geared turbofan engine. Compre- hensive meshing error analysis are conducted on eccentricity error, gear thickness error, base pitch error, assembly error, and bearing error of star gearing reducer respectively. Floating meshing error resulting from meshing clearance variation caused by the simultaneous floating of sun gear and annular gear are taken into account. A refined mathematical model for load sharing coefficient calculation is established in consideration of different meshing stiffness and support- ing stiffness for components. The regular curves of load sharing coefficient under the influence of interactions, single action and single variation of various component errors are obtained. The accurate sensitivity of load sharing coefficienttoward different errors is mastered. The load sharing coef- ficient of star gearing reducer is 1.033 and the maximum meshing force in gear tooth is about 3010 N. This paper provides scientific theory evidences for optimal parameter design and proper tolerance distribution in advanced devel- opment and manufacturing process, so as to achieve optimal effects in economy and technology. 展开更多
关键词 Geared turbofan engine GTF engineAero-turbofan engine Star gearing reducer Load sharing behavior
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Method for optimizing manipulator's geometrical parameters and selecting reducers 认领 引用 被引量：4
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作者 杜志江 肖永强 董为 《Journal of Central South University》 SCIE EI CAS 2013年第5期1235-1244,共10页
A geometrical parameters optimization and reducers selection method was proposed for robotic manipulators design. The Lagrangian approach was employed in deriving the dynamic model of a two-DOF manipulator. The flexib... A geometrical parameters optimization and reducers selection method was proposed for robotic manipulators design. The Lagrangian approach was employed in deriving the dynamic model of a two-DOF manipulator. The flexibility of links and joints was taken into account in the mechanical structure dimensions optimization and reducers selection, in which Timoshenko model was used to discretize the hollow links. Two criteria, i.e. maximization of fundamental frequency and minimization of self-mass/load ratio, were utilized to optimize the manipulators. The NSGA-II (fast elitist nondominated sorting genetic algorithms) was employed to solve the multi-objective optimization problem. How the joints flexibility affects the manipulators design was analyzed and shown in the numerical analysis example. The results indicate that simultaneous consideration of the joints and the links flexibility is very necessary for manipulators optimal design. Finally, several optimal combinations were provided. The effectiveness of the optimization method was proved by comparing with ADAMS simulation results. The self-mass/load ratio error of the two methods is within 10%. The maximum error of the natural frequency by the two methods is 23.74%. The method proposed in this work provides a fast and effective pathway for manipulator design and reducers selection. 展开更多
关键词 robotic manipulator optimal design reducer selection flexible links flexible joints
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Syntheses and properties of associative acrylamide copolymers containing short hydrophobic chains used in a friction reducer for slick-water fracturing 认领 引用 被引量：2
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作者 Ya-Xing Dai Xian-Li Zhang +6 位作者 Si-Yuan Liu Feng-Run-Ze Zhang Yi-Xi Zhang Yu-Tong Sang Jing-Xi Zheng Zhao-Sheng Liu Peng Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1889-1901,共13页
Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacr... Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide materials.Two new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),respectively.The structures of the drag reduction agents were confirmed by IR and1H NMR spectroscopies.The molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×106g/mol.When the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×106g/mol.When the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,respectively.Compared with HPAM,both of the above copolymers presented better drag reduction capacities. 展开更多
关键词 Shale gas Slick water Drag reducer Modified monomer Copolymerization
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Mesh Force Modelling and Parametric Studies for Compound Oscillatory Roller Reducer 认领 引用 被引量：2
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作者 Changxu Wei Chaosheng Song +2 位作者 Caichao Zhu Chengcheng Liang Long Hu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第4期151-167,共17页
A compound oscillatory roller reducer(CORR)with a first-stage gear transmission and a second-stage oscillatory roller transmission is presented.The transmission principle of oscillatory roller transmission is introduc... A compound oscillatory roller reducer(CORR)with a first-stage gear transmission and a second-stage oscillatory roller transmission is presented.The transmission principle of oscillatory roller transmission is introduced,and the tooth profile equation of the inner gear is derived.The analytical model of mesh force considering the installation errors and manufacturing errors is proposed.Then,parametric studies considering different errors on the mesh force are conducted.Results show that the design parameters are significant factors for mesh force.The mesh force is reduced by 17%as the eccentricity of disk cam increases from 2.5 mm to 4 mm.When the radius of the movable roller increases from 7 mm to 20 mm,the mesh force decreases by 8%.As the radius of disk cam increases from 125 mm to 170 mm,the mesh force is decreased by 26.5%.For the impacts of errors,the mesh force has a noticeable fluctuation when these errors exist including the manufacturing error of disk cam,the installation error of disk cam and the manufacturing error of movable roller change.The prototype of the reducer is manufactured and preliminary run-in test proved the feasibility of the transmission principle. 展开更多
关键词 Compound oscillatory roller reducer Kinematic principle Mesh force modelling Misalignments Parametric study
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Belief reliability modeling and analysis for planetary reducer considering multi-source uncertainties and wear 认领 引用 被引量：2
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作者 LI Yun JIANG Kaige +4 位作者 ZENG Ting CHEN Wenbin LI Xiaoyang LI Deyong ZHANG Zhiqiang 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2021年第5期1246-1262,共17页
The planetary reducer is a common type of transmission mechanism,which can provide high transmission accuracy and has been widely used,and it is usually required with high reliability of transmission characteristics i... The planetary reducer is a common type of transmission mechanism,which can provide high transmission accuracy and has been widely used,and it is usually required with high reliability of transmission characteristics in practice.During the manufacturing and usage stages of planetary reducers,uncertainties are ubiquitous and wear is inevitable,which affect the transmission characteristics and the reliability of planetary reducers.In this paper,belief reliability modeling and analysis considering multi-uncertainties and wear are proposed for planetary reducers.Firstly,based on the functional principle and the influence of wear,the performance margin degradation model is established using the hysteresis error as the key performance parameter,where the degradation is mainly caused by the accumulated wear.After that,multi-source uncertainties are analyzed and quantified separately,including manufacturing errors,uncertainties in operational and environmental conditions,and uncertainties in performance thresholds.Finally,the belief reliability model is established based on the performance margin degradation model.A case study of a planetary reducer is applied and the reliability sensitivity analysis is implemented to show the practicability of the proposed method.The results show that the proposed method can provide some suggestions to the design and manufacturing phases of the planetary reducer. 展开更多
关键词 belief reliability planetary reducer performance margin wear multi-source uncertainty
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Design and Dynamics Simulation of a Novel Double-Ring-Plate Gear Reducer 认领 引用 被引量：3
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作者 张俊 宋轶民 张策 《Transactions of Tianjin University》 EI CAS 2007年第3期163-168,共6页
A patented double-ring-plate gear reducer was designed and its dynamic performance was simulated. One unique characteristic of this novel drive is that the phase angle difference between two parallelogram mechanisms i... A patented double-ring-plate gear reducer was designed and its dynamic performance was simulated. One unique characteristic of this novel drive is that the phase angle difference between two parallelogram mechanisms is a little less than 180 degree and four counterweights on two crankshafts are designed to balance inertia forces and inertia moments of the mechanisms. Its operating principle, advantages, and design issues were discussed. An elasto-dynamics model was presented to acquire its dynamic response by considering the elastic deformations of ring-plates, gears, bearings, etc. The simulation results reveal that compared with housing bearings, planetary bearings work in more severe conditions. The fluctuation of loads on gears and bearings indicates that the main reason for reducer vibration is elastic deformations of the system rather than inertia forces and inertia moments of the mechanisms. 展开更多
关键词 double-ring-plate gear reducer planetary transmission elasto-dynamics
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Reliability Analysis of Filtering Reducers Considering Temperature Correction and Shock Load of Space 认领 引用 被引量：1
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作者 ZHANG Xiaoqiang GAO Huiying +1 位作者 FU Guozhong HUANG Hongzhong 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第3期456-464,共9页
Owing to some excellent properties(such as large transmission ratio, high reliability, high precision,large stiffness, small volume and long service life), filtering reducers are suitable for occasions with high requi... Owing to some excellent properties(such as large transmission ratio, high reliability, high precision,large stiffness, small volume and long service life), filtering reducers are suitable for occasions with high requirements(e.g. space equipment). However, the tough working condition in space(including frequent changes of temperature, and large temperature difference combined with shock loads) may significantly affect the reliability.In this paper, the expressions of the minimal and maximal instantaneous transmission ratios(ITRs) considering temperature correction are developed. The minimal and maximal ITRs from simulation are used to verify the accuracy. Moreover, the reliability of a filtering reducer under different temperatures and the shock load are calculated, respectively. The research is beneficial to the design of spacecraft mechanism. 展开更多
关键词 reliability analysis filtering reducer temperature correction shock load
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Research on Transmission Accuracy Characteristic Analysis of RV Reducer 认领 引用 被引量：8
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作者 TAN Peng QI Houjun +2 位作者 HAN Lin FENG Juntao MA Dongsheng 《International Journal of Plant Engineering and Management》 2019年第3期157-168,共12页
The accuracy of RV reducer transmission is mainly affected by the transmission accuracy. Taking the high precision RV-80E reducer as the research object, aiming at its structural characteristics, the rigid-flexible co... The accuracy of RV reducer transmission is mainly affected by the transmission accuracy. Taking the high precision RV-80E reducer as the research object, aiming at its structural characteristics, the rigid-flexible coupling model of RV reducer is established by using ADAMS multi-body dynamics simulation software, and the correctness of the model is verified. At the same time, the rigid-flexible coupling model is used to design several groups of simulation prototypes with different errors, and the influence of different error factors on the transmission accuracy of the whole machine is analyzed by simulation. Finally, through different error factors, it is concluded that the error combination of positive equidistance+negative offset or negative equidistance+positive offset can effectively reduce the influence of transmission error on the transmission accuracy of the whole machine. 展开更多
关键词 RV reducer rigid-flexible coupling transmission error transmission accuracy
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Theoretical calculation and experimental study on the load distribution coefficient (LDC) of three-ring gear reducer 认领 引用 被引量：1
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作者 梁永生 李华敏 李瑰贤 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第6期748-752,共5页
In this paper, primary manufacturing and assembling errors of three-ring gear reducer （TRGR） are analyzed. TRGR is a new transmission type whose eccentric phase difference between middle ring plate and side ring pla... In this paper, primary manufacturing and assembling errors of three-ring gear reducer （TRGR） are analyzed. TRGR is a new transmission type whose eccentric phase difference between middle ring plate and side ring plates is 120°, Its mass of middle ring plate is equal to that of side ring plate or 180°, and its inass of middle ring plate is twice of that of side ring plate, which affects load distribution between ring plates. The primary manufacturing and assembling errors include eccentric error of eccentric sheath E111, internal gear plate E1 and output external gear E11. A new theoretical method is presented in this paper, which converts load on ring plates into the dedendum bending stress of ring plate to calculate load distribution coefficient （ LDC ）, by means of gap element method （GEM）, one of finite element method （FEM）. The theoretical calculation and experimental study, which measures ring plate dedendum bending stress by means of sticking strain gauges on the dedendum of middle ring plate internal gear and side ring plate internal gears, are presented. The theoretical calculation and comparison with experiment result of LDC are implemented an two kinds of three-ring gear reducers whose eccentric phase difference between eccentric sheaths is 120° and 180°respectively. The research indicates that the result of theoretical calculation is consistent with that of experimental study. That is to say, the theoretical calculation method is feasible. 展开更多
关键词 three-ring gear reducer （TRGR） load distribution coefficient （LDC） finite element method （FEM） gap element method （GEM）
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DYNAMICAL BALANCE STUDY OF RING REDUCER 认领 引用 被引量：2
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作者 Zhu Caichao Qin DatongState Key Laboratory ofMechanical Transmission,Chongqing University,Chongqing 400044, China 《Chinese Journal of Mechanical Engineering》 EI CAS 2003年第1期87-90,共4页
The basic structure of epicyclical gear transmission with inner teeth ofsingle-ring, double-ring, three-ring and four-ring reducer are analyzed. The force analysis model ofring reducer is built. Following this, it is ... The basic structure of epicyclical gear transmission with inner teeth ofsingle-ring, double-ring, three-ring and four-ring reducer are analyzed. The force analysis model ofring reducer is built. Following this, it is concluded that the present ring reducer~ have theproblem that the inertia force or the inertia moment is lopsided. On the base of analysis andcalculation the balanced ring reducer which can realize the balance of inertia force and inertiamoment is brought forward, and so is its concrete realizing step. The specimen of the balanced ringreducer is designed and manufactured; the experiment is carried out on the gear transmission testbench. Compared with other ring reducer of the same power, the balanced ring reducer has manyadvantages, such as low vibration noise, low cost and less production difficulty and less heat. Itis the substitute of other ring reducer of the same kind. Therefore, it has important theoreticsignificance and highly practical engineering value. 展开更多
关键词 Dynamical balance Reducer Vibration Noise
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Subsea Compensation of Pressure Based on Reducer Bellows 认领 引用
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作者 Shihong Xiao Shichao Zhou +2 位作者 Linlin Yue Xianyou He Maolin Xiang 《Fluid Dynamics & Materials Processing》 EI 2023年第10期2549-2567,共19页
In this study,the pressure compensation mechanism of a reducer bellows is analyzed.This device is typically used to reduce the size of undersea instruments and improve related pressure resistance and sealing capabilit... In this study,the pressure compensation mechanism of a reducer bellows is analyzed.This device is typically used to reduce the size of undersea instruments and improve related pressure resistance and sealing capabilities.Here,its axial stiffness is studied through a multi-fold approach based on theory,simulations and experiments.The results indicate that the mechanical strength of the reducer bellows,together with the oil volume and temperature are the main factors influencing its performances.In particular,the wall thickness,wave number,middle distance,and wave height are the most influential parameters.For a certain type of reducer bellows,the compensation capacity attains a maximum when the wave number ratio is between 6:6 and 8:4,the wall thickness is 0.3 mm,and the wave height is between 4–5 mm and 5–6 mm.Moreover,the maximum allowable ambient pres-sure of the optimized reducer bellows can reach 62.6 MPa without failure,and the maximum working water depth is 6284 m. 展开更多
关键词 Subsea reducer bellows pressure compensation compressible fluid mechanical strength
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Engineering Structure and Strength Design of Reducer Bend under Internal Pressure 认领 引用
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作者 CHEN Sun-Yi CHEN Jin LIU Ceng-dian 《International Journal of Plant Engineering and Management》 2016年第2期93-106,共14页
Standard reducer bends have structural functions of both bend and reducer pipe at the same time. However, there is a lack of strength design method in the current codes. In order to develop the strength design method ... Standard reducer bends have structural functions of both bend and reducer pipe at the same time. However, there is a lack of strength design method in the current codes. In order to develop the strength design method of the reducer bends subjected to internal pressure, analytical formulas are re-examined. Finite element analysis and stress measurements of the reducer bend are carried out. It is found that it is not appropriate to analyze the reducer bends by using thin membrane theory. The formula derived directly from circumferential stress formula of reducer bends under internal pressure is conservative, which is further verified by the finite element analysis results and it can thus be applied to piping design. 展开更多
关键词 strength design stress analysis reducer pipe reducer bends elbows
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