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Exact Solutions of Schr¨odinger Equation with Improved Ring-Shaped Non-Spherical Harmonic Oscillator and Coulomb Potential
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作者 Akpan Ndem Ikot Ita O.Akpan +1 位作者 T.M.Abbey Hassan Hassanabadi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第5期569-574,共6页
We propose improved ring shaped like potential of the form,V(r,θ)=V(r)+(h^2/2M r^2)[(βsin^2θ+γcos^2θ+2λ)/sinθcosθ]^2 and its exact solutions are presented via the Nikiforov–Uvarov method.The angle ... We propose improved ring shaped like potential of the form,V(r,θ)=V(r)+(h^2/2M r^2)[(βsin^2θ+γcos^2θ+2λ)/sinθcosθ]^2 and its exact solutions are presented via the Nikiforov–Uvarov method.The angle dependent part V(θ)=(h^2/2M r^2)[(βsin^2θ+γcos^2θ+λ)/sinθcosθ]^2,which is reported for the first time embodied the novel angle dependent(NAD)potential and harmonic novel angle dependent potential(HNAD)as special cases.We discuss in detail the effects of the improved ring shaped like potential on the radial parts of the spherical harmonic and Coulomb potentials. 展开更多
关键词 improved ring shaped like potential Schr¨odinger equation Nikiforov–Uvarov method
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Exact solutions of the Dirac equation with Pschl-Teller double-ring-shaped Coulomb potential via the Nikiforov-Uvarov method 被引量:2
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作者 E.Maghsoodi H.Hassanabadi S.Zarrinkamar 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期117-121,共5页
Exact analytical solutions of the Dirac equation are reported for the Poschl-Teller double-ring-shaped Coulomb potential.The radial,polar,and azimuthal parts of the Dirac equation are solved using the Nikiforov-Uvarov... Exact analytical solutions of the Dirac equation are reported for the Poschl-Teller double-ring-shaped Coulomb potential.The radial,polar,and azimuthal parts of the Dirac equation are solved using the Nikiforov-Uvarov method,and the exact bound-state energy eigenvalues and corresponding two-component spinor wavefunctions are reported. 展开更多
关键词 Dirac equation Poschl-Teller double-ring-shaped Coulomb potential Nikiforov-Uvarov method
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Deformation Analysis on Shear-Bending of Ring-Shaped Piezoelectric Actuator
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作者 康新 董帅 何小元 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第6期585-590,共6页
Deformation of a simple single piezoelectric actuator is usually quite small.A ring-shaped piezoelectric actuator with large piezoelectrically generated displacement was proposed.The thickness of the actuator was1 mm,... Deformation of a simple single piezoelectric actuator is usually quite small.A ring-shaped piezoelectric actuator with large piezoelectrically generated displacement was proposed.The thickness of the actuator was1 mm,and the inner and outer diameters were 4 mm and 40 mm,respectively.The ring-shaped actuator was made of BiScO_3-PbTiO_3(BS-PT)ceramic and polarized in radial direction.An electric field was applied to thickness direction and a large shear-bending deformation emerged.Then Rayleigh-Ritz method and Bessel functions were adopted to analyze the shear-bending deformation.Results show that under an electric field of 7.5kV/cm,the maximum displacement at the inner edge of the actuator reached 5.07μm,which agreed well with the corresponding experimental results. 展开更多
关键词 ring-shaped piezoelectric actuator shear-bending Rayleigh-Ritz method
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Formation Mechanism of the Ring-shaped Structure of Plasma Bullet
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作者 YAN Wen LIU Fucheng WANG Dezhen 《高电压技术》 EI CAS CSCD 北大核心 2013年第9期2309-2316,共8页
The formation of plasma bullets’ring-shaped structure in atmospheric pressure helium is analyzed by using a coupled fluid model.The model consists of a two-dimension neutral gas flow module and a one-dimension plasma... The formation of plasma bullets’ring-shaped structure in atmospheric pressure helium is analyzed by using a coupled fluid model.The model consists of a two-dimension neutral gas flow module and a one-dimension plasma dynamics module.The obtained radial distributions of the electron’s number density and the nitrogen’s metastable number density have different structures under different types of reactions or air contents in the model.It shows that total electron impact ionization plays an important role in sustaining the discharge,and together with Penning process,they lead to the shifted-off structure of electron number density.Meanwhile,the ring structure of plasma bullets forms mainly due to the excitation reaction of nitrogen molecule on air contents. 展开更多
关键词 氦等离子体 环形结构 形成机理 子弹 电子数密度 等离子体动力学 环状结构 控制模块
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Exact solutions of the Klein-Gordon equation with ring-shaped oscillator potential by using the Laplace integral transform
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作者 Sami Ortakaya 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期108-112,共5页
We present exact solutions for the Klein Gordon equation with a ring-shaped oscillator potential. The energy eigenvalues and the normalized wave functions are obtained for a particle in the presence of non-central osc... We present exact solutions for the Klein Gordon equation with a ring-shaped oscillator potential. The energy eigenvalues and the normalized wave functions are obtained for a particle in the presence of non-central oscillator potential. The angulm" functions are expressed in terms of the hypergeometric functions. The radial eigenfunetions have been obtained by using the Laplace integral transform. By means of the Laplace transform method, which is efficient and simple, the radial Klein-Gordon equation is reduced to a first-order differential equation. 展开更多
关键词 ring-shaped oscillator Klein-Gordon equation Laplace integral transform bound states
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The relativistic bound states for a new ring-shaped harmonic oscillator
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作者 周燕 郭建友 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期380-384,共5页
In this paper a new ring-shaped harmonic oscillator for spin 1/2 particles is studied, and the corresponding eigenfunctions and eigenenergies are obtained by solving the Dirac equation with equal mixture of vector and... In this paper a new ring-shaped harmonic oscillator for spin 1/2 particles is studied, and the corresponding eigenfunctions and eigenenergies are obtained by solving the Dirac equation with equal mixture of vector and scalar potentials. Several particular cases such as the ring-shaped non-spherical harmonic oscillator, the ring-shaped harmonic oscillator, non-spherical harmonic oscillator, and spherical harmonic oscillator are also discussed. 展开更多
关键词 new ring-shaped harmonic oscillator bound state Dirac equation
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The spin-one Duffin Kemmer Petiau equation in the presence of pseudo-harmonic oscillatory ring-shaped potential
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作者 H.Hassanabadi M.Kamali Physics 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期107-111,共5页
The Duffin-Kemmer-Petiau equation (DKP) is studied in the presence of a pseudo-harmonic oscillatory ring-shaped potential in (1 + 3)-dimensional space-time for spin-one particles. The exact energy eigenvalues and... The Duffin-Kemmer-Petiau equation (DKP) is studied in the presence of a pseudo-harmonic oscillatory ring-shaped potential in (1 + 3)-dimensional space-time for spin-one particles. The exact energy eigenvalues and the eigenfunctions are obtained using the Nikiforov-Uvarov method. 展开更多
关键词 DKP equation pseudo-harmonic oscillatory ring-shaped potential Nikiforov-Uvarov method en-ergy eigenvalues eigenfunctions
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Bound states of the Schrdinger equation for the Pschl-Teller double-ring-shaped Coulomb potential
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作者 陆法林 陈昌远 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期88-93,共6页
Poschl-Teller double-ring-shaped Coulomb (PTDRSC) potential, the Coulomb potential surrounded by PSschl- Teller and double-ring-shaped inversed square potential, is put forward. In spherical polar coordinates, PTDRS... Poschl-Teller double-ring-shaped Coulomb (PTDRSC) potential, the Coulomb potential surrounded by PSschl- Teller and double-ring-shaped inversed square potential, is put forward. In spherical polar coordinates, PTDRSC potential has supersymmetry and shape invariance in φ,θ and τ coordinates. By using the method of supersymmetry and shape invariance, exact bound state solutions of Schr6dinger equation with PTDRSC potential are presented. The normalized φ,θ angular wave function expressed in terms of Jacobi polynomials and the normalized radial wave function expressed in terms of Laguerre polynomials are presented. Energy spectrum equations are obtained. Wave function and energy spectrum equations of the system are related to three quantum numbers and parameters of PTDRSC potential. The solutions of wave functions and corresponding eigenvalues are only suitable for the PTDRSC potential. 展开更多
关键词 Poschl-Teller double-ring-shaped Coulomb potential supersymmetry and shape invari-ance Schrodinger equation bound states
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Analytic solutions of the double ring-shaped Coulomb potential in quantum mechanics
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作者 陈昌远 陆法林 +1 位作者 孙东升 董世海 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期94-100,共7页
The exact solutions of the Schr6dinger equation with the double ring-shaped Coulomb potential are presented, including the bound states, continuous states on the "k/2π scale", and the calculation formula of the pha... The exact solutions of the Schr6dinger equation with the double ring-shaped Coulomb potential are presented, including the bound states, continuous states on the "k/2π scale", and the calculation formula of the phase shifts. The polar angular wave functions are expressed by constructing the so-called super-universal associated Legendre polynomials. Some special cases are discussed in detail. 展开更多
关键词 double ring-shaped Coulomb potential super-universal associated-Legendre polynomial functional analysis method
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AERODYNAMIC ANALYSIS OF CIRCULAR PLATE-SHAPED AND CIRCULAR RING-SHAPED SQUEEZE FILM BEARINGS
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作者 姚德良 傅仙罗 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第8期759-766,共8页
Aerodynamics of circular plate- and circular ring-shaped squeeze film hearings is analyzed in detail, yielding analytic expressions for the pressure distribution of these hearings. Several formulae for these hearings ... Aerodynamics of circular plate- and circular ring-shaped squeeze film hearings is analyzed in detail, yielding analytic expressions for the pressure distribution of these hearings. Several formulae for these hearings are modified using the developed method. The paper also gives numerical results oj pressure distribution and load-hearing capacities of these hearings. 展开更多
关键词 circular ring-shaped circular plate-shaped squeeze film bearing
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STUDY ON THE RING SPINNING SYSTEM WITH A FIXED BELL SHAPED BALLOON CONTROLLER
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作者 刘玉军 陈明 刘春红 《Journal of China Textile University(English Edition)》 EI CAS 1996年第2期56-61,共6页
On the basis of analyzing the typical kinds of balloon controllers used now, this article provides a new type one named Fixed Bell Shaped Balloon Controller. Experiments have been made to verify the function of it. Re... On the basis of analyzing the typical kinds of balloon controllers used now, this article provides a new type one named Fixed Bell Shaped Balloon Controller. Experiments have been made to verify the function of it. Results indicated that the facility has quite good effect on the improvement of yarn quality and properties in addition to controlling yarn tension. 展开更多
关键词 ring SPINNING bell-shaped CONTROLLER BALLOON control
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The Calibration and Use of a New Ring-Shaped Ionization Chamber for Monitoring and Dosimetry of X-Ray Beams
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作者 Babak Sharifi Hossein Zamani Zeinali +2 位作者 Anita Alipoor Arjang Shahvar Ali Negarestani 《World Journal of Nuclear Science and Technology》 2015年第3期200-207,共8页
Today, dosimeters are used generally for dosimetry of the diagnostic X-ray beam. Ionization chambers are appropriate instruments for monitoring and also the dosimetry of X-ray beam in medical diagnostic equipment. The... Today, dosimeters are used generally for dosimetry of the diagnostic X-ray beam. Ionization chambers are appropriate instruments for monitoring and also the dosimetry of X-ray beam in medical diagnostic equipment. The present work introduces design and investigation of a new ring-shaped monitor chamber with a PMMA body, graphite-coated PMMA windows (0.5 mm thick), a special graphite-foil central electrode (0.1 mm thick, 0.7 g/cm3 dense) that creating two sensitive volumes and a central hole for crossing the radiation beam with less attenuation. The results of performance tests conducted at the Nuclear Science and Technology Research Institute, AEOI in Karaj- Iran proved the high short and long-term stability, the very low leakage current, the low directional dependence and very high ion collection efficiency through the special design of the collecting electrode. Moreover, the FLUKA Monte Carlo simulations certified the negligible effect of central electrode on this new ring-shaped monitor chamber. According to the results of the performance tests, the new monitor chamber can be used as a standard dosimeter in order to monitor X-ray beam in primary standard dosimetry laboratories. 展开更多
关键词 ring-shaped Monitor CHAMBER Diagnostic X-RAY Beam Quality Control Tests Low DENS Graphite-Foil Central Electrode
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Advances in Compact Manufacturing for Shape and Performance Controllability of Large-scale Components-A Review 被引量:4
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作者 QIN Fangcheng LI Yongtang +1 位作者 QI Huiping JU Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第1期7-21,共15页
Research on compact manufacturing technology for shape and performance controllability of metallic components can reanze the simplification and high-reliability of manufacturing process on the premise of satisfying th... Research on compact manufacturing technology for shape and performance controllability of metallic components can reanze the simplification and high-reliability of manufacturing process on the premise of satisfying the requirement of macro/micro-structure. It is not only the key paths in improving performance, saving material and energy, and green manufacturing of components used in major equipments, but also the challenging subjects in frontiers of advanced plastic forming. To provide a novel horizon for the manufacturing in the critical components is significant. Focused on the high-performance large-scale components such as bearing rings, flanges, railway wheels, thick-walled pipes, etc, the conventional processes and their developing situations are summarized. The existing problems including multi-pass heating, wasting material and energy, high cost and high-emission are discussed, and the present study unable to meet the manufacturing in high-quality components is also pointed out. Thus, the new techniques related to casting-rolling compound precise forming of rings, compact manufacturing for duplex-metal composite rings, compact manufacturing for railway wheels, and casting-extruding continuous forming of thick-walled pipes are introduced in detail, respectively. The corresponding research contents, such as casting ring blank, hot ring rolling, near solid-state pressure forming, hot extruding, are elaborated. Some findings in through-thickness microstructure evolution and mechanical properties are also presented. The components produced by the new techniques are mainly characterized by fine and homogeneous grains. Moreover, the possible directions for fin'ther development of those techniques are suggested. Finally, the key scientific problems are first proposed. All of these results and conclusions have reference value and guiding significance for the integrated control of shape and performance in advanced compact manufacturing. 展开更多
关键词 compact manufacturing shape and performance controllability HIGH-PERFORMANCE ring parts thick-walled pipes
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Electronic states of InAs/GaAs tyre-shape quantum ring
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作者 王传道 杨富华 封松林 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期3054-3057,共4页
In the framework of the effective mass theory, this paper calculates the electron energy levels of an InAs/GaAs tyre-shape quantum ring (TSQR) by using the plane wave basis. The results show that the electron energy... In the framework of the effective mass theory, this paper calculates the electron energy levels of an InAs/GaAs tyre-shape quantum ring (TSQR) by using the plane wave basis. The results show that the electron energy levels axe sensitively dependent on the TSQR's section thickness d, and insensitively dependent on TSQR's section inner radius R1 and TSQR's inner radius R2. The model and results provide useful information for the design and fabrication of InAs/GaAs TSQRs. 展开更多
关键词 tyre-shape quantum ring (TSQR) plan wave energy level
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GENERAL SOLUTION FOR U-SHAPED BELLOWS OVERALL-BENDING PROBLEMS 被引量:4
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作者 朱卫平 郭平 黄黔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第4期371-382,共12页
The formulae for stresses and angular displacements of U-shaped bellows overall bending in a meridian plane under pure bending moments are presented based on the general solution for slender ring shells proposed by Zh... The formulae for stresses and angular displacements of U-shaped bellows overall bending in a meridian plane under pure bending moments are presented based on the general solution for slender ring shells proposed by Zhu Weiping, et al. and the solution for ring plates. The results evaluated in this paper are compared with those on EJMA (standards of the expansion joint manufacturers association) and of the experiment given by Li Tingxilz, et al. 展开更多
关键词 flexible shells shells of revolution circular ring shells BELLOWS U-shaped bellows
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Nonlinear mechanics of a ring structure subjected to multi-pairs of evenly distributed equal radial forces 被引量:1
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作者 Q. Chen F. Sun +2 位作者 Z. Y. Li L. Taxis N. Pugno 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第5期942-953,共12页
Combining the elastica theory, finite element (FE) analysis, and a geometrical topological experiment, we studied the mechanical behavior of a ring subjected to multi-pairs of evenly distributed equal radial forces by... Combining the elastica theory, finite element (FE) analysis, and a geometrical topological experiment, we studied the mechanical behavior of a ring subjected to multi-pairs of evenly distributed equal radial forces by looking at its seven distinct states. The results showed that the theoretical predictions of the ring deformation and strain energy matched the FE results very well, and that the ring deformations were comparable to the topological experiment. Moreover, no matter whether the ring was compressed or tensioned by N-pairs of forces, the ring always tended to be regular polygons with 2N sides as the force increased, and a proper compressive force deformed the ring into exquisite flower-like patterns. The present study solves a basic mechanical problem of a ring subjected to lateral forces, which can be useful for studying the relevant mechanical behavior of ring structures from the nano- to the macro-scale. 展开更多
关键词 ring structures Mechanical properties shape Strain energy
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SYNTHESIS,CHARACTERIZATION AND NANOPARTICLE FORMATION OF STAR-SHAPED POLY(L-LACTIDE)WITH SIX ARMS 被引量:1
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作者 董常明 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第2期161-169,共9页
Well-defined star-shaped poly(L-lactide)with six arms(sPLLA)was synthesized via the ring-opening polymerization of L-lactide using dipentaerythritol as initiator and stannous octoate as catalyst in bulk at 125~C.The e... Well-defined star-shaped poly(L-lactide)with six arms(sPLLA)was synthesized via the ring-opening polymerization of L-lactide using dipentaerythritol as initiator and stannous octoate as catalyst in bulk at 125~C.The effects of molar ratios of both monomer to initiator and monomer to catalyst on the molecular weights of as-synthesized sPLLA polymers were in detail investigated.The molecular weights of sPLLA polymers linearly increased with the molar ratio of monomer to initiator,and the molecular weight dist... 展开更多
关键词 Star-shaped poly(L-Lactide) ring-opening polymerization Nanoparticles Drug delivery.
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Vertically stacked all-organic ring-shaped pulse oximetry sensor with ultra-low power consumption and low-luminance operation
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作者 Dongho Choi Seunghee Lee +5 位作者 Hyeonwoo Lee Ramakant Sharma Junho Kim Woochan Lee Jaehyeok Park Seunghyup Yoo 《npj Flexible Electronics》 2025年第1期1615-1624,共10页
Health monitoring with wearable pulse oximetry(PO)paves the way for personalized,point-of-care health management.Organic PO(OPO)sensors are particularly promising for wearable POs due to their excellent compatibility ... Health monitoring with wearable pulse oximetry(PO)paves the way for personalized,point-of-care health management.Organic PO(OPO)sensors are particularly promising for wearable POs due to their excellent compatibility with flexible,lightweight form factors and design freedom,enabling low power consumption comparable to or even surpassing that of conventional inorganic systems.However,further power reductions are crucial for wearable systems with limited onboard power,and achieving sufficient signal strength at minimal luminance is essential for extended operation.Here,we propose an OPO structure with both ultralow power consumption and low luminance operation.By combining a ring-shaped,vertically stacked two-color organic light-emitting diode(OLED)with a circular organic photodiode(OPD)filling the interior and exterior of the OLED ring,we demonstrate OPO sensors requiring only a fewμW to drive the OLEDs and operable at a few tens of cd/m^(2),demonstrating potentials for continuous health monitoring with extended long-term operation. 展开更多
关键词 health monitoring wearable pos low power consumption ring shaped vertically stacked power reductions wearable systems pulse oximetry
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V形金属密封环密封性能研究与优化
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作者 李卫民 唐兆庆 +2 位作者 张彦鹏 杨泽宇 宋明林 《机床与液压》 北大核心 2025年第11期158-166,共9页
针对某型发动机排气系统的法兰连接密封问题,提出一种V形金属密封环,研究V形金属密封环在多种工况下的密封特性。通过压缩回弹试验,得到V形金属密封环的压缩量与施加载荷之间的关系,进一步分析在常温及高温工况下,压缩量对密封性能的影... 针对某型发动机排气系统的法兰连接密封问题,提出一种V形金属密封环,研究V形金属密封环在多种工况下的密封特性。通过压缩回弹试验,得到V形金属密封环的压缩量与施加载荷之间的关系,进一步分析在常温及高温工况下,压缩量对密封性能的影响,从而确定合适的轴向压缩范围。结合有限元分析,研究壁厚、波谷半径、接触圆半径、环宽以及开口角度等5个参数对密封性能的影响。基于Box-Behnken试验设计构建响应面模型,采用多目标遗传算法优化结构参数。基于Design-Expert软件对V形环结构进行多目标优化,并对优化后的结构可靠性进行了验证。结果表明:结构参数对密封性能具有显著影响,最大等效应力与开口角度、波谷半径和壁厚呈正相关,与接触圆半径成反比,最大接触压力与波谷半径、壁厚呈正相关,与开口角度、接触圆半径和环宽成反比;优化后,最大等效应力下降了1.3%,最大接触压力增加了23.6%。 展开更多
关键词 V形金属密封环 压缩回弹性能 多目标优化设计 汽车排气系统
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V型弹簧蓄能密封圈低温工况密封特性仿真分析
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作者 吴斌 刘庆胜 +2 位作者 梁海雅 于金伟 朱东风 《石油化工设备》 2025年第6期27-34,共8页
针对液化天然气(LNG)卸料臂关键密封元件在低温工况下的性能需求,建立了V型弹簧蓄能密封圈等效二维轴对称有限元模型,对比分析了其在25℃常温与-162℃低温工况下的密封特性。结果表明,低温导致密封夹套材料弹性模量增大、韧性降低,引发... 针对液化天然气(LNG)卸料臂关键密封元件在低温工况下的性能需求,建立了V型弹簧蓄能密封圈等效二维轴对称有限元模型,对比分析了其在25℃常温与-162℃低温工况下的密封特性。结果表明,低温导致密封夹套材料弹性模量增大、韧性降低,引发显著的热收缩效应和非均匀温度场,进而使V型弹簧蓄能密封圈最大Mises应力增加20%、塑性形变峰值剧增100%以上、界面滑移距离锐减至70%~80%,增大了塑性累积损伤、脆性开裂与界面卡滞的失效风险。等效弹簧厚度在0.38~0.40 mm、介质压力在0.5~1.1 MPa、摩擦因数控制在0.10~0.12时,可有效抑制低温应力波动并维持较高的接触压力,降低塑性损伤风险。研究结果可为LNG低温设备V型弹簧蓄能密封圈的设计与优化提供参考。 展开更多
关键词 V型弹簧蓄能密封圈 有限元模型 低温工况 密封特性
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