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2-complex Symmetric Weighted Composition Operators on Fock Space of C^(N)
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作者 JIANG Zhijie 《数学进展》 北大核心 2025年第1期37-49,共13页
The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(... The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(■,...,■),t∈C,b∈C^(N) and A is a linear operator on C^(N).An example of 2-complex symmetric bounded weighted composition operator with the conjugation J_(t,A,b) is given. 展开更多
关键词 Fock space weighted composition operator 2-complex symmetric operator reproducing kernel function
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基于K-means与2-Opt改进的贪心路径优化算法研究 被引量:1
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作者 黄启华 冯子俊 +1 位作者 杜玉晓 王烁哲 《自动化与信息工程》 2025年第2期9-17,共9页
针对当前衣物裁剪路径优化算法无法同时满足高精度和低时间消耗的问题,提出基于K-means与2-Opt改进的贪心路径优化算法。首先,利用K-means聚类算法进行大规模旅行商问题的局部分组;然后,采用2-Opt改进的贪心算法优化路径;最后,通过最近... 针对当前衣物裁剪路径优化算法无法同时满足高精度和低时间消耗的问题,提出基于K-means与2-Opt改进的贪心路径优化算法。首先,利用K-means聚类算法进行大规模旅行商问题的局部分组;然后,采用2-Opt改进的贪心算法优化路径;最后,通过最近邻连接方法对子问题的解进行类间连接。实验结果验证了该算法具有较好的路径和效率优化能力。 展开更多
关键词 衣物裁剪路径优化 K-MEANS聚类算法 2-opt算法 贪心算法
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利用融合2-opt的强化学习算法求解TSP问题
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作者 彭俊龙 范静 《计算机科学》 北大核心 2025年第S2期170-177,共8页
旅行售货商问题(Traveling Salesman Problem,TSP)是运筹学中经典的组合优化问题,属于NP难问题。问题的目标是求解旅行商的环游路径,使其在经过每个城市一次后返回起点且路径长度最短。为求解此问题,提出基于指针网络的深度强化学习算法... 旅行售货商问题(Traveling Salesman Problem,TSP)是运筹学中经典的组合优化问题,属于NP难问题。问题的目标是求解旅行商的环游路径,使其在经过每个城市一次后返回起点且路径长度最短。为求解此问题,提出基于指针网络的深度强化学习算法(2+HRL),融合了2-opt算法和图注意力模型。使用图注意力网络提取城市节点的局部和全局结构信息,运用双向LSTM进行路径信息提取,期间利用2-opt策略,通过局部交换改进路径;进而使用REINFORCE算法进行策略网络的梯度优化,结合熵奖励函数避免陷入局部最优解,使用值函数对评价网络参数进行改进。实验结果证明,2+HRL优于传统启发式算法和精确算法,而且与一些深度强化学习算法相比较时,在较低的训练次数下,2+HRL具有更快的计算速度,更准确的计算精度;在增加训练次数后,模型的优化效果也超越了相比较的其他深度强化学习算法。 展开更多
关键词 图注意力网络 旅行售货商问题 深度强化学习 2-opt 组合最优化
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GENERALIZED OPERATORS AND P(φ)_2 QUANTUM FIELDS 被引量:1
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作者 黄志远 让光林 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期589-596,共8页
In this paper by Sobolev imbedding theorem and characterization theorem of generalized operators the existence of P(φ)2 quantum fields as generalized operators is obtained and a rigorous mathematical interpretation o... In this paper by Sobolev imbedding theorem and characterization theorem of generalized operators the existence of P(φ)2 quantum fields as generalized operators is obtained and a rigorous mathematical interpretation of renormalization procedure is given under white noise theory. 展开更多
关键词 White noise calculus generalized operator P(φ)2 quantum fields
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THE EXISTENCE AND BLOW-UP OF THE RADIAL SOLUTIONS OF A(k_(1),k_(2))-HESSIAN SYSTEM INVOLVING A NONLINEAR OPERATOR AND GRADIENT 被引量:1
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作者 Guotao WANG Zedong YANG +1 位作者 Jiafa XU Lihong ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第4期1414-1426,共13页
In this paper,we are concerned with the existence of the positive bounded and blow-up radial solutions of the(k1,k2)-Hessian system■where G is a nonlinear operator,Ki=Ski(λ(D^(2) z_(i)))+ψ_(i)(|x|)|▽_(zi)|^(ki),i=... In this paper,we are concerned with the existence of the positive bounded and blow-up radial solutions of the(k1,k2)-Hessian system■where G is a nonlinear operator,Ki=Ski(λ(D^(2) z_(i)))+ψ_(i)(|x|)|▽_(zi)|^(ki),i=1,2.Under the appropriate conditions on gi and g2,our main results are obtained by using the monotone iterative method and the Arzela-Ascoli theorem.Furthermore,our main results also extend the previous existence results for both the single equation and systems. 展开更多
关键词 (k_(1) k_(2))-Hessian system nonlinear operator BLOW-UP monotone iterative method GRADIENT
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Tailoring the number of lines for IGO-channel 2T0C DRAM comparable to conventional 2-line operation 1T1C structure for highly scaled cell volume
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作者 Jae-Hyeok Kwag Su-Hwan Choi +5 位作者 Daejung Kim Jun-Yeoub Lee Taewon Hwang Hye-Jin Oh Chang-Kyun Park Jin-Seong Park 《International Journal of Extreme Manufacturing》 2025年第5期404-414,共11页
Capacitor-less 2T0C dynamic random-access memory(DRAM)employing oxide semiconductors(OSs)as a channel has great potential in the development of highly scaled three dimensional(3D)-structured devices.However,the use of... Capacitor-less 2T0C dynamic random-access memory(DRAM)employing oxide semiconductors(OSs)as a channel has great potential in the development of highly scaled three dimensional(3D)-structured devices.However,the use of OS and such device structures presents certain challenges,including the trade-off relationship between the field-effect mobility and stability of OSs.Conventional 4-line-based operation of the 2T0C enlarges the entire cell volume and complicates the peripheral circuit.Herein,we proposed an IGO(In-Ga-O)channel 2-line-based 2T0C cell design and operating sequences comparable to those of the conventional Si-channel 1 T1C DRAM.IGO was adopted to achieve high thermal stability above 800℃,and the process conditions were optimized to simultaneously obtain a high μFE of 90.7 cm^(2)·V^(-)1·s^(-1),positive Vth of 0.34 V,superior reliability,and uniformity.The proposed 2-line-based 2T0C DRAM cell successfully exhibited multi-bit operation,with the stored voltage varying from 0 V to 1 V at 0.1 V intervals.Furthermore,for stored voltage intervals of 0.1 V and 0.5 V,the refresh time was 10 s and 1000 s in multi-bit operation;these values were more than 150 and 15000 times longer than those of the conventional Si channel 1T1C DRAM,respectively.A monolithic stacked 2-line-based 2T0C DRAM was fabricated,and a multi-bit operation was confirmed. 展开更多
关键词 capacitor-less 2T0C DRAM cell design and operation atomic layer deposition oxide semiconductor monolithic stacked
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New 3-mode bosonic operator realization of SU(2) Lie algebra:From the point of view of squeezing
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作者 笪诚 陈千帆 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期62-64,共3页
We consider the quantum mechanical SU(2) transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU(2) operators (J±,... We consider the quantum mechanical SU(2) transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU(2) operators (J±, Jz) from the point of view of squeezing we find that (J±,Jz) can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation (the eigenvectors of J+ or J-) of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU(2) transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU(2) and new squeezing operators. 展开更多
关键词 quantum mechanical SU(2 transformation 3-mode squeezing operator new 3-mode bosonic op-erator realization of SU(2 Lie algebra
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2-12寸碳钢管线生产线OPER1组对平台1常见电气故障解决
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作者 陈扬 郭宝桐 +1 位作者 宋梓昂 何维 《中国修船》 2025年第2期30-32,共3页
文章介绍了2-12寸碳钢管线生产线OPER1组对平台1的功能,即通过2-12寸碳钢管线生产线OPER1组对平台1保证管件在组对时的垂直度和同心度。对其常见的上升电气故障和前进电气故障的现象进行了分析,并提出了故障的解决方法。
关键词 2-12寸碳钢管线 oper1组对平台1 CPU模块 输入模块 交换机
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The Properties of the Shear Gradient Operator and Its Application in Image Deblurring
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作者 LIU Xiaofeng LU Lixuan ZHANG Tao 《Wuhan University Journal of Natural Sciences》 2025年第5期427-440,共14页
The utilization of gradient operators is prevalent in image processing,as they effectively detect edges and provide directional information.However,these operators only differentiate the horizontal and vertical direct... The utilization of gradient operators is prevalent in image processing,as they effectively detect edges and provide directional information.However,these operators only differentiate the horizontal and vertical directions,ignoring details and causing loss of informa-tion in other directions.This paper introduces the shear gradient operator to overcome this limitation by capturing details accurately in mul-tiple directions.It investigates the properties of the shear gradient operator and proposes the shear total variation(STV)norm for image de-blurring.By combining non-convex regularization to avoid excessive penalty and retain image details,a novel deblurring model integrat-ing the STV norm and the L1/L2 minimization is proposed.The alternating direction method of multipliers(ADMM)algorithm is employed to solve this computationally challenging model,demonstrating exceptional performance in non-blind image deblurring through experi-ments. 展开更多
关键词 shear gradient operator shear total variation norm image deblurring alternating direction method of multipliers(ADMM) L1/L2 minimization
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Projection Operator on Rational Noncommutative Orbifold T^2/Z_4
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作者 冯俊 杨战营 +2 位作者 张凯 侯伯宇 石康杰 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期107-118,共12页
In this paper, we introduce the reduced matrix in kq representation and provide the reduced matrix elements of a projection operator P on the rational noncommutative orbifold T^2/Z_4.we give the closed form for the pr... In this paper, we introduce the reduced matrix in kq representation and provide the reduced matrix elements of a projection operator P on the rational noncommutative orbifold T^2/Z_4.we give the closed form for the projector by Jacobi elliptical functions. Since projectors correspond to soliton solutions of the field theory on the noncommutative orbifold, we thus present a corresponding soliton solution. 展开更多
关键词 SOLITON projection operator noncommutative orbifold T2/Z4
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Some Properties of Causal Linear Time-Invariant(LTI) Operators on the Weighted l_(2) Space
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作者 Naifeng GAN Yufeng LU Liu LIU 《Journal of Mathematical Research with Applications》 CSCD 2015年第6期672-680,共9页
We discuss the properties of causal LTI operators on weighted ?2 spaces for different choices of the weighting sequence {w(t)}t∈Z. Problems of closability of unstable causal LTI convolution operators are also disc... We discuss the properties of causal LTI operators on weighted ?2 spaces for different choices of the weighting sequence {w(t)}t∈Z. Problems of closability of unstable causal LTI convolution operators are also discussed. We shall provide a new type of argument concerning causal LTI operators and robust design that can be applied to a large class of weighted ?2 spaces on Z. 展开更多
关键词 causal LTI operators weighted l_(2) space two-operator approach
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The two-mode quantum Fresnel operator and the multiplication rule of 2D Collins diffraction formula
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作者 谢传梅 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期296-300,共5页
By using the two-mode Fresnel operator we derive a multiplication rule of two-dimensional (2D) Collins diffraction formula, the inverse of 2D Collins diffraction integration can also be conveniently derived in this ... By using the two-mode Fresnel operator we derive a multiplication rule of two-dimensional (2D) Collins diffraction formula, the inverse of 2D Collins diffraction integration can also be conveniently derived in this way in the context of quantum optics theory. 展开更多
关键词 2D Collins diffraction formula two-mode Fresnel operator
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Residual Operator of Type-2 Triangular Norms on Convex Normal Upper Semi-Continuous Fuzzy Truth Values
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作者 Xinxing WU Shuangfeng LUO +1 位作者 Zhiyi ZHU Lidong WANG 《Journal of Mathematical Research with Applications》 CSCD 2024年第3期285-290,共6页
Based on the residual implication of continuous triangular norms,we obtain the expression of residual operator for extended operators(type-2 triangular norms)of continuous triangular norms on convex normal upper semi-... Based on the residual implication of continuous triangular norms,we obtain the expression of residual operator for extended operators(type-2 triangular norms)of continuous triangular norms on convex normal upper semi-continuous fuzzy truth values,answering an open problem in[D.LI,Inf.Sci.,2015,317:259-277]. 展开更多
关键词 type-2 fuzzy set triangular norm(t-norm) residual operator
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THE L^2-BOUNDEDNESS OF PSEUDODIFFERENTIAL OPERATORS WITH NONSMOOTH COEFFICIENT SYMBOLS
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作者 李得宁 《Acta Mathematica Scientia》 SCIE CSCD 1989年第1期1-5,共5页
1. Introduction In application of nonlinear boundary value problems, it is sometimes important to know that L~2-boundedness of a class of pseudo-differential operators with symbols whioh have nonsmooth coefficients. I... 1. Introduction In application of nonlinear boundary value problems, it is sometimes important to know that L~2-boundedness of a class of pseudo-differential operators with symbols whioh have nonsmooth coefficients. In [2], Coifman and Meyer proved that the operator σ(x, D) is bounded in L~2(R~n) if its symbold (x, ξ) satisfies: 展开更多
关键词 TH THE L~2-BOUNDEDNESS OF PSEUDODIFFERENTIAL operatorS WITH NONSMOOTH COEFFICIENT SYMBOLS
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Implicit Variational Inclusions and Algorithms Involving (A, η)-monotone Operators in 2-uniformly Smooth Banach Spaces
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作者 N. K. Sahu 《Journal of Mathematics and System Science》 2015年第6期269-278,共10页
This paper deals with a new class of nonlinear set valued implicit variational inclusion problems involving (A, η)-monotone mappings in 2-uniformly smooth Banach spaces. Semi-inner product structure has been used t... This paper deals with a new class of nonlinear set valued implicit variational inclusion problems involving (A, η)-monotone mappings in 2-uniformly smooth Banach spaces. Semi-inner product structure has been used to study the (A, η)-monotonicity. Using the generalized resolvent operator technique and the semi-inner product structure, the approximation solvability of the proposed problem is investigated. An iterative algorithm is constructed to approximate the solution of the problem. Convergence analysis of the proposed algorithm is investigated. Similar results are also investigated for variational inclusion problems involving (H, η)-monotone mappings. 展开更多
关键词 Semi-inner product space Generalized resolvent operator Variational inclusion 2-uniformly smooth Banach space.
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针对模糊需求的VRP的两种2-OPT算法 被引量:18
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作者 祝崇隽 刘民 +1 位作者 吴澄 吴晓冰 《电子学报》 EI CAS CSCD 北大核心 2001年第8期1035-1037,共3页
本文研究了一类客户需求不确定的VRP(车辆路径问题 ) .在算法中 ,引入了伪出发点和新的聚类判定规则 ,将聚类和排序有机的结合起来 ,有效地处理了全局采样和局部搜索之间的矛盾 .给出了基于可能性分布的 2 OPT算法和基于需求上界的 2 ... 本文研究了一类客户需求不确定的VRP(车辆路径问题 ) .在算法中 ,引入了伪出发点和新的聚类判定规则 ,将聚类和排序有机的结合起来 ,有效地处理了全局采样和局部搜索之间的矛盾 .给出了基于可能性分布的 2 OPT算法和基于需求上界的 2 OPT算法 ,并用模糊模拟技术进行了实验 .大量的实验结果表明 ,这两种方法明显优于这个领域现有的算法 。 展开更多
关键词 VRP问题 可能性分布 2-opt算法
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保存基因的2-Opt一般反向差分演化算法 被引量:6
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作者 刘罡 李元香 郑昊 《小型微型计算机系统》 CSCD 北大核心 2012年第4期789-794,共6页
为了进一步提高差分演化算法的性能,提出一种采用保存基因的2-Opt一般反向差分演化算法,并把它应用于函数优化问题中.新算法具有以下特征:(1)采用保存被选择个体基因的方式组成参加演化的新个体.保存基因的方法可以很好的保持种群多样性... 为了进一步提高差分演化算法的性能,提出一种采用保存基因的2-Opt一般反向差分演化算法,并把它应用于函数优化问题中.新算法具有以下特征:(1)采用保存被选择个体基因的方式组成参加演化的新个体.保存基因的方法可以很好的保持种群多样性;(2)采用一般反向学习(GOBL)机制进行初始化,提高了初始化效率;(3)采用2-Opt算法加速差分演化算法的收敛速度,提高搜索效率.通过测试函数的实验,并与其他差分演化算法进行比较.实验结果证实了新算法的高效性,通用性和稳健性. 展开更多
关键词 差分演化 一般反向学习 2-opt算法 保存基因 函数优化
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一种并行ACS-2-opt算法处理TSP问题的方法 被引量:9
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作者 李俊 童钊 王政 《计算机科学》 CSCD 北大核心 2018年第B11期138-142,共5页
针对基本ACS算法模型求解TSP问题的缺陷,对ACS算法添加2-opt邻域搜索策略,增强算法对TSP问题解的构造能力,提高算法对TSP问题的求解精度。同时,根据ACS算法易于并行化的特点,使用并行化ACS算法与算法参数优化混合方案,提高ACS算法求解TS... 针对基本ACS算法模型求解TSP问题的缺陷,对ACS算法添加2-opt邻域搜索策略,增强算法对TSP问题解的构造能力,提高算法对TSP问题的求解精度。同时,根据ACS算法易于并行化的特点,使用并行化ACS算法与算法参数优化混合方案,提高ACS算法求解TSP问题的速度。最终实现了对中等规模TSP问题具有较好求解性能的并行ACS-2-opt算法。实验结果表明,2-opt策略对于提升ACS算法的求解精度具有明显的效果;采用不同参数设定信息素启发因子时,求解时间具有较大差异;在采用节点距离倒数作为期望启发值时,ACS算法模型呈现退化性;在并行条件下,ACS-2-opt算法处理TSP问题时具有良好的并行性能。 展开更多
关键词 2-opt邻域搜索策略 ACS算法 TSP问题 并行计算
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基于PGA-2-OPT算法的焊接机器人路径规划
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作者 刘良斌 赵自鹏 王瑶茜 《电脑与电信》 2023年第8期42-45,共4页
针对白车身焊接过程中焊点数量大、焊接顺序规划凭借经验的问题,提出了将焊接顺序和路径的规划问题转换为TSP问题的方案。传统遗传算法对种群多样化要求较高,后期易陷入局部最优问题;基本单亲遗传算法存在路径交叉问题。文章先对焊接任... 针对白车身焊接过程中焊点数量大、焊接顺序规划凭借经验的问题,提出了将焊接顺序和路径的规划问题转换为TSP问题的方案。传统遗传算法对种群多样化要求较高,后期易陷入局部最优问题;基本单亲遗传算法存在路径交叉问题。文章先对焊接任务采用单亲遗传算法得到相对最优解,然后采用2-OPT领域搜索策略,消除路径存在的交叉问题。文章以宝马某车型右前门板焊接任务为例,对焊接轨迹进行优化。改进后的车门焊接轨迹在同等进化代数的情况下,比传统遗传算法缩短了46%,比原有的单亲遗传算法缩短了29%。实验表明,通过PGA-2-OPT算法可以实现车门板焊接路径的优化,并能很好地消除路径交叉问题。 展开更多
关键词 单亲遗传算法 白车身焊接 2-opt
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运行工况对超临界CO_(2)干气密封端面热力学过程及稳态性能影响研究 被引量:1
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作者 江锦波 陈竹鑫 +5 位作者 肖洋溢 彭新 陈源 于辰 孟祥铠 彭旭东 《化工学报》 北大核心 2025年第6期2913-2928,共16页
超临界CO_(2)压缩机干气密封因密封介质在临界点工况附近的物性特殊性和高参数化,密封间隙内介质流动呈现出多相流动、高度湍流化和物性畸变特征。以微段组合型槽干气密封为研究对象构建了轴向力平衡条件下考虑实际流体效应的超临界CO_... 超临界CO_(2)压缩机干气密封因密封介质在临界点工况附近的物性特殊性和高参数化,密封间隙内介质流动呈现出多相流动、高度湍流化和物性畸变特征。以微段组合型槽干气密封为研究对象构建了轴向力平衡条件下考虑实际流体效应的超临界CO_(2)干气密封热动力润滑相变仿真模型,提出了密封端面热力学过程表征方法,研究了转速、进气压力和进气温度等运行工况参数对超临界CO_(2)干气密封端面热力学过程、流场参数和稳态性能的影响。结果表明:进气温度的提高对于抑制密封端面液相凝析效果显著;转速和进气压力的增大只能抑制槽区液相凝析,增大端面非液相区面积,但对密封坝气液混相区影响不大,当进气温度达到320 K和340 K时,端面纯液相区和气液混相区先后消失;提高非液相区面积,对于增大密封气膜刚度是有利的。 展开更多
关键词 超临界CO_(2) 干气密封 相变 工况参数 热力学过程
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