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Element-free Galerkin method for free vibration of rectangular plates with interior elastic point supports and elastically restrained edges 被引量:1
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作者 王砚 王忠民 阮苗 《Journal of Shanghai University(English Edition)》 CAS 2010年第3期187-195,共9页
The element-free Galerkin method is proposed to solve free vibration of rectangular plates with finite interior elastic point supports and elastically restrained edges.Based on the extended Hamilton's principle for t... The element-free Galerkin method is proposed to solve free vibration of rectangular plates with finite interior elastic point supports and elastically restrained edges.Based on the extended Hamilton's principle for the elastic dynamics system,the dimensionless equations of motion of rectangular plates with finite interior elastic point supports and the edge elastically restrained are established using the element-free Galerkin method.Through numerical calculation,curves of the natural frequency of thin plates with three edges simply supported and one edge elastically restrained,and three edges clamped and the other edge elastically restrained versus the spring constant,locations of elastic point support and the elastic stiffness of edge elastically restrained are obtained.Effects of elastic point supports and edge elastically restrained on the free vibration characteristics of the thin plates are analyzed. 展开更多
关键词 element free method rectangular thin plates interior elastic point supports elastically restrained edges free vibration
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AN EXACT SOLUTION FOR THE BENDING OF POINT-SUPPORTED ORTHOTROPIC RECTANGULAR THIN PLATES 被引量:1
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作者 姜稚清 刘金喜 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第6期547-557,共11页
A closed series solution is proposed for the bending of point-supported orthotropic rectangular thin plates. The positions of support points and the distribution of transverse loadare arbitrary. If the number of simpl... A closed series solution is proposed for the bending of point-supported orthotropic rectangular thin plates. The positions of support points and the distribution of transverse loadare arbitrary. If the number of simply supported points gradually increases the solution can infinitely approach to Navier's solution. For the square plate simply supported on the middle of each edge and free at each corner, the results are very close to the numerical solutions in the past. 展开更多
关键词 exact solution point supports orthotropic rectangular thin plate
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THE SYMMETRICAL BENDING OF AN ELASTIC CIRCULAR PLATE SUPPORTED AT KINTERNAL POINTS
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作者 李农 付宝连 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第11期1091-1096,共6页
This paper treats the symmetrical bending of a uniformly loaded circular plate supported at k internal points. The boundary displacement and slope are expanded in Fourier seriesr. The method proposed by [6] is applied... This paper treats the symmetrical bending of a uniformly loaded circular plate supported at k internal points. The boundary displacement and slope are expanded in Fourier seriesr. The method proposed by [6] is applied. As both the governing differential equation and boundary conditions are satisfied exactly, we therefore obtain the analytic expression of the transverse deflectionul equation of the circular plate. This is an easy and effective methed. 展开更多
关键词 internal point support symmetrical bending deflectional equation
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EXTREME POINTS AND SUPPORT POINTS OF A CLASS OF ANALYTIC FUNCTIONS 被引量:2
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作者 彭志刚 刘伦刚 《Acta Mathematica Scientia》 SCIE CSCD 2000年第1期131-136,共6页
Suppose that {b(n)} and {c(n)} are two positive sequences. Let F({b(n)}, {c(n)}) = {f(z) : f(z) is analytic in \z\ < 1, f(z) = z - Sigma(n=2)(+infinity) a(n)z(n), a(n) greater than or equal to 0, Sigma(n=2)(+infini... Suppose that {b(n)} and {c(n)} are two positive sequences. Let F({b(n)}, {c(n)}) = {f(z) : f(z) is analytic in \z\ < 1, f(z) = z - Sigma(n=2)(+infinity) a(n)z(n), a(n) greater than or equal to 0, Sigma(n=2)(+infinity) b(n)a(n) less than or equal to 1 and Sigma(n=2)(+infinity) c(n)a(n) less than or equal to 1}. This article obtains the extreme points and support points of F({b(n)}, {c(n)}). 展开更多
关键词 topology of uniform convergence compact subsets of the unit disk extreme point support point
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Three-dimensional elasticity solution of simple-supported rectangular plate on point supports, line supports and elastic foundation 被引量:1
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作者 XU YePeng1 & ZHOU Ding2 1 School of Science, Nanjing University of Science and Technology, Nanjing 210094, China 2 College of Civil Engineering, Nanjing University of Technology, Nanjing 210009, China 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第3期584-589,共6页
This paper studies the bending of simple-supported rectangular plate on point supports, line supports and elastic foundation. On the basis of three-dimensional elasticity theory, the exact expressions of the displacem... This paper studies the bending of simple-supported rectangular plate on point supports, line supports and elastic foundation. On the basis of three-dimensional elasticity theory, the exact expressions of the displacement functions, which satisfy the governing differential equations and the simply supported boundary conditions at four edges of the plate, are analytically derived. The reaction forces of the in- termediate supports are regarded as the unknown external forces acting on the lower surface of the plate. The unknown coefficients are then determined by the boundary conditions on the upper and lower surfaces of the plate. Comparing the numerical results obtained from the proposed method to those obtained from Kirchhoff plate theory, Mindlin plate theory and those obtained from the commer- cial finite element software ANSYS, the high accuracy of the present method has been demonstrated. 展开更多
关键词 rectangular plate point support LINE support elastic FOUNDATION DISPLACEMENT stress THREE-DIMENSIONAL ELASTICITY solution
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THE SUPPORT POINTS AND EXTREME POINTS OF THE UNIT BALL OF H'_P~ 1
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作者 彭志刚 《Acta Mathematica Scientia》 SCIE CSCD 1999年第2期181-189,共9页
By the author denotes the areal measure on the unit disk . Let H'p = {f(z): f(z) is analytic in D and . Let B H 'p and. This article researches the support points and extreme points of B(H'p).
关键词 Topology of uniform convergence compact subsets of unit disk Extreme point support point.
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TRANSVERSE VIBRATION OF RECTANGULAR PLATES ELASTICALLY SUPPORTED AT POINTS ON EDGES
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作者 周叮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第10期979-987,共9页
This paper studies transverse vibration of rectangular plates with two opposite edges simply supperted other two edges arbitrarily supported and free edges elaslically supported at points,A highly accurate solution is... This paper studies transverse vibration of rectangular plates with two opposite edges simply supperted other two edges arbitrarily supported and free edges elaslically supported at points,A highly accurate solution is presented for calculating inherent frequencies and mode shape of rectangular platen elaslically supported at points. The number and location of these points on free edges may be completely arbitrary. This paper uses impulse function to represent reaction and moment at points. Fourter series is used to expand the impulse function along the edges. Characteristic equations satisfying all boundary conditions are given.Inherent frequencies and mode shape with any accutacy can be gained. 展开更多
关键词 TRANSVERSE VIBRATION OF RECTANGULAR PLATES ELASTICALLY supportED AT pointS ON EDGES MODE AT
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VIBRATIONS OF RECTANGULAR PLATES SUPPORTED AT CORNER POINTS
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作者 成祥生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第8期751-757,共7页
This paper discusses by energy theorem the methodof approximate computation for the lowest eigenfrequencies of rechmguhir plates,on which there are symmetrical concentrated masses,supported at corner points,In the cas... This paper discusses by energy theorem the methodof approximate computation for the lowest eigenfrequencies of rechmguhir plates,on which there are symmetrical concentrated masses,supported at corner points,In the case of seseral concentrated masses,by using the prineiple of superposition we mayfiml the reduneed coefficients of masses comveniently.llence we can louain the lowest eigenfrequencies of thin plates.In the paper a good mamy mmerical caleuhting eximples are inustrated 展开更多
关键词 MODE VIBRATIONS OF RECTANGULAR PLATES supportED AT CORNER pointS
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VIBRATION OF ARBITRARILY SHAPED MEMBRANES WITH ELASTICAL SUPPORTS AT POINTS
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作者 周叮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第12期1171-1177,共7页
This paper presents a new method for solving the vibration of arbitrarily shaped membranes with ela.stical supports at points. The reaction forces of elastical supports at points are regarded as unknown external force... This paper presents a new method for solving the vibration of arbitrarily shaped membranes with ela.stical supports at points. The reaction forces of elastical supports at points are regarded as unknown external forces acting on the membranes. The exact solution of the equation of motion is given which includes terms representing the unknown reaction forces. The frequency equation is derived by the use of the linear relationship of the displacements with the reaction forces of elastical supports at points. Finally the calculating formulae of the frequency equation of circular membranes are analytically performed as examples and the inherent frequencies of circular membranes with symmetric elastical supports at two points are numerically calculated. 展开更多
关键词 VIBRATION OF ARBITRARILY SHAPED MEMBRANES WITH ELASTICAL supportS AT pointS
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复杂地基条件下真空负压桩锚支护深基坑土方开挖稳定性数值模拟
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作者 胡碧波 田战飞 +2 位作者 李绍辰 商恩铭 王瑶 《真空》 2026年第1期103-108,共6页
复杂地基包含软弱层、岩溶区域及多变地质结构等复杂状况,该类型地基存在地质结构非均质性、地层变化不确定性以及地下水位过高等问题。桩锚支护作为深基坑开挖的关键技术,其稳定性对工程安全起决定性作用。为确保深基坑土方开挖安全,... 复杂地基包含软弱层、岩溶区域及多变地质结构等复杂状况,该类型地基存在地质结构非均质性、地层变化不确定性以及地下水位过高等问题。桩锚支护作为深基坑开挖的关键技术,其稳定性对工程安全起决定性作用。为确保深基坑土方开挖安全,对复杂地基条件下桩锚支护深基坑土方开挖稳定性进行数值模拟具有重要意义。以某城市商业综合体项目中的深基坑开挖工程为研究案例,在分析深基坑所在地质条件和土层特性的基础上,确定了三道桩锚支护方案以及相应应用参数,结合真空井点降水法,采用真空泵在井点管内形成负压以降低地下水位。通过改进摩尔库仑本构模型的土层参数,明确桩锚支护各结构的单元模拟属性。以十组工况作为边界条件,完成复杂地基条件下的相关数值模拟。结果表明,开挖过程中桩顶水平位移变化速率较快,随工况推进,桩顶水平位移逐渐增加,但稳定后的水平位移处于预警值内;桩锚支护土方开挖方式对周围地层的影响较小,最大沉降位移值也处于预警值之内,具有一定的稳定开挖效果。 展开更多
关键词 复杂地基 桩锚支护施工 真空井点降水法 土方开挖 数值模拟
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SUPPORTING AND SEPARATING SUBSETS FOR INVEX BODIES
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作者 H.K.El-Sayied 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期818-822,共5页
Invex bodies represent an important class of bodies which are considered as a generalization of convex bodies.In this article,the author studies the supporting for this class of bodies as well as the separating subset... Invex bodies represent an important class of bodies which are considered as a generalization of convex bodies.In this article,the author studies the supporting for this class of bodies as well as the separating subsets of two bodies. 展开更多
关键词 Invex bodies focal points-supporting SEPARATING
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THE UNIT BALL OF C-ALGEBRA AND DIFFERENTIABILITY OF SUPPORT FUNCTION
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作者 Y.Dehghan I.Sadeqi 《Analysis in Theory and Applications》 2005年第1期53-57,共5页
In this paper we show that the unit ball of an infinite dimensional commutative C-algebra lacks strongly exposed points, so they have no predual. Also in the second part, we use the concept of strongly exposed points ... In this paper we show that the unit ball of an infinite dimensional commutative C-algebra lacks strongly exposed points, so they have no predual. Also in the second part, we use the concept of strongly exposed points in the Frechet differentiability of support convex functions. 展开更多
关键词 Radon-Nikodym property dentability support functional exposed point
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RH精炼炉脱碳氧位的预测控制研究
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作者 王姿涵 张宇鹏 +4 位作者 赵定国 薛月凯 王书桓 李晨晓 周朝刚 《冶金能源》 北大核心 2026年第1期70-75,共6页
为了准确预测RH精炼炉的脱碳氧位,基于某厂生产数据,应用随机森林算法,BP神经网络模型和支持向量回归模型分别划分训练集和测试集,预测了脱碳氧位。结果表明:BP神经网络模型的预测效果比另外两种模型性能更好,在5%以内的范围预测准确率... 为了准确预测RH精炼炉的脱碳氧位,基于某厂生产数据,应用随机森林算法,BP神经网络模型和支持向量回归模型分别划分训练集和测试集,预测了脱碳氧位。结果表明:BP神经网络模型的预测效果比另外两种模型性能更好,在5%以内的范围预测准确率达到85%。随后统计了在不同条件下的氧位分布情况,并通过影响因素的权值对新的样本的冶炼周期、最高真空度、吹氧量、氮气消耗进行调整,基于BP神经网络模型进行了实验验证,最终实现了RH精炼炉脱碳氧位的窄范围控制。 展开更多
关键词 RH精炼 BP神经网络模型 支持向量回归模型 随机森林算法 脱碳氧位
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考虑抗剪性能的全长预应力锚杆支护力计算方法
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作者 陈志敏 王洪 +2 位作者 李亚子 龚军 李增印 《应用力学学报》 北大核心 2025年第5期1098-1105,共8页
为探明全长预应力锚杆对剪切滑移体的抗剪性能,基于剪切滑移理论提出了一种计算滑移体所需最小支护抗力的方法,推导了全长预应力锚杆的中性点位置和支护力计算方法,并应用于隧道案例中验证其合理性。研究表明:用滑移体面积和围岩等级计... 为探明全长预应力锚杆对剪切滑移体的抗剪性能,基于剪切滑移理论提出了一种计算滑移体所需最小支护抗力的方法,推导了全长预应力锚杆的中性点位置和支护力计算方法,并应用于隧道案例中验证其合理性。研究表明:用滑移体面积和围岩等级计算滑移体所需最小抗力的方法相比于传统的方法计算简便、安全度高。在规定范围内:增大锚杆直径,中性点位置向锚杆尾部移动;增大预应力,中性点位置向锚杆端部移动,两者对锚杆中性点位置的影响不同,但均能使锚杆轴力和径向支护抗力成正比例关系增大。采用锚喷支护时锚杆所能提供的径向支护抗力很小,建议根据滑移面处剪力值设计锚杆参数,适当增大直径和预应力,提高抗剪性能的同时也能提高径向支护抗力。研究成果可为全长预应力锚杆的抗剪性能计算提供参考。 展开更多
关键词 软岩隧道 剪切滑移理论 锚喷支护 中性点 支护抗力
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王东红教授耳穴扶阳疗法在多囊卵巢综合征中的应用
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作者 张茜薇 王东红 《中国中医药现代远程教育》 2025年第13期90-92,共3页
多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是常见的妇科内分泌疾病。王东红教授临证辨治PCOS多年,将该病的病机总结为“肾虚、痰瘀互结”,主张采用中药人工周期疗法分期治疗,以恢复患者月经周期,促进排卵。治疗全过程尤注重扶助... 多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是常见的妇科内分泌疾病。王东红教授临证辨治PCOS多年,将该病的病机总结为“肾虚、痰瘀互结”,主张采用中药人工周期疗法分期治疗,以恢复患者月经周期,促进排卵。治疗全过程尤注重扶助阳气,温补肾阳的药物贯穿始终。王东红教授还总结了一套耳穴扶阳疗法,在扶助和温通阳气方面效果显著,形成了自身诊疗特色,提高了临床效果。 展开更多
关键词 多囊卵巢综合征 耳穴疗法 扶阳法 王东红 名医经验
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Blind source separation algorithm based on support vector machines 被引量:1
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作者 HE Xuan-sen HU Bo-ping 《通讯和计算机(中英文版)》 2008年第11期7-12,共6页
关键词 通信技术 盲源分离算法 计算方法 径向基函数 概率密度函数
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基于支持向量机的三维点云岩体结构面半自动识别方法 被引量:5
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作者 朱涛 史文兵 +2 位作者 刘永志 王勇 梁风 《防灾减灾工程学报》 北大核心 2025年第1期95-103,共9页
结构面在评价岩体力学性质和边坡稳定性方面起着至关重要的作用,相比于传统测量,一种准确、高效的结构面参数识别方法尤为重要。提出了一种基于支持向量机(SVM)的三维点云岩体结构面提取的新方法,首先获取点云坐标、RGB、法向量、曲率... 结构面在评价岩体力学性质和边坡稳定性方面起着至关重要的作用,相比于传统测量,一种准确、高效的结构面参数识别方法尤为重要。提出了一种基于支持向量机(SVM)的三维点云岩体结构面提取的新方法,首先获取点云坐标、RGB、法向量、曲率和密度等作为机器学习模型的特征向量作为输入,结合人工和自动挑选学习样本,随后把学习样本分为训练集和测试集用于训练SVM模型并测试模型,将被接受的模型用于点云的预测分类,进而识别结构面和提取信息。将该方法应用于公开边坡数据集和发耳镇某采区边坡结构面调查,结果表明:使用LOF与PCA结合方法有效地提高了法向量估计的准确性,而DetRD-PCA方法用于估计单个结构面的法向量并计算产状时得到结果更加准确;对公开点云数据集的结构面进行识别,SVM识别881552个点时间仅需9 s,成功提取了四组结构面,与前人结果对比,倾向平均偏差最大3.12°,倾角平均偏差最大1.54°;将方法应用于发耳镇某采区边坡的结构面调查中,SVM识别1450148个点仅需18 s,成功提取了两组结构面,与经典的三点法估算比较,倾向和倾角的偏差为0.7°~3.3°和0.1°~3.3°;该方法对于小样本的训练数据依然能够表现出较高的正确率。 展开更多
关键词 三维点云 支持向量机 岩体结构面 半自动识别 产状计算 工程应用
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多支点择业倾向视域下高职院校职业规划指导研究
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作者 褚蓉 《宿州职业技术学院学报》 2025年第5期51-57,共7页
高职院校毕业生是青年就业人群的主要组成部分。确定符合个人特质的择业支点对大学生长期职业发展有着重要作用。新质生产力引导下融合性职业指导服务体系构建、以人为本前提下分类指导体系构建、全周期指导下多支点相融合的职业支点优... 高职院校毕业生是青年就业人群的主要组成部分。确定符合个人特质的择业支点对大学生长期职业发展有着重要作用。新质生产力引导下融合性职业指导服务体系构建、以人为本前提下分类指导体系构建、全周期指导下多支点相融合的职业支点优化,这些是多支点职业指导视域下高职院校毕业生择业倾向培养的关键部分。 展开更多
关键词 择业支点 职业规划指导 新质生产力
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点支单层玻璃面板反双曲冷弯成形稳定性研究 被引量:1
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作者 郝小涵 陈素文 陈志飞 《工程力学》 北大核心 2025年第9期86-95,共10页
反双曲玻璃面板是自由曲面玻璃幕墙的重要组成部分,可通过反双曲冷弯的方式实现,在面板冷弯成形过程中,稳定问题常先于强度问题发生。该文分析了点支单层玻璃面板的冷弯成形过程,明确了冷弯成形过程的失稳模式为分支点失稳和冷弯畸变;... 反双曲玻璃面板是自由曲面玻璃幕墙的重要组成部分,可通过反双曲冷弯的方式实现,在面板冷弯成形过程中,稳定问题常先于强度问题发生。该文分析了点支单层玻璃面板的冷弯成形过程,明确了冷弯成形过程的失稳模式为分支点失稳和冷弯畸变;建立了可有效模拟冷弯成形的有限元模型,系统分析了点支承条件、重力下的初始形状和加载方向、初始缺陷、玻璃钢化、几何尺寸对单层玻璃面板反双曲冷弯稳定性的影响,进一步探讨了冷弯成形过程中的稳定问题;拟合得到不同尺寸玻璃面板的冷弯失稳荷载及角点位移公式。该文为冷弯实现反双曲玻璃面板奠定了基础。 展开更多
关键词 稳定性 反双曲冷弯 有限元 点支 单层玻璃面板
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车载液氢瓶六点支撑与八点支撑方案热力耦合特性对比研究
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作者 朱宇豪 谢福寿 +1 位作者 王双进 厉彦忠 《真空与低温》 2025年第1期62-73,共12页
氢能作为一种绿色清洁能源,在新能源汽车领域受到了广泛关注。尤其是低温液氢存储,因具有储氢密度高等优势而成为了一种理想的车载储氢方式。车载液氢瓶是液氢燃料车的关键部件之一,其支撑结构将直接影响到整个液氢瓶的绝热性能和力学... 氢能作为一种绿色清洁能源,在新能源汽车领域受到了广泛关注。尤其是低温液氢存储,因具有储氢密度高等优势而成为了一种理想的车载储氢方式。车载液氢瓶是液氢燃料车的关键部件之一,其支撑结构将直接影响到整个液氢瓶的绝热性能和力学性能。采用有限元分析方法,从强度校核、模态分析和随机振动疲劳分析三个方面,对基于六点支撑方案和八点支撑方案的液氢瓶结构进行了对比分析,研究结果表明,玻璃钢柱皆采用10 mm径向厚度时,八点支撑方案能够达到强度校核标准,但六点支撑方案却不能满足强度要求;为了满足强度校核条件,六点支撑方案中需增加玻璃钢柱的径向厚度,但这也导致了更大的支撑漏热;设计参数下,六点支撑方案和八点支撑方案中的支撑漏热分别为23.65 W和22.49 W,疲劳寿命分别为1.01×10^(7)次和9.19×10^(7)次;相较于八点支撑方案,六点支撑方案中液氢瓶虽然减少了支撑端的数量,但绝热性能并没有得到有效提升,且使用寿命反而大幅降低。 展开更多
关键词 六点支撑 八点支撑 车载液氢瓶 强度校核 疲劳寿命
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