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Sandwich structures with tapered tubes as core:A quasi-static investigation
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作者 Xinmei Xiang Dehua Shao +5 位作者 Xin Zhang Umer Sharif Ngoc San Ha Li Xiang Jing Zhang Jiang Yi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期447-462,共16页
In this article,the experimental and finite element analysis is utilized to investigate the quasi-static compression features of sandwich constructions built with tapered tubes.3D printing technology was utilized to c... In this article,the experimental and finite element analysis is utilized to investigate the quasi-static compression features of sandwich constructions built with tapered tubes.3D printing technology was utilized to create the hollow centers of the tapering tubes,with and without corrugations.The results demonstrate that the energy absorption(EA)and specific energy absorption(SEA)of the single corrugated tapered tube sandwich are 51.6% and 19.8% higher,respectively,than those of the conical tube sandwich.Furthermore,the results demonstrate that energy absorbers can benefit from corrugation in order to increase their efficiency.Additionally,the tapered corrugated tubes'resistance to oblique impacts was studied.Compared to a straight tube,the tapered tube is more resistant to oblique loads and has a lower initial peak crushing force(PCF),according to numerical simulations.After conducting a parametric study,it was discovered that the energy absorption performance of the sandwich construction is significantly affected by the amplitude,number of corrugations,and wall thickness.EA and SEA of DTS with corrugation number of 8 increased by 17.4%and 29.6%,respectively,while PCF decreased by 9.2% compared to DTS with corrugation number of 10. 展开更多
关键词 Sandwich structure Corrugated tube Tapered tube QUASI-STATIC Energy absorption
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A novel slotted helix slow-wave structure for high power Ka-band traveling-wave tubes 被引量:1
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作者 刘鲁伟 魏彦玉 +8 位作者 王少萌 侯艳 殷海荣 赵国庆 段兆云 徐进 宫玉彬 王文祥 杨明华 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期593-597,共5页
A novel slotted helix slow-wave structure (SWS) is proposed to develop a high power, wide-bandwidth, and high reliability millimeter-wave traveling-wave tube (TWT). This novel structure, which has higher heat capa... A novel slotted helix slow-wave structure (SWS) is proposed to develop a high power, wide-bandwidth, and high reliability millimeter-wave traveling-wave tube (TWT). This novel structure, which has higher heat capacity than a conven- tional helix SWS, evolves from conventional helix SWS with three parallel rows of rectangular slots made in the outside of the helix tape. In this paper, the electromagnetic characteristics and the beam-wave interaction of this novel structure operating in the Ka-band are investigated. From our calculations, when the designed beam voltage and beam current are set to be 18.45 kV and 0.2 A, respectively, this novel circuit can produce over 700-W average output power in a frequency range from 27.5 GHz to 32.5 GHz, and the corresponding conversion efficiency values vary from 19% to 21.3%, and the maximum output power is 787 W at 30 GHz. 展开更多
关键词 slotted helix slow-wave structure MILLIMETER-WAVE traveling-wave tube beam-wave interaction
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Performance-based global reliability assessment of a high-rise frame-core tube structure subjected to multi-dimensional stochastic earthquakes 被引量:2
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作者 Liu Zhangjun Ruan Xinxin Liu Zixin 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第2期395-415,共21页
When evaluating the seismic safety and reliability of complex engineering structures,it is a critical problem to reasonably consider the randomness and multi-dimensional nature of ground motions.To this end,a proposed... When evaluating the seismic safety and reliability of complex engineering structures,it is a critical problem to reasonably consider the randomness and multi-dimensional nature of ground motions.To this end,a proposed modeling strategy of multi-dimensional stochastic earthquakes is addressed in this study.This improved seismic model has several merits that enable it to better provide seismic analyses of structures.Specifically,at first,the ground motion model is compatible with the design response spectrum.Secondly,the evolutionary power spectrum involved in the model and the design response spectrum are constructed accordingly with sufficient consideration of the correlation between different seismic components.Thirdly,the random function-based dimension-reduction representation is applied,by which seismic modeling is established,with three elementary random variables.Numerical simulations of multi-dimensional stochastic ground motions in a specific design scenario indicate the effectiveness of the proposed modeling strategy.Moreover,the multi-dimensional seismic response and the global reliability of a high-rise frame-core tube structure is discussed in detail to further illustrate the engineering applicability of the proposed method.The analytical investigations demonstrate that the suggested stochastic model of multi-dimensional ground motion is available for accurate seismic response analysis and dynamic reliability assessment of complex engineering structures for performance-based seismic resistance design. 展开更多
关键词 multi-dimensional stochastic ground motion dimension-reduction representation frame-core tube structure global dynamic reliability performance-based seismic design
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Nonlinear seismic response analysis of reinforced concrete tube in tube structure 被引量:1
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作者 WANG Hai-bo SHEN Pu-sheng 《Journal of Central South University of Technology》 2005年第z1期183-188,共6页
Super-highly reinforced concrete tube in tube structure is a developing structure system of high-rise building. The more reasonable derivation process of the multi-vertical-line-element model stiffness matrix is given... Super-highly reinforced concrete tube in tube structure is a developing structure system of high-rise building. The more reasonable derivation process of the multi-vertical-line-element model stiffness matrix is given.On the premise of pointing out the problems of present multi-spring element model, combined with present multivertical-line-element model for analyzing on shear wall, the model is expanded to spatial one, and the stiffness matrix of which is derived. Combined with hysteretic axial model and hysteretic shear model, it is suitable for columns,wall limbs and beams with all kinds of section form. Some examples are calculated and compared with test results,which shows that the models have relatively good accuracy. On the base of the experimental phenomenon and failure mechanism for tube in tube structure specimen, nonlinear seismic responses analysis program on the basis of the advantaged element model for tube in tube structure is developed. Calculation results are in good agreement with those of the pseudo-dynamic tests and the failure mechanism can be well reflected. 展开更多
关键词 tube in tube structure of reinforced concrete SEISMIC responses nonlinear analysis multi-vertical-lineelement model multi-spring element PSEUDO-DYNAMIC test
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THEORETICAL STUDY ON THE BIFURCATION OF VORTEXES STRUCTURE FOR FLOW IN CURVED TUBE
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作者 吴望一 谭文长 +1 位作者 李娟 谢文俊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第12期1345-1358,共14页
The number and distribution of the singular points of streamlines in the cross-section of steady flow through a curved tube ate discussed by using the method of topological structure analysis. And a theoretical criter... The number and distribution of the singular points of streamlines in the cross-section of steady flow through a curved tube ate discussed by using the method of topological structure analysis. And a theoretical criterion is obtained for the bifurcation of flow vortexes for the secondary flow turning from two-vortex structure into four-vortex structure. Furthermore, the critical Dean number for bifurcation and the semi-analytical expressions of stream function and axial velocity are given by using Galerkin technique. The result of calculation is consistent with the theoretical criterion. 展开更多
关键词 curved tube steady flow BIFURCATION topological structure Galerkin technique
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Seismic behavior of concrete filled steel tubular arch structures 被引量:4
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作者 熊峰 Sashi K Kunnath 刘浩吾 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第1期107-115,共9页
Shaking table tests of a 1:10 scale arch model performed to investigate the seismic behavior and resistance of concrete filled steel tubular (CFT) arch structures are described in this paper. The El-Centro record and ... Shaking table tests of a 1:10 scale arch model performed to investigate the seismic behavior and resistance of concrete filled steel tubular (CFT) arch structures are described in this paper. The El-Centro record and Shanghai artificial wave were adopted as the input excitation. The entire test process can be divided into three stages depending on the lateral brace configurations, i.e., fully (five) braced, two braces removed, and all braces removed. A total of 46 tests, starting from the elastic state to failure condition, have been conducted. The natural vibration frequencies, responses of acceleration, displacement and strain were measured. From the test results, it is demonstrated that the CFT arch structures are capable of resisting severe ground motions and that CFT arches offer a credible alternative to reinforced concrete arches, especially in regions of high seismic intensity. 展开更多
关键词 concrete filled steel tube arch structures shaking table test seismic behavior lateral braces
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Crashworthiness Design and Multi-Objective Optimization for Bio-Inspired Hierarchical Thin-Walled Structures 被引量:5
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作者 Shaoqiang Xu Weiwei Li +2 位作者 Lin Li Tao Li Chicheng Ma 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第5期929-947,共19页
Thin-walled structures have been used in many fields due to their superior mechanical properties.In this paper,two types of hierarchical multi-cell tubes,inspired by the self-similarity of Pinus sylvestris,are propose... Thin-walled structures have been used in many fields due to their superior mechanical properties.In this paper,two types of hierarchical multi-cell tubes,inspired by the self-similarity of Pinus sylvestris,are proposed to enhance structural energy absorption performance.The finite element models of the hierarchical structures are established to validate the crashworthiness performance under axial dynamic load.The theoreticalmodel of themean crushing force is also derived based on the simplified super folded element theory.The finite element results demonstrate that the energy absorption characteristics and deformation mode of the bionic hierarchical thin-walled tubes are further improved with the increase of hierarchical sub-structures.It can be also obtained that the energy absorption performance of corner self-similar tubes is better than edge self-similar tubes.Furthermore,multiobjective optimization of the hierarchical tubes is constructed by employing the response surface method and genetic algorithm,and the corresponding Pareto front diagram is obtained.This research provides a new idea for the crashworthiness design of thin-walled structures. 展开更多
关键词 Bionic structure crashworthiness design hierarchical tube multi-objective optimization
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Thermal Structure of Glass Fiber Reinforce Plastic Support Structure 被引量:2
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作者 刘康 汪荣顺 +1 位作者 石玉美 顾安忠 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第3期370-374,共5页
The assembled form of thick-wall glass fiber reinforced plastics (GFRP) tube and 0Cr18Ni9 austenitic stainless steel pipes was designed as the radius thermal-insulating and load-supporting structure in cryogenic vesse... The assembled form of thick-wall glass fiber reinforced plastics (GFRP) tube and 0Cr18Ni9 austenitic stainless steel pipes was designed as the radius thermal-insulating and load-supporting structure in cryogenic vessels. In order to study the thermal leakage and gap changes on the support structure, as well as radius temperature and stress distribution on GFRP tube, an experimental investigation has been taken. The results indicate that the support structure is proved to fit well as thermal-insulating and load-supporting part in cryo-genic vessels, furthermore has high security during cryogenic applications. 展开更多
关键词 glass fiber reinforced plastics (GFRP) tube support structure CRYOGENIC temperature stress
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STRESS ANALYSIS OF RING STIFFENED TUBULAR JOINTS FOR OFFSHORE STRUCTURES——REVIEW OF STUDIES IN CHINA
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作者 Chen, Bozhen 《China Ocean Engineering》 SCIE EI 1990年第1期1-12,共12页
In China, the stress analysis of tubular joints for offshore structures was started at the end of 1970's. In addition to simple joints, the ring stiffened tubular joint have been analyzed recently. In this paper, ... In China, the stress analysis of tubular joints for offshore structures was started at the end of 1970's. In addition to simple joints, the ring stiffened tubular joint have been analyzed recently. In this paper, the author reviews the research work of stress analysis of ring stiffened joints, including brief introduction to the methods used, stress concentration behaviour, effects of ring stiffeners' number, location, dimension, type and stress distribution of ring stiffeners. Emperical formulae for predicting SCF of ring stiffened joints are also presented. 展开更多
关键词 Offshore structures Stresses ANALYSIS tubeS Stresses
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Application of color structured light pattern to measurement of large out-of-plane deformation
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作者 Xing Lu Jun-Hong Zhou Dong-Dong Liu Jue Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第6期1098-1104,共7页
Measurement of out-of-plane deformation is significant to understanding of the deflection mechanisms of the plate and tube structures.In this study,a new surface contouring technique with color structured light is app... Measurement of out-of-plane deformation is significant to understanding of the deflection mechanisms of the plate and tube structures.In this study,a new surface contouring technique with color structured light is applied to measure the out-of-plane deformation of structures with one-shot projection.Through color fringe recognizing,decoding and triangulation processing for the captured images corresponding to each deformation state,the feasibility of the method is testified by the measurement of elastic deflections of a flexible square plate,showing good agreement with those from the calibrated displacement driver.The plastic deformation of two alloy aluminum rectangular tubes is measured to show the technique application to surface topographic evaluation of the buckling structures with large displacements. 展开更多
关键词 Out-of-plane deformation Surface contouring Color structured light Plate deflection - Rectangular tube buckling
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Effects of Heat Exchange Tube Structural Parameters on Performance of Vehicle Radiator
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作者 Zeyan Liu Xilei Kong +3 位作者 Xiaobiao Han Hui Liu Quanzhen Wang Zhenling Wang 《Journal of Power and Energy Engineering》 2020年第9期1-7,共7页
In order to improve the performance of vehicle radiators, a two-dimensional heat transfer steady-state model of the radiator was set up. The influence of the structural parameters (axial ratio) of the heat exchange tu... In order to improve the performance of vehicle radiators, a two-dimensional heat transfer steady-state model of the radiator was set up. The influence of the structural parameters (axial ratio) of the heat exchange tube on the windward side on the heat transfer performance of the radiator was studied. With the increase of the axial ratio of the heat exchange tube on the windward side, the heat exchange capacity of the heat exchange tube surface slightly decreases. The heat exchange area increases significantly, which increases the total heat exchange of the radiator and improves the heat transfer performance of the radiator. When the axial ratio increases from 1.0 to 2.0, the average surface heat transfer capacity decreases from 5664.16</span><span style="font-family:""> </span><span style="font-family:Verdana;">W/m<sup>2</sup> to 5623.57</span><span style="font-family:""> </span><span style="font-family:Verdana;">W/m<sup>2</sup>. 展开更多
关键词 Vehicle Radiator Heat Transfer Performance Heat Exchange tube structure Parameters Axial Ratio
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Research on the Characteristic of the Disk-Loaded Waveguide, Rib-Loaded Disk-Loaded Waveguide and Helix Slow-Wave Structures
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作者 ZHANGYong 《Journal of Electronic Science and Technology of China》 2005年第2期188-189,共2页
关键词 traveling wave tube disk-loaded waveguide HELIX slow-wave structure dispersion characteristics interaction impedance plasma filled computer simulation rib-loaded hybrid mode
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框架承担倾覆力矩的合理计算方法 被引量:1
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作者 常磊 崔济东 +2 位作者 廖耘 周定 李盛勇 《建筑结构》 北大核心 2024年第4期124-135,共12页
为理清框架倾覆力矩的相关概念区别,并给出各自合理计算方法,对计算框架、支撑、框架+支撑、局部框架或者局部框架+支撑倾覆力矩的统一解法进行总结,给出相应的力学法。指出框架倾覆力矩和框架承担倾覆力矩之间的显著区别,给出两者的异... 为理清框架倾覆力矩的相关概念区别,并给出各自合理计算方法,对计算框架、支撑、框架+支撑、局部框架或者局部框架+支撑倾覆力矩的统一解法进行总结,给出相应的力学法。指出框架倾覆力矩和框架承担倾覆力矩之间的显著区别,给出两者的异同以及建筑结构中框架承担倾覆力矩的计算原则,并进一步给出合理计算框架承担倾覆力矩的方法,即修正的统一解法。修正的统一解法适用于一般建筑结构和带竖向构件转换的结构,也适用于带伸臂框架-核心筒结构。最后对典型结构算例的框架承担倾覆力矩进行计算分析,结果合理可行。 展开更多
关键词 倾覆力矩 框架结构 框架-剪力墙结构 剪力墙结构 带伸臂框架-核心筒结构 框支剪力墙结构 统一解法
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过盈配合工况下收缩管吸能特性分析及结构参数优化 被引量:1
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作者 许平 杨雨晖 +3 位作者 阳程星 邢杰 姚曙光 邹帆 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第4期1677-1689,共13页
轨道车辆收缩管在轴向冲击载荷及过盈配合下的吸能特性是吸能结构研究中的重要课题,其吸能过程依靠收缩管与锥形衬套之间的摩擦做工及收缩管的塑性变形实现,过盈配合通过影响收缩管与衬套间的接触力提高收缩管的能量耗散。为提高收缩管... 轨道车辆收缩管在轴向冲击载荷及过盈配合下的吸能特性是吸能结构研究中的重要课题,其吸能过程依靠收缩管与锥形衬套之间的摩擦做工及收缩管的塑性变形实现,过盈配合通过影响收缩管与衬套间的接触力提高收缩管的能量耗散。为提高收缩管的吸能特性,研究过盈配合对吸能能力的影响,采用试验与有限元模型相结合的方法,基于多目标优化算法获取包括过盈量在内的收缩管最优结构参数。进行空心轴与轴套过盈静压试验,验证接触力理论公式的正确性;利用台车冲击试验研究收缩管碰撞过程中的吸能特性,构建有限元模型进行验证;推导过盈配合条件下收缩管接触表面压力的理论模型;使用全因子和Hammersley设计方法对过盈配合工况下收缩管结构参数进行研究,包括厚度(T)、过盈量(I_(ntf))、锥角长边(α_(x))和收缩比(R_(atio))。基于此,利用移动最小二乘法(MLSM)构建峰值力(PCF)、比吸能(SEA)和平均力(MCF)的近似模型。主效应分析表明,收缩比对PCF、SEA和MCF的影响最为显著。以获取最小PCF、最大SEA以及MCF最接近设计要求650 kN为优化目标,进行全局响应面(GRSM)优化,获得最优结构配置,与初始设计相比,SEA提高28.54%,PCF降低12.37%。代理模型最优解得出的MCF与有限元模型误差为2.01%,证明构建的代理模型具有较高的精度,可用于优化计算。优化后的结构有效提高了收缩管的吸能能力,降低了碰撞的初始峰值力。 展开更多
关键词 收缩管 过盈配合 耐撞性设计 结构参数分析 多目标优化
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强化换热管冷却壁传热分析及结构优化 被引量:1
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作者 徐迅 吴俐俊 《湖南工业大学学报》 2024年第4期13-19,共7页
强化冷却水管的换热,对提高冷却壁的传热性能、延长冷却壁使用寿命有重要意义。利用Fluent数值模拟研究了丁胞管、螺纹管、扭曲椭圆管3种强化换热管对冷却壁换热性能的影响,并对强化换热管结构参数进行了优化,建议丁胞管结构参数设定如... 强化冷却水管的换热,对提高冷却壁的传热性能、延长冷却壁使用寿命有重要意义。利用Fluent数值模拟研究了丁胞管、螺纹管、扭曲椭圆管3种强化换热管对冷却壁换热性能的影响,并对强化换热管结构参数进行了优化,建议丁胞管结构参数设定如下:丁胞纵向间距为40 mm,径向丁胞数为4,丁胞半径为2 mm;螺纹管结构参数设定肋条数为4,肋高为1 mm,肋宽为5~7 mm,导程为25~40 mm;扭曲椭圆管结构参数设定导程不大于100 mm,短长轴之比取0.4~0.6。对比分析实验结果表明:螺纹管和扭曲椭圆管对冷却壁强化换热效果较好,丁胞管较差,扭曲椭圆管可以在水管压力损失较小下实现较好的强化换热效果。 展开更多
关键词 冷却壁 强化换热管 数值模拟 结构优化
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乌兹别克斯坦9度区某超高层建筑结构设计与优化 被引量:1
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作者 闫锋 花炳灿 安东亚 《建筑结构》 北大核心 2024年第13期51-56,共6页
对于9度设防地区的超高层建筑,其结构设计基本由地震作用控制,因此抗震设计尤为重要。建筑消能减震技术可在提高结构地震安全储备的同时,降低整体工程造价,是结构优化设计的有效措施。对位于9度区的超高层建筑进行了结构方案选型对比、... 对于9度设防地区的超高层建筑,其结构设计基本由地震作用控制,因此抗震设计尤为重要。建筑消能减震技术可在提高结构地震安全储备的同时,降低整体工程造价,是结构优化设计的有效措施。对位于9度区的超高层建筑进行了结构方案选型对比、结构方案优化、减震设计方案比选、剪力墙内嵌钢板优化。结果显示,钢骨混凝土框架⁃核心筒方案相对于钢框架⁃支撑方案具备更高的成本优势;框架⁃核心筒方案可通过精细化设计作进一步优化;在此基础上,对钢骨混凝土框架⁃核心筒方案采用两种消能减震方案进行比选,结果表明,采用黏滞阻尼器方案的结构抗震性能明显优于采用黏滞阻尼墙方案;最后通过增大剪力墙竖向分布钢筋配筋率,对低区核心筒墙肢中的内嵌钢板进行了优化。 展开更多
关键词 9度抗震设防 超高层建筑 钢骨混凝土结构 框架⁃核心筒 消能减震
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设有叠合柱的局部错层RC框架结构地震易损性分析 被引量:1
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作者 张淑云 刘建波 +2 位作者 代慧娟 王乐 高欣悦 《中国科技论文》 CAS 2024年第3期275-283,共9页
为研究某一设有叠合柱的局部错层钢筋混凝土(reinforced concrete,RC)框架结构在近断层和远场地震作用下的破坏概率,自定义钢管混凝土叠合柱塑性铰参数,并与试验对比验证塑性铰参数的有效性。采用SAP2000建立非线性分析模型,选取近断层... 为研究某一设有叠合柱的局部错层钢筋混凝土(reinforced concrete,RC)框架结构在近断层和远场地震作用下的破坏概率,自定义钢管混凝土叠合柱塑性铰参数,并与试验对比验证塑性铰参数的有效性。采用SAP2000建立非线性分析模型,选取近断层和远场地震波共22条,分别以地震峰值加速度(peak ground acceleration,PGA)和最大层间位移角作为地震动强度指标和结构性能指标,基于增量动力分析(incremental dynamic analysis,IDA)结果和点估计函数对错层框架结构进行易损性分析。结果表明:对于远场地震动,结构满足“三水准”抗震设防要求,在罕遇地震下超越防止倒塌极限状态的概率仅为0.24%;结构在近断层多遇地震下仍能满足“小震不坏”的设计要求,设防地震下结构超越修复后使用极限状态的概率为53.63%,发生中等破坏的概率较大,罕遇地震下结构达到倒塌极限状态的概率为5.37%,较远场地震作用破坏更为严重。研究结果可为错层框架结构的设计和地震风险评估提供参考。 展开更多
关键词 近断层地震 错层框架结构 钢管混凝土叠合柱 增量动力分析 点估计
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考虑“筒中筒”耦合作用的深水隔水管柱与钻柱碰摩运动规律
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作者 狄勤丰 骆大坤 +2 位作者 秦垦 王文昌 陈锋 《石油钻采工艺》 CAS 北大核心 2024年第1期25-32,共8页
深水钻井时,旋转钻柱与海洋环境力作用下发生振动的隔水管柱易发生接触,造成钻柱与隔水管柱的碰撞或者摩擦。为了解隔水管柱与钻柱间的运动状态,减轻两者间碰摩,保证作业安全性,提出了一种模拟深水隔水管柱-钻柱组成的“筒中筒”耦合系... 深水钻井时,旋转钻柱与海洋环境力作用下发生振动的隔水管柱易发生接触,造成钻柱与隔水管柱的碰撞或者摩擦。为了解隔水管柱与钻柱间的运动状态,减轻两者间碰摩,保证作业安全性,提出了一种模拟深水隔水管柱-钻柱组成的“筒中筒”耦合系统模型,通过分析二者间的位移与接触力,实现海洋深水钻井作业时隔水管柱与钻柱的耦合动力学模拟的建立。模拟结果表明,考虑隔水管柱与钻柱接触的情况下,海流作用和涡激作用对钻柱的动力学特征具有较大影响;海流速度增加,隔水管柱弯曲程度变大,隔水管柱的振动特征会限制钻柱运动;井口转速增加对钻柱的涡动特征影响小,但会增大钻柱与隔水管柱内壁的接触力,增大钻柱与隔水管柱的失效风险。该理论为海洋深水钻井摩阻分析提供了新的借鉴。 展开更多
关键词 深水钻井 钻柱动力学 “筒中筒”耦合结构 隔水管柱-钻柱耦合振动 接触碰撞
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基于p阶线性模型的地埋管换热器流体温度分布研究
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作者 赵鹏 张东海 +3 位作者 李晓昭 张古彬 寇亚飞 高蓬辉 《太阳能学报》 EI CAS CSCD 北大核心 2024年第6期51-59,共9页
利用自主研发的分层热响应测试系统,获取沿深度方向上(竖向)管内流体温度实测数据,对比p阶线性分布模型计算结果和实测数据,研究两种典型工况条件下分层岩土介质中管内流体竖向分布规律和最佳p值。结果表明:恒热流工况时,p=-5阶线性分... 利用自主研发的分层热响应测试系统,获取沿深度方向上(竖向)管内流体温度实测数据,对比p阶线性分布模型计算结果和实测数据,研究两种典型工况条件下分层岩土介质中管内流体竖向分布规律和最佳p值。结果表明:恒热流工况时,p=-5阶线性分布模型能够准确预测管内流体温度分布;恒温工况时,最佳p值随流量的变化而变化,其关系为:|p|=7.361ln V+6.684。 展开更多
关键词 地热能 地埋管换热器 岩土传热 地质结构分层 参数估值
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基于回归分析法的矩形槽圆管吸能特性研究
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作者 雷成 李福胜 +1 位作者 缪得祥 朱涛 《机械强度》 CAS CSCD 北大核心 2024年第2期292-300,共9页
为了研究矩形槽圆管吸能特性规律,提出了一种基于回归分析法的结构参数与吸能特性关系的拟合方法。针对轴向冲击下的圆管动态响应,首先,建立了6005A-T6材料的Cowper-Symonds本构模型,并验证了仿真模型的准确性;其次,设计了正交试验,建... 为了研究矩形槽圆管吸能特性规律,提出了一种基于回归分析法的结构参数与吸能特性关系的拟合方法。针对轴向冲击下的圆管动态响应,首先,建立了6005A-T6材料的Cowper-Symonds本构模型,并验证了仿真模型的准确性;其次,设计了正交试验,建立了吸能特性与结构参数之间的计算模型;然后,利用多元线性与非线性回归分析方法对计算模型参数求解,并对比了两种拟合结果,得到了峰值力和吸能量的经验公式;接着,对比经验公式与有限元数值计算值表明,经验公式在研究范围内具有较高准确性,误差在8%以内;最后,引入吸能性能指标并使用遗传算法对圆管进行了结构优化,优化结果表明,在研究范围内当直径和槽端距最小、壁厚和槽宽最大、槽深最浅时,矩形槽圆管的吸能性能最优。 展开更多
关键词 矩形槽 薄壁圆管 多元回归分析法 经验公式 结构优化
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