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Study on Flow Unit of Heavy Oil Bottom Water Reservoir with Over-Limited Thickness in Offshore Oilfield
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作者 Wei Wang Jie Tan +2 位作者 Songru Mu Bo Li Wentong Zhang 《Open Journal of Geology》 2019年第9期507-515,共9页
The upper Ming section of L oilfield is a typical offshore heavy oil bottom-water reservoir with thick fluvial layers. All horizontal wells are developed by natural energy. Due to the few drilling holes and influence ... The upper Ming section of L oilfield is a typical offshore heavy oil bottom-water reservoir with thick fluvial layers. All horizontal wells are developed by natural energy. Due to the few drilling holes and influence by the resolution of seismic data, it is difficult to describe reservoirs with thickness over 20 meters. In this paper, seismic resonance amplitude inversion technology is introduced to restore the real response of thick reservoirs and interbeds by drilling and drilling verification, and the geological bodies with different thickness are displayed by frequency division RGB three primary colors. Flow units of heavy oil reservoirs with bottom water are divided according to the three major factors of interlayer, lithologic internal boundary and water-oil thickness ratio which have the greatest influence on horizontal well development, thick sand bodies are divided into 10 different flow units in three levels, each unit is separated from each other, and the reservoir structure, water-cut characteristics and water-flooding characteristics are different. The reliability of the research is improved by using the dynamic data of horizontal wells and newly drilled passing wells, which provides a basis for tapping the potential of heavy oil reservoirs with bottom water. 展开更多
关键词 Over-Limited THICK Layer INVERSION of Tuned Amplitude Frequency DIVISION RGB Fusion Water-Oil thickness ratio flow Unit
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Optimization Analysis of the Mixing Chamber and Diffuser of Ejector Based on Fano Flow Model
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作者 Lixing Zheng Weibo Wang +2 位作者 Yiyan Zhang Lingmei Wang Wei Lu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第10期153-170,共18页
An improved model to calculate the length of the mixing chamber of the ejector was proposed on the basis of the Fano flow model,and a method to optimize the structures of the mixing chamber and diffuser of the ejector... An improved model to calculate the length of the mixing chamber of the ejector was proposed on the basis of the Fano flow model,and a method to optimize the structures of the mixing chamber and diffuser of the ejector was put forward.The accuracy of the model was verified by comparing the theoretical results calculated using the model to experimental data reported in literature.Variations in the length of the mixing chamber L_(m) and length of the diffuser L_(d) with respect to variations in the outlet temperature of the ejector T_(c),outlet pressure of the ejector p_(c),and the expansion ratio of the pressure of the primary flow to that of the secondary flow p_(g)/p_(e) were investigated.Moreover,variations in L_(m) and L_(d) with respect to variations in the ratio of the diameter of the throat of the motive nozzle to the diameter of the mixing chamber d_(g0)/d_(c3) and ratio of the outlet diameter of the diffuser to the diameter of themixing chamber d_(c)/d_(c3) were investigated.The distribution of flow fields in the ejector was simulated.Increasing L_(m) and d_(c3) reduced T_(c) and p_(c).Moreover,reducing p_(g)/p_(e) or d_(g0)/d_(c3) reduced T_(c) and p_(c).The length of the mixed section L_(m2),which was determined on the basis of the Fano flow model,increased as pg increased and decreased as d_(c3) increased.The mixing length L_(m1),which was considered the primary flow expansion,showed the opposite trend with that of L_(m2).Moreover,Ld increased as p_(g)/p_(e) and d_(c)/d_(c3) increased.When the value of d_(c) was 1.8 to 2.0 times as high as that of dc3,the semi-cone angle of the diffuser ranged between 6°and 12°.At a constant dc/dc3,decreasing T_(c) and pc increased Ld. 展开更多
关键词 Mixing chamber length Fano flow DIFFUSER diameter ratio expansion ratio optimization method
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Turbulent Modulation in Particulate Flow: A Review of Critical Variables 被引量:1
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作者 Ammar Saber T.Staffan Lundstrom J.Gunnar I.Hellstrom 《Engineering(科研)》 2015年第10期597-609,共13页
A review of the main mechanisms influencing turbulent modulation in the presence of spherical and non-spherical particles is presented. The review demonstrates the need for more numerical and experimental work with hi... A review of the main mechanisms influencing turbulent modulation in the presence of spherical and non-spherical particles is presented. The review demonstrates the need for more numerical and experimental work with higher accuracy than obtained so far and the need to resolve the flow near the surface of particles with the aim to re-evaluate the quantitative effect of different parameters on turbulent modulation. The review reveals that non-spherical particles have more adverse effect on turbulence as compared to spherical ones, for the same ambient conditions. 展开更多
关键词 Two Phase flow Turbulent Modulation Non-Spherical Particle Stokes Number Particle Reynolds Number length Scale Density ratio
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Numerical investigation of cavity flow at subsonic and transonic speeds
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作者 雷娟棉 郑志伟 周奇 《Journal of Beijing Institute of Technology》 EI CAS 2014年第1期16-23,共8页
Based on finite volume method, subsonic and transonic flow in 3-D cavity of different length-to-depth ratios are numerically investigated by using Navier-Stokes equations with k-ε SST two-equation turbulence model an... Based on finite volume method, subsonic and transonic flow in 3-D cavity of different length-to-depth ratios are numerically investigated by using Navier-Stokes equations with k-ε SST two-equation turbulence model and coupled implicit algorithm. The cavity streamline patterns and the static pressure coefficient distributions on the cavity floor are shown, and the flow characteristics of the cavity and the floor pressure coefficient distributions are analyzed. Numerical results demon- strate that the flow characteristics of the cavity at subsonic and transonic speeds are different from that of supersonic ones; length-to-depth ratio is the main factor that affects the flow characteristics of the cavity at subsonic and transonic number has a neglectable effect on the cavity floor pressure distributions. speeds and causes changes of the cavity flow type; Mach cavity flow fields at subsonic and transonic speeds and the 展开更多
关键词 cavity flow numerical simulation length-to-depth ratio Mach number
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基于CFD流场模拟的大型卧式反应釜结构研究
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作者 袁爱武 黄金豪 《有色设备》 2024年第3期58-63,共6页
近年来,加压浸出湿法冶金工程在向更大规模的发展道路受到了配套装备大型化带来的技术制约。为了适应加压浸出工艺关键核心设备-卧式反应釜的规模大型化发展,更好地保证该设备在使用过程中的可靠性与高效性。本文采用CFD流体模拟软件,... 近年来,加压浸出湿法冶金工程在向更大规模的发展道路受到了配套装备大型化带来的技术制约。为了适应加压浸出工艺关键核心设备-卧式反应釜的规模大型化发展,更好地保证该设备在使用过程中的可靠性与高效性。本文采用CFD流体模拟软件,针对某项目使用的300立卧式反应釜,研究其在不同长径比下的流场分布情况以及搅拌器功率消耗大小与长径比的关系。研究表明适当增加长径比有利于改善水平方向的流场特性,减小长径比有利于改善垂直方向的流场特性,减小长径比有利于搅拌功率的降低。当长径比取1.08或1.13,能够有效提高卧式反应釜内的反应效率,降低成本和系统能耗。 展开更多
关键词 卧式反应釜 长径比 流场分布 功率消耗 CFD 数值模拟
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不同截面类型玻纤增强PA6的性能
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作者 孟凡地 吴承然 +3 位作者 易琪伟 王彩 孙照亮 邓娇 《工程塑料应用》 CAS CSCD 北大核心 2024年第7期43-48,共6页
对比研究了扁平玻纤及圆形玻纤增强尼龙6 (PA6)复合材料的力学性能、流动性能、收缩翘曲情况、摩擦性能及线膨胀系数(CLTE)。结果表明,随着玻纤含量增加,扁平玻纤及圆形玻纤增强PA6复合材料力学性能均增加,但熔体流动速率(MFR)降低;相... 对比研究了扁平玻纤及圆形玻纤增强尼龙6 (PA6)复合材料的力学性能、流动性能、收缩翘曲情况、摩擦性能及线膨胀系数(CLTE)。结果表明,随着玻纤含量增加,扁平玻纤及圆形玻纤增强PA6复合材料力学性能均增加,但熔体流动速率(MFR)降低;相同玻纤含量下,与圆形玻纤相比,扁平玻纤增强PA6复合材料的拉伸强度、弯曲强度及弯曲弹性模量较低,简支梁缺口冲击强度及MFR较高。在玻纤含量30%的条件下,不同扁平玻纤及圆形玻纤增强PA6复合材料性能存在差异,通过收缩率测试分析,扁平玻纤复合材料比圆形玻纤具有更低的收缩率及横纵收缩比,扁平比越高,横纵收缩比越低,翘曲度越小;通过MFR及注塑螺旋线测试,发现扁平玻纤复合材料具有更好流动性、更高流长比,扁平比越高优势越明显,有利于成型加工;通过滑动摩擦测试结果看出,扁平玻纤复合材料具有更低摩擦系数,随着扁平比增大,摩擦系数越低;通过热机械分析检测,扁平玻纤复合材料在垂直流动方向CLTE低于圆形玻纤,且流动方向和垂直流动方向CLTE差异也较小。扁平玻纤增强材料能改善传统圆形玻纤增强体系的一些不足,优化产品性能。 展开更多
关键词 尼龙6 扁平玻纤 收缩率 流长比 线膨胀系数
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基于FLOW-3D软件的深井膏体管道自流输送性能 被引量:20
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作者 王新民 张德明 +1 位作者 张钦礼 赵彬 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第7期2102-2108,共7页
基于工程流体力学、统计学、管道自流输送等相关理论,结合金川龙首矿西部充填系统的实际情况,开发运用FLOW-3D软件,对膏体自流输送充填系统不同充填倍线条件下的管道工作特性进行数值模拟与分析。研究结果表明:随着充填倍线(N)的增加,... 基于工程流体力学、统计学、管道自流输送等相关理论,结合金川龙首矿西部充填系统的实际情况,开发运用FLOW-3D软件,对膏体自流输送充填系统不同充填倍线条件下的管道工作特性进行数值模拟与分析。研究结果表明:随着充填倍线(N)的增加,充填系统管道进口、出口压力不断减少,而整个系统的总压力基本保持不变;当N<3.0时料浆出口剩余压力过大,N≥3.5时管道压力损失过大;当N>3.5时充填系统的流速比较接近膏体的临界流速;在稳定状态下,随着膏体流速的减慢,管道弯管连接处的局部压力损失逐步减小,而当N>3.0且流速继续减小时,压力损失却随之增加。因此,综合考虑各充填倍线在流速、压力损失、流量以及弯管处压力损失,以低成本、高效率为原则,最终确定西部膏体自流充填系统满管流状态下的最优充填倍线N=3.0。 展开更多
关键词 膏体充填 自流输送 充填倍线 数值分析
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Effects of Traditional Chinese Herbal Medicine on the Structure of Duodenal Mucosa of Chickens under Heat Stress 被引量:1
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作者 高桂生 陈娟 +5 位作者 刘欢 邢超 史秋梅 沈萍 高光平 张艳英 《Agricultural Science & Technology》 CAS 2015年第1期103-106,146,共5页
[Objective] This study aimed to investigate the effects of traditional Chinese herbal medicine on the structure of duodenal mucosa of chickens under heat stress. [Method] One hundred and twenty 88-day-old Isa Brown ch... [Objective] This study aimed to investigate the effects of traditional Chinese herbal medicine on the structure of duodenal mucosa of chickens under heat stress. [Method] One hundred and twenty 88-day-old Isa Brown chickens were randomly divided into six groups, including three control groups (normal temperature control group, high temperature control group, high temperature Vc control group) and three high-temperature administration groups (high-dose administration group, moderate-dose administration group, low-dose administration group). Chickens in normal temperature control group were reared at 14-25 ℃, and those in other five groups were reared at 28-39 ℃. The experiment lasted 10 d. Five chickens in each group were euthanized at 1, 4, 8 and 10 d post-treatment, respectively. The duodenal mucosa was collected and prepared into tissue slices with the conventional method for hematoxylin-eosin (HE) staining. Mucosal thickness, villus length and crypt depth of duodenal mucosa were measured. [Result] Under heat stress, duodenal mucosal thickness and villus length were both significantly lower than those in normal temperature control group, and the duodenal villi were scarce and thin. However, under high temperature conditions, various indicators in high-dose and moderate-dose administration groups were higher than those in high temperature control group and high temperature Vc control group, which exhibited extremely significant differences at 8 and 10 d post-treatment, especially. Moreover, various indicators in high-dose administration group were significantly higher than those in moderate-dose and low-dose administration groups. The traditional Chinese herbal medicine prescription exhibited higher protective effects on duodenal mucosa of chickens under heat stress compared with high temperature Vc control group. [Conclusion] Under heat stress, traditional Chinese herbal medicine reduced effectively the duodenal mucosa damage in chickens. 展开更多
关键词 Traditional Chinese herbal medicine Heat stress Mucosal thickness Villus length Villus length to crypt depth ratio
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爆炸动载下金属柱壳破片速度场分布研究
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作者 朱建军 霍宪旭 李伟兵 《南京理工大学学报》 CAS CSCD 北大核心 2024年第2期148-154,174,共8页
针对格尼(Gurney)公式无法描述破片速度场沿圆柱壳体轴向变化的问题,该文通过AUTODYN软件建立仿真模型,分析了长径比和壳体壁厚对破片速度场分布的影响。考虑爆炸加载下壳体断裂过程,修正了Gurney公式。基于上述研究,将壳体长径比和相... 针对格尼(Gurney)公式无法描述破片速度场沿圆柱壳体轴向变化的问题,该文通过AUTODYN软件建立仿真模型,分析了长径比和壳体壁厚对破片速度场分布的影响。考虑爆炸加载下壳体断裂过程,修正了Gurney公式。基于上述研究,将壳体长径比和相对壁厚引入指数形式的修正因子中,建立了破片速度场轴向分布模型。通过实验验证了该模型的合理性。研究结果表明:对于圆柱形战斗部,相对壁厚为常数,长径比越大,战斗部形成破片速度越接近v 0;长径比为常数,壳体相对壁厚越小,战斗部形成破片速度越接近v 0。将该文理论结果与Gurney理论结果以及实验结果进行对比,该文理论结果误差均在7%以内,大部分误差小于3%,与实验结果更加吻合,验证了该文建立的破片速度场轴向分布模型的合理性。该文理论模型可为杀伤战斗部破片参数精准设计提供参考。 展开更多
关键词 破片速度 格尼公式 圆柱壳体 壁厚 长径比 数值模拟
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花岗岩山坡A-C结构土壤下典型植被优先流发育特征研究
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作者 曾敏 杨倩 +3 位作者 吴元芝 王月月 安娟 姚光兴 《山东林业科技》 2024年第4期1-10,19,共11页
土石山区A-C结构土壤条件下土薄石多,不同植被条件下优先流发育的是否受到土壤厚度、石砾含量的影响尚不明确。本研究利用染色示踪法与图像处理技术,对鲁中南花岗岩山坡2种土层厚度条件下的黑松林、刺槐林(土层厚度约为40 cm)和板栗林(... 土石山区A-C结构土壤条件下土薄石多,不同植被条件下优先流发育的是否受到土壤厚度、石砾含量的影响尚不明确。本研究利用染色示踪法与图像处理技术,对鲁中南花岗岩山坡2种土层厚度条件下的黑松林、刺槐林(土层厚度约为40 cm)和板栗林(土壤厚度约为80 cm)优先流染色剖面分布特征及其影响因素进行研究。结果表明,3种植被覆盖下基质流发育深度和最大入渗深度非均匀系数差异不显著(P>0.05),但土层较厚的板栗林最大入渗深度、优先流比、长度指数均明显较高(P<0.05),因此土层较厚条件下优先流发育程度较高。根长密度、土壤容重、总孔隙度、非毛管孔隙度、石砾含量,是影响各植被条件下优先流路径选择的重要因素,但土壤物理性质和根系的剖面分布变化是影响不同植被条件下优先流发育差异的关键因素。研究结果有助于进一步揭示土石山区优先流产流机制。 展开更多
关键词 优先流 染色示踪 染色面积比 土壤厚度 植被类型
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热镀锌沉没辊系粘滞阻力及其影响因素研究
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作者 钱胜 曹建华 +2 位作者 刘格非 顾清 王孝建 《铜陵学院学报》 2024年第3期104-109,共6页
针对沉没辊系所受锌液粘滞阻力无法获取的问题,首先分析粘滞阻力影响机理和影响因素,根据辊及带钢的运动特性划分边界层,构建沉没辊系粘滞阻力新模型,通过改变辊插入量调控辊转动状态来反求边界层粘滞阻力,最后将该模型应用于某镀锌机... 针对沉没辊系所受锌液粘滞阻力无法获取的问题,首先分析粘滞阻力影响机理和影响因素,根据辊及带钢的运动特性划分边界层,构建沉没辊系粘滞阻力新模型,通过改变辊插入量调控辊转动状态来反求边界层粘滞阻力,最后将该模型应用于某镀锌机组。结果表明,两种规格带钢在锌锅内各分区粘滞阻力计算误差都在15%范围内满足机组要求;在实际工况下,带钢与锌液速度差对锌液粘滞阻力影响呈现非线性递增规律,锌液粘滞阻力随带钢表面镀锌量增加而呈现非线性递减趋势但其波动幅度不同,而锌液粘滞阻力随带钢与锌液的温差递增呈现不同程度下降趋势。 展开更多
关键词 热镀锌 带钢区段 粘滞阻力新模型 边界层厚度 过流长度
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对《砌体结构设计规范》中高厚比修正系数等问题的探讨
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作者 汪冬生 《江苏建筑》 2024年第3期45-48,58,共5页
文章指出了《砌体结构设计规范》(GB 50003—2011)中关于带门窗洞口砌体墙允许高厚比的修正系数μ2的计算精度不足,并根据弹性稳定理论,提出了两端铰接变截面柱临界荷载Pcr的正确表达式,通过理论计算和有限元模拟对其给予了证明,此外,... 文章指出了《砌体结构设计规范》(GB 50003—2011)中关于带门窗洞口砌体墙允许高厚比的修正系数μ2的计算精度不足,并根据弹性稳定理论,提出了两端铰接变截面柱临界荷载Pcr的正确表达式,通过理论计算和有限元模拟对其给予了证明,此外,还推导了门窗洞口最不利布置时的μ2表达式。在此基础上,提出了比《砌体结构设计规范》(GB 50003—2011)更合理的有洞口墙体的允许高厚比修正系数μ2计算公式,同时对μ2的相关应用细则提出了修正建议。以修正后的两端铰接柱临界荷载Pcr为基础,提出了规范中变截面柱下段计算长度H0的更合理形式,为便于工程应用,最后对规范中有吊车房屋变截面柱计算长度的应用条款提出了修改建议。 展开更多
关键词 有洞口砌体墙 两端铰接变截面柱 临界荷载 允许高厚比修正系数 计算长度
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Effect of Width-to-Thickness Ratio and Thickness Profile Changing on the Critical Instable Shape During Cold Strip Rolling 被引量:1
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作者 宋蕾 沈明钢 +2 位作者 杨利坡 王军生 陈雪波 《Journal of Shanghai Jiaotong university(Science)》 EI 2016年第4期411-418,共8页
Based on the volume constancy with equal flow-per-second and elastic sheet stability theory, a coupling relationship among lateral thickness difference, width-to-thickness ratio of cold rolling strip steel under ideal... Based on the volume constancy with equal flow-per-second and elastic sheet stability theory, a coupling relationship among lateral thickness difference, width-to-thickness ratio of cold rolling strip steel under ideal and actual working conditions, and shape is concluded according to the comprehensive influence principle of various factors on the critical instable shape analyzed in-depth. Firstly, the influence model under actual working condition is developed by referring to the basic relationship between lateral thickness difference and shape under ideal condition. The test results prove that for thin strips with thickness below 0.3 mm, their lateral thickness differences have significant effect on the shape. After then, the combined influence of lateral thickness difference and width-to-thickness ratio on the critical instable shape is concluded according to the elastic sheet stability model, with the synthetic effect of these three factors analyzed. Test data indicate that for cold rolling strip steel with width-to-thickness ratio above 3 000, the critical instability stress difference decreases significantly. Actual measurements are conducted on the lateral thickness differences of two rolls of typical strip manufactured by a sixhigh cold mill, with the influence law of lateral thickness variation and width-to-thickness ratio comprehensively investigated. It is demonstrated that during the production of ultrathin strip steel with different width-to-thickness ratios, the loading roll shapes should be fine adjusted according to the lateral thickness difference of input strips.Therefore, the variation of lateral thickness difference of output strips can meet the requirement of shape stability,so as to obtain fine shape. 展开更多
关键词 cold rolling strip lateral thickness difference width-to-thickness ratio sec flow rate equal
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MoldFlow在轿车继电器保险盒盖注射模设计中的应用 被引量:1
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作者 姬和平 许智 《模具制造》 2014年第1期56-59,共4页
介绍了轿车继电器保险盒盖注射模通过MoldFlow模拟分析并确定浇口位置及塑件壁厚改善优化,具体分析浇口位置、数量、壁厚对塑件的填充和缺陷的影响。
关键词 熔接痕 困气 流长比 浇口位置 壁厚
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Parametric study on supersonic flutter of angle-ply laminated plates using shear deformable finite element method
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作者 Wei Xia Qiao Ni 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期749-756,共8页
The influence of fiber orientation,flow yaw angle and length-to-thickness ratio on flutter characteristics of angle-ply laminated plates in supersonic flow is studied by finite element approach.The structural model is... The influence of fiber orientation,flow yaw angle and length-to-thickness ratio on flutter characteristics of angle-ply laminated plates in supersonic flow is studied by finite element approach.The structural model is established using the Reissner-Mindlin theory in which the transverse shear deformation is considered.The aerodynamic pressure is evaluated by the quasi-steady first-order piston theory.The equations of motion are formulated based on the principle of virtual work.With the harmonic motion assumption,the flutter boundary is determined by solving a series of complex eigenvalue problems.Numerical study shows that (1) The flutter dynamic pressure and the coalescence of flutter modes depend on fiber orientation,flow yaw angle and length-to-thickness ratio;(2) The laminated plate with all fibers aligned with the flow direction gives the highest flutter dynamic pressure,but a slight yawing of the flow from the fiber orientation results in a sharp decrease of the flutter dynamic pressure;(3) The angle-ply laminated plate with fiber orientation angle equal to flow yaw angle gives high flutter dynamic pressure,but not the maximum flutter dynamic pressure;(4) With the decrease of length-to-thickness ratio,an adverse effect due to mode transition on the flutter dynamic pressure is found. 展开更多
关键词 Panel flutter Angle-ply laminates Fiber orientation flow yaw angle length-to-thickness ratio
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流离球内填料配比对SBBR污染物去除影响的研究 被引量:1
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作者 王帆 杨凯伦 +3 位作者 康华 蒋维卿 艾胜书 边德军 《水处理技术》 CAS CSCD 北大核心 2023年第11期112-116,127,共6页
为了探究流离球内部组合填料配比对污水中污染物去除的影响,以鲍尔环与海绵作为内部填料,组成7种不同填料配比的流离球,构建SBBR反应器进行实验。鲍尔环与海绵填料体积比分别为:0∶189、4∶27、11∶27、21∶27、37∶27、71∶27、171∶2... 为了探究流离球内部组合填料配比对污水中污染物去除的影响,以鲍尔环与海绵作为内部填料,组成7种不同填料配比的流离球,构建SBBR反应器进行实验。鲍尔环与海绵填料体积比分别为:0∶189、4∶27、11∶27、21∶27、37∶27、71∶27、171∶27。实验结果表明,各填料比下COD处理效果较好,改变组合填料配比主要影响了传质效果、生物膜量、厌氧空间大小进而影响了系统的脱氮性能。填料比为37∶27时氮的去除效果最好,NH_(4)^(+)-N、TN的平均去除率分别为56.4%和55.3%;此时,系统生物量适中,生物膜絮凝性好。 展开更多
关键词 流离球 组合填料配比 序批式生物膜反应器(SBBR) 生物膜厚度
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圆钢管活性粉末混凝土黏结性能有限元分析 被引量:3
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作者 刘晓 周鸣 +1 位作者 侯东序 郁舒敏 《沈阳大学学报(自然科学版)》 CAS 2023年第1期67-73,共7页
为了研究圆钢管与活性粉末混凝土之间的黏结性能,建立了有限元模型,并使用有限元软件ABAQUS分析了试件长细比、径厚比和活性粉末混凝土强度等参数对钢管活性粉末混凝土界面承载能力的影响,剖析了试件运行机制和典型试件的载荷-滑移曲线... 为了研究圆钢管与活性粉末混凝土之间的黏结性能,建立了有限元模型,并使用有限元软件ABAQUS分析了试件长细比、径厚比和活性粉末混凝土强度等参数对钢管活性粉末混凝土界面承载能力的影响,剖析了试件运行机制和典型试件的载荷-滑移曲线。结果显示:初始黏结破坏载荷会随着径厚比的增加而减少,随着活性粉末混凝土强度与长细比的增加而增加;在试件经历极限黏结破坏后,混凝土的各项性能损失严重,曲线呈逐渐下降状态。 展开更多
关键词 钢管活性粉末混凝土 径厚比 长细比 RPC强度 有限元分析
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隧道长度对烟气分布影响数值模拟 被引量:2
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作者 孙振宇 赵维刚 +1 位作者 张耀 郭庆华 《消防科学与技术》 CAS 北大核心 2023年第2期212-216,共5页
采用数值模拟方法,研究隧道长度对火灾烟气质量流量及烟气层厚度的影响。隧道长度分别设定为100,200,300,400,500m。结果发现:设定条件下,烟气蔓延距离大于200m时,烟气沉降明显,烟气质量流量和厚度呈现先增大后变小的趋势;烟气层下方存... 采用数值模拟方法,研究隧道长度对火灾烟气质量流量及烟气层厚度的影响。隧道长度分别设定为100,200,300,400,500m。结果发现:设定条件下,烟气蔓延距离大于200m时,烟气沉降明显,烟气质量流量和厚度呈现先增大后变小的趋势;烟气层下方存在诱导气流,二者之间的剪切作用共同影响烟气质量流量和厚度的变化;200m范围内,诱导气流的速度随着与火源距离的增加而增大,主要是由于烟气层温度较高,浮力效应较强,从而卷吸下层冷空气,导致烟气质量流量和厚度增大,下方诱导气流空间减小,导致速度增加;200m范围外,烟气层温度大幅降低,浮力效应减弱,诱导气流惯性力在二者剪切作用下占据主要作用,从而卷吸上层烟气,导致烟气质量流量和厚度减小。 展开更多
关键词 隧道长度 火灾烟气 烟气层厚度 质量流量 温度
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长宽比对双进水管结构矩形圆弧角养殖池排污特性的影响 被引量:1
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作者 史宪莹 李猛 +5 位作者 任效忠 冯德军 刘航飞 周寅鑫 刘海波 赵晨旭 《大连海洋大学学报》 CAS CSCD 北大核心 2023年第4期707-716,共10页
为探究长宽比参数(即L/W,L为养殖池长边,W为养殖池宽边)对双进水管结构矩形圆弧角养殖池排污特性的影响,构建了固-液两相流数值计算模型(DPM离散项模型与RNG k-ε连续相模型),定义了适用于较大长宽比养殖池排污模拟的粒子重叠撒布方式,... 为探究长宽比参数(即L/W,L为养殖池长边,W为养殖池宽边)对双进水管结构矩形圆弧角养殖池排污特性的影响,构建了固-液两相流数值计算模型(DPM离散项模型与RNG k-ε连续相模型),定义了适用于较大长宽比养殖池排污模拟的粒子重叠撒布方式,在L/W为1.0~1.9工况下,对两种进水管布置方式(进水管布置在长边中心和宽边中心)的养殖池排污效果进行了数值模拟试验。结果表明:L/W=1.0~1.5时,两种进水管布置方式的养殖池内粒子排除率均可达95%以上,随着长宽比的增加,养殖池内的排污效果变差;L/W=1.6~1.8时,进水管布置在长边中心时,未能排除的粒子在养殖池内汇聚更为集中。研究表明,在实际矩形圆弧角养殖池建设过程中,为使养殖池具有良好的排污性能和提高场地利用率,可选择L/W=1.0~1.5的池形进行建造。 展开更多
关键词 长宽比参数 矩形圆弧角养殖池 排污特性 固-液两相流数值模型
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短屈服段屈曲约束支撑的滞回性能研究
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作者 高晨啸 陈向荣 +1 位作者 王欣淼 李刚 《西安建筑科技大学学报(自然科学版)》 北大核心 2023年第6期819-826,共8页
提出短屈服段屈曲约束支撑(SC-BRB),以解决在罕遇地震下钢框架结构残余层间位移角过大导致震后支撑更换困难问题.采用有限元对SC-BRB的滞回性能进行研究,分析参数对支撑的影响规律.结果表明:屈服段长度对BRB的滞回性能影响较大,集中因... 提出短屈服段屈曲约束支撑(SC-BRB),以解决在罕遇地震下钢框架结构残余层间位移角过大导致震后支撑更换困难问题.采用有限元对SC-BRB的滞回性能进行研究,分析参数对支撑的影响规律.结果表明:屈服段长度对BRB的滞回性能影响较大,集中因子α减小后,SC-BRB能较早地进入耗能阶段,拥有更高的耗能效率,但SC-BRB的低周疲劳性能较差;SC-BRB具有足够的耗能能力;增加内核板的宽厚比可减小外约束的用钢量,但宽厚比的增加,会导致支撑低周疲劳性能和延性降低,建议内核宽厚比限值取15;外约束所需的最短长度随着集中因子α的增大而增大,建议取屈服段长度和0.5倍支撑总长中的较大值;建议SC-BRB选取摩擦系数不大于0.1的无粘结材料. 展开更多
关键词 短屈服段屈曲约束支撑 滞回性能 宽厚比 外约束长度 有限元方法
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