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A simple method of depressing numerical dissipation effects during wave simulation within the Euler model 认领
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作者 Zhe Hu Xiaoying Zhang +3 位作者 Weicheng Cui Fang Wang Xiaowen Li Yan Li 《海洋学报:英文版》 SCIE CAS CSCD 2020年第1期141-156,共16页
Numerical wave tanks are widely-acknowledged tools in studying waves and wave-structure interactions. They can generate waves under realistic scales and offers more information on the fluid field. However, most numeri... Numerical wave tanks are widely-acknowledged tools in studying waves and wave-structure interactions. They can generate waves under realistic scales and offers more information on the fluid field. However, most numerical wave tanks suffer from issues known as the numerical dissipation and numerical dispersion. The former causes wave energy to be slowly dissipated and the latter shifts wave frequencies during wave propagation. This paper proposes a simple method of depressing numerical dissipation effects on the basis of solving Euler equations using the finite difference method(FDM). The wave propagation solutions are solved analytically taking into account the influence of the damping terms. The main idea of the method is to append a source term to the momentum equation, whose strength is determined by how strong the numerical damping effect is. The method is verified by successfully depressing numerical effects during the simulation of regular linear waves, Stokes waves and irregular waves. By applying the method, wave energy is able to be close to its initial value after long distance of travel. 展开更多
关键词 NUMERICAL DISSIPATION NUMERICAL WAVE tank WAVE simulation NUMERICAL DAMPING reduction finite difference METHOD
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Numerical Study on NOx Emissions of Methane Re-Combustion in a 600 MWe Coal-Fired Boiler 认领
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作者 Xiaotao Zhang Hussain Ahmad Madni Gondal +4 位作者 Foyuan Duan Weidong Zhang Haoliang Mu Chengyu Zhang Aijun Wang 《能源与动力工程(英文)》 2020年第3期101-107,共7页
The fuel staging combustion technology is a promising low NOx combustion technology for coal-fired boiler. In order to reduce NOx emissions, the burners of a 600?MWe coal-fired boiler are retrofitted in which methane ... The fuel staging combustion technology is a promising low NOx combustion technology for coal-fired boiler. In order to reduce NOx emissions, the burners of a 600?MWe coal-fired boiler are retrofitted in which methane gas is selected as a secondary fuel for re-combustion. The CFD models of combustion process are built to investigate?effects of the methane gasratio on combustion process and NOx emissions. A total of 4 cases are numerically studied, including the pure coal combustion case, the coal combustion with 7.5%, 10%, 12.5% of methane gas re-combustion cases respectively. The results show that the re-combustion of methane can reduce the temperature at primary combustion zone, but increase the temperatures at the re-combustion area and the furnace outlet. The NOx concentration at the furnace outlet reduces with the increasing methane gas ratio.?Methane re-combustion can greatly benefit to the NOx emissions reduction. 展开更多
关键词 NUMERICAL Simulation Re-Combustion NOx EMISSION Reduction
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急冷塔运行工况参数的数值模拟分析 认领
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作者 郭慧媛 《广州化工》 CAS 2020年第9期122-123,185,共3页
固体废物焚烧烟气急冷塔是控制二噁英类污染的一种常用设备,急冷塔的液滴蒸发效率和降温效果是抑制二噁英生成的关键因素。利用fluent软件对急冷塔进行气-液两相流的数值模拟试验研究。模拟计算喷射锥角、液滴直径和喷水量、烟气量及入... 固体废物焚烧烟气急冷塔是控制二噁英类污染的一种常用设备,急冷塔的液滴蒸发效率和降温效果是抑制二噁英生成的关键因素。利用fluent软件对急冷塔进行气-液两相流的数值模拟试验研究。模拟计算喷射锥角、液滴直径和喷水量、烟气量及入口温度等运行参数,最终总结出该急冷塔的运行操作范围;确定喷嘴型号和操作范围;喷水量范围为0.4~0.5 kg/s,急冷塔适用的烟气工况范围。 展开更多
关键词 FLUENT 急冷塔 数值模拟 运行参数优化
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Calculation of Surrounding Rock Pressure of Undercut Subway Station Based on Multi-Factor Affecting Pressure Arch Theory 认领
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作者 Bin Shang Xiaoguang Jin +2 位作者 Guiyong Ao Qiao Chen Qiong Qiu 《工程(英文)(1947-3931)》 2020年第2期59-70,共12页
The formation mechanism of surrounding rock pressure in large-section tunnels of underground excavation is still unclear. The traditional methods for calculating surrounding rock pressure have certain limitations. Bas... The formation mechanism of surrounding rock pressure in large-section tunnels of underground excavation is still unclear. The traditional methods for calculating surrounding rock pressure have certain limitations. Based on the theory of pressure arch and parameter sensitivity analysis, the internal and external boundaries of the pressure arch are solved by numerical simulation. The loose pressure is obtained according to the distance from the inner boundary to the inner wall of the tunnel. The pressure arch deformation is analyzed based on the Winkler model. The surrounding rock pressure is calculated, and the surrounding rock pressure based on the pressure arch theory is calculated. The calculation method of surrounding rock pressure based on the pressure arch theory large section tunnel is proposed. The orthogonal experimental design method was used to select four representative factors: tunnel depth H, span B, internal friction angle φ and rock weight γ. The calculation results of each group of experiments were compiled and multivariate linear regression was used. The method is statistically analyzed, and finally, the calculation formula of the surrounding rock pressure of the large-section tunnel affected by multiple factors is obtained and applied to the calculation of the surrounding rock pressure of the metro station. 展开更多
关键词 PRESSURE ARCH THEORY Sensitivity Analysis SURROUNDING Rock PRESSURE Orthogonal Test Numerical Simulation
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Study of Internal Waste Dump-Induced Shear Stress Behavior on Pit-Slope 认领
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作者 Sugeng Wahyudi Hideki Shimada +5 位作者 Takashi Sasaoka Akihiro Hamanaka Tsedendorj Amarsaikhan Pisith Mao Tumelo K. M. Dintwe Dyson Moses 《地球科学和环境保护期刊(英文)》 2020年第4期71-86,共16页
Regardless of beneficial associated with internal waste dump (IWD) method, practices of this method within boundaries of pit-slope have some serious problems on stability issues due to this area is zone of potential f... Regardless of beneficial associated with internal waste dump (IWD) method, practices of this method within boundaries of pit-slope have some serious problems on stability issues due to this area is zone of potential failure. This zone is known as dynamic reactive zone which is easy to deform by external force, and inherent dangers of failure posing a threat to slope. Therefore, it is paramount to study the induced shear stress behavior in this zone particularly when IWD method is adopted within this zone. In this paper, a numerical study for investigating IWD-induced shear stress behavior has been carried out using Finite Element Method (FEM) with Strength Reduction approach. Different scenarios as per pit-slope depths, IWD heights and buffer zone lengths have been accounted and simulated using PHASE 2 to understand changes in induced shear stress imposed on the pit-slope. It is found that shear stress imposed on pit slope seems change dramatically with increasing IWD height for case of buffer zone length is less than 100-m-long. 展开更多
关键词 SLOPE Stability INTERNAL WASTE DUMP SHEAR-STRESS Numerical Simulation
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Numerical Simulation of the Relationship between the Width of Destressed Zone and Blasthole Depth 认领
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作者 Jiansheng Tian Qingru Wu Zhijun Liu 《工程(英文)(1947-3931)》 2020年第4期269-279,共11页
Overstress in the surrounding rock of the roadway is a key reason that causes failures of deep roadways. Destressing blasting is one of the promising techniques that could improve the supporting quality. If the depth ... Overstress in the surrounding rock of the roadway is a key reason that causes failures of deep roadways. Destressing blasting is one of the promising techniques that could improve the supporting quality. If the depth of the pressure relief blast hole is too shallow, the surrounding rock of the roadway will be broken or even collapsed. If the pressure relief blast hole is too deep, the pressure relief area will be located in the deep part of the surrounding rock of the roadway, which cannot achieve the purpose of releasing the stress in the shallow part of the surrounding rock and cause waste of the blast hole. The width or range of the pressure relief area should just fall in the high stress area of the surrounding rock of the roadway, so the pressure relief blast hole should have a reasonable depth. In order to quantitatively describe the relationship between borehole depth and the width of the stress relief zone, numerical simulations were carried out in ANSYS according to different borehole depths. The results show that the optimal destressing effect is achieved when borehole depth is 4 m. Peak stress of and is significantly reduced by 30.51% and 49.07% after blasting. Meanwhile, the high-stress area shifts about 4.8 m from the roadside to the depth of surrounding rock, thus a 3.8 m wide stress relief zone is formed around the roadside, thus, the aim of quantizing the effects of destress blasting is achieved. 展开更多
关键词 Rock BURST Deep ROADWAY Supporting WIDTH of Stress RELIEF ZONE Destress BLASTING Numerical Simulation
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A Simplified Numerical Approach for Simulating Electromagnetic Propulsion 认领
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作者 Kaichen Wang Ruiwen Chen 《电磁分析与应用期刊(英文)》 2020年第1期1-5,共5页
Electromagnetic propulsion provides a non-contact way for delivering goods. The projectile typically does not contain explosives, which has apparent advantages over traditional methods. Due to the multi-physics nature... Electromagnetic propulsion provides a non-contact way for delivering goods. The projectile typically does not contain explosives, which has apparent advantages over traditional methods. Due to the multi-physics nature, simulation is expensive and time-consuming. We established a simplified model in time domain incorporating mechanics and electromagnetics to study electromagnetic propulsion. Results show that important physical parameters such as force, velocity, acceleration, etc. can be extracted from the model without time-consuming efforts. We hope this model could help the exploration of electromagnetic propulsion. 展开更多
关键词 ELECTROMAGNETIC PROPULSION GAUSSIAN LAW NUMERICAL Simulation
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Experimental and Numerical Investigation of Swirling Flow on Triple Elbow Pipe Layout 认领
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作者 Hideharu Takahashi San Shwin +2 位作者 Ari Hamdani Nobuyuki Fujisawa Hiroshige Kikura 《流量控制、测量及可视化(英文)》 2020年第2期45-62,共18页
The secondary flow downstream of a triple elbow layout was studied experimentally and numerically to visualize the flow behavior under swirling inlet flow conditions. The inlet swirling condition was generated by a sw... The secondary flow downstream of a triple elbow layout was studied experimentally and numerically to visualize the flow behavior under swirling inlet flow conditions. The inlet swirling condition was generated by a swirl generator, consisting of a rotary pipe and honeycomb assembly. The experiments were carried out in turbulent water flow condition at Reynolds number Re = 1 × 104 and inlet swirl intensity S = 1. Ultrasonic measurements were taken at four locations downstream of the third elbow. The two-dimensional velocity field of the flow field was measured using the phased array ultrasonic velocity profiler technique to evaluate the flow field with separation. Furthermore, a numerical simulation was performed and its results were compared with the experimental data. The numerical result was obtained by solving three-dimensional, Reynolds-averaged Navier-Stokes equations with the renormalization group k-ε turbulence model. The experimental results confirmed that the swirling flow condition modified the size of the separation region downstream of the third elbow. A qualitative comparison between the experimental and CFD simulation results of the averaged velocity field downstream of the third elbow showed similar tendency on reverse flow. 展开更多
关键词 Swirling Flow TRIPLE ELBOW ULTRASOUND Phased ARRAY Sensor VELOCITY Profile CFD Numerical Simulation
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Study on the Effective Range of Local Ventilation in the Driving Face of Single Head Roadway 认领
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作者 Yuanwei Hao Yong Wang 《世界工程和技术(英文)》 2020年第1期50-59,共10页
The traditional research considers that the effective range of forced local ventilation in single head tunnel is the horizontal distance from the jet exit section to the rotary section, but there is a low wind speed a... The traditional research considers that the effective range of forced local ventilation in single head tunnel is the horizontal distance from the jet exit section to the rotary section, but there is a low wind speed area at the end of the range which can not completely and effectively release toxic and harmful gases. In this area, due to the small jet energy, there is no way to effectively remove the toxic and harmful gases produced in the driving process, which seriously affects the safety of the mine.?Therefore, the reasonable definition of the effective range of the forced local ventilation of the single head tunnel can not only improve the theory of the local ventilation of the mine, but also prevent the accumulation of gas and ensure the life safety of the employees. In this paper, the definition of effective range of local ventilation in single head heading face is put forward, and the rationality of the definition of effective range is verified by numerical simulation. On the basis of reasonable definition of effective range, the relationship between wind speed and effective range under different ventilation modes is studied by numerical simulation. The results show that when the wind speed at the outlet of the air duct is less than 20 m/s, the effective range changes rapidly with the outlet wind speed, and after more than 20 m/s, the effect of wind speed on the effective range is gradually weakened. Under the same exit wind speed, the effective range of parallel and coplanar air inlet is much greater than that of single air inlet. 展开更多
关键词 EFFECTIVE RANGE Numerical Simulation TUNNELING Ventilation WIND SPEED Ventilation Pattern
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典型山丘地形与风力机诱导涡流耦合演变规律 认领
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作者 史俊杰 许昌 +3 位作者 雷娇 李林敏 薛飞飞 韩星星 《机械工程学报》 EI CAS CSCD 北大核心 2020年第4期85-94,共10页
风电场空气动力场是以涡流形式产生和演变,采用能够提供涡流演变细节特征的大涡模拟(Large eddy simulation,LES)方法模拟典型山丘地形的涡流结构,通过风洞试验数据验证湍动能输运(Kinetic energy transport,KET)模型模拟结果的准确性,... 风电场空气动力场是以涡流形式产生和演变,采用能够提供涡流演变细节特征的大涡模拟(Large eddy simulation,LES)方法模拟典型山丘地形的涡流结构,通过风洞试验数据验证湍动能输运(Kinetic energy transport,KET)模型模拟结果的准确性,并探讨不同入流风速对山丘地形风电场瞬时特性的影响。随后探索地形诱导涡与风力机尾涡耦合的时空演化机制,发现单台风力机与两台并列风力机工况的尾涡结构的耦合演变机理存在差异,单台风力机工况是由于二次涡的形成及其与尾涡的耦合作用,两台并列风力机则归因于二次涡与尾涡的耦合及两机组间涡流耦合的共同作用。针对复杂地形涡流演变的研究可以为风电场规划设计与运行提供参考。 展开更多
关键词 致动盘 涡流耦合 大涡模拟(Large eddy simulation LES) 数值模拟
基于中尺度数值大气模式的海雾特征参数研究 认领
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作者 龙胤宇 陈慧敏 +1 位作者 王凤杰 陆长平 《兵工学报》 EI CAS CSCD 北大核心 2020年第3期507-516,共10页
为了研究掠海激光类武器在海雾气溶胶环境下的回波特性,需要进一步获取海雾气溶胶的特征参数。基于中尺度数值大气模式的天气研究与预报模型,在垂直空间针对海雾所在空间区域设置更为密集的η分层,对2015年4月28日~2015年4月29日的渤海... 为了研究掠海激光类武器在海雾气溶胶环境下的回波特性,需要进一步获取海雾气溶胶的特征参数。基于中尺度数值大气模式的天气研究与预报模型,在垂直空间针对海雾所在空间区域设置更为密集的η分层,对2015年4月28日~2015年4月29日的渤海海雾过程进行数值模拟分析,得到云水混合比、雾顶高度等海雾特征参数的数据,进而计算出影响激光回波的水平能见度数据。研究结果表明:对于海雾所在空间区域(海拔高度400 m以下),增大η分层数能够进一步细化海雾的特征参数,提高获取的数据精度;能见度参数可以通过云水混合比等海雾特征参数推算得到,其精度受海雾参数精度影响。 展开更多
关键词 激光引信 海雾 中尺度数值大气模式 天气研究与预报 云水混合比 能见度 数值模拟 特征参数
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二维黏弹介质五点八阶超紧致有限差分声波方程数值模拟 认领
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作者 周诚尧 汪勇 +1 位作者 桂志先 于晓东 《科学技术与工程》 北大核心 2020年第1期54-63,共10页
首次将五点八阶超紧致有限差分格式(CCD8)用于黏弹介质声波方程的数值模拟中,并对该格式进行了频散分析和精度分析,与普通紧致差分格式进行比较。随后,根据泰勒级数展开黏滞声波方程,建立了位移场时间二阶离散格式,将CCD8用于对位移场... 首次将五点八阶超紧致有限差分格式(CCD8)用于黏弹介质声波方程的数值模拟中,并对该格式进行了频散分析和精度分析,与普通紧致差分格式进行比较。随后,根据泰勒级数展开黏滞声波方程,建立了位移场时间二阶离散格式,将CCD8用于对位移场空间导数的求取,且对CCD8格式进行稳定性研究。最后将CCD8格式运用于均匀介质模型以及水平层状介质模型以及Marmousi模型的数值模拟和波场特征分析及对比中。研究结果表明:①CCD8与CD8相比,具有更小的截断误差、更高的模拟精度以及低数值频散的优点;②CCD8具有较高稳定性;③采用完全匹配层(perfectly matched layer,PML)对人工边界进行处理后对均匀介质、水平层状介质以及Marmousi模型进行黏滞声波方程的数值模拟,发现模拟效果不错,从而验证了CCD8的实用性和有效性性。 展开更多
关键词 五点八阶超紧致差分 黏弹介质声波方程 数值频散 稳定性条件 数值模拟
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基于iS3的复杂地质建模与数值数字一体化研究 认领
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作者 李培楠 石来 +1 位作者 刘俊 李晓军 《重庆交通大学学报:自然科学版》 CAS CSCD 北大核心 2020年第3期142-148,共7页
三维地质建模与数值模拟是地下空间开发重要的分析工具,然而目前地质建模的数据难以简便地应用于数值模拟中,不能准确表征地层的分布是造成数值模拟计算结果可靠性较低的主要原因之一。基于多源数据耦合建模理论,结合钻孔数据、地层接... 三维地质建模与数值模拟是地下空间开发重要的分析工具,然而目前地质建模的数据难以简便地应用于数值模拟中,不能准确表征地层的分布是造成数值模拟计算结果可靠性较低的主要原因之一。基于多源数据耦合建模理论,结合钻孔数据、地层接触约束及地层产状信息,通过借助潜势场方法的协克里金梯度插值法可建立复杂区域的地质模型。将地质模型接入iS3平台,纳入工程统一的信息化管理系统。并通过二次开发,将地质模型的数据与数值模拟相结合,在满足网格质量和模拟复杂的施工工况的要求下,充分考虑地层的空间分布。以南京地铁5号线为应用对象,结果表明:多源数据耦合建模可以较好地揭露盾构穿越段复合地层的空间分布形态,基于iS3平台,可进一步利用地质建模成果,在数值模拟中可以充分考虑地层的不均匀分布,实现数值数字一体化。 展开更多
关键词 地质工程 地质建模 数值模拟 数值数字一体化 iS3平台
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软弱夹层特性对露天矿边坡稳定性影响的应用研究 认领
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作者 杨宫印 崔鹏艳 陈玉明 《矿产与地质》 2020年第1期166-172,共7页
软弱夹层是岩体结构中存在的常见构造之一,明确其各类物理特性对边坡的作用机理,是确保边坡稳定性的首要任务。结合某石英石矿露天边坡实际工程,确定了软弱夹层倾角θ、黏聚力C、内摩擦角φ、厚度D四个物理参数,利用FLAC 3D数值分析软... 软弱夹层是岩体结构中存在的常见构造之一,明确其各类物理特性对边坡的作用机理,是确保边坡稳定性的首要任务。结合某石英石矿露天边坡实际工程,确定了软弱夹层倾角θ、黏聚力C、内摩擦角φ、厚度D四个物理参数,利用FLAC 3D数值分析软件进行数值模拟,系统分析了各物理参数变化对边坡稳定性的影响规律,为防止露天矿边坡失稳、设计治理方案提供可靠的理论依据。 展开更多
关键词 软弱夹层 边坡稳定性 数值模拟 FLAC 3D数值分析软件 影响规律
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采区带压开采底板破坏规律分析及防突涌研究 认领
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作者 冯宁 《山东煤炭科技》 2020年第1期151-153,156,159共5页
山西省长治经坊煤业有限公司八采区3-7081工作面受正断层影响,底板破断严重。采用相似模拟试验及数值模拟对工作面底板的不同点位的应力变化以及应力随时间的变化规律进行研究,得出距离煤柱20m处为底板受力薄弱的地方,受带压开采影响,... 山西省长治经坊煤业有限公司八采区3-7081工作面受正断层影响,底板破断严重。采用相似模拟试验及数值模拟对工作面底板的不同点位的应力变化以及应力随时间的变化规律进行研究,得出距离煤柱20m处为底板受力薄弱的地方,受带压开采影响,底板应力随时间处于动态变化,并提出了提前探放水措施、注浆加固等防突涌措施。 展开更多
关键词 带压开采 断层 相似模拟 数值模拟 应力 塑性变化
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基于Unity3D的某型叉车数值模拟 认领
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作者 张永亮 李向东 +1 位作者 郭锋 莫方伟 《科技视界》 2020年第5期87-89,共3页
根据某型叉车的机械结构组成和运动规律特点,利用Pro/E软件创建其三维零件模型,并组装成实体模型。运用Unity3D对某型叉车进行3D建模并仿真,利用软件中物理引擎,脚本模拟变速器和液压系统等技术,分别实现某型叉车碰撞和摩擦数值模拟,同... 根据某型叉车的机械结构组成和运动规律特点,利用Pro/E软件创建其三维零件模型,并组装成实体模型。运用Unity3D对某型叉车进行3D建模并仿真,利用软件中物理引擎,脚本模拟变速器和液压系统等技术,分别实现某型叉车碰撞和摩擦数值模拟,同时也实现了驾驶运动和作业运动的仿真,通过对比发现其仿真效果与实际运动相一致。 展开更多
关键词 虚拟现实 叉车 UNITY3D 运动仿真
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160mm×160mm小方坯连铸结晶器内流场数值模拟 认领
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作者 薛瑞 张燕超 +2 位作者 张彩军 王重君 刘志远 《中国冶金》 CAS 北大核心 2020年第1期51-57,共7页
采用Fluent软件对断面为160mm×160mm小方坯结晶器建立了三维稳态数学模型,以结晶器表面流速以及结晶器内钢液的流场状态为主要参考目标,模拟研究了160mm×160mm小方坯结晶器在不同拉速条件下相适应的水口浸入深度,并对数值模... 采用Fluent软件对断面为160mm×160mm小方坯结晶器建立了三维稳态数学模型,以结晶器表面流速以及结晶器内钢液的流场状态为主要参考目标,模拟研究了160mm×160mm小方坯结晶器在不同拉速条件下相适应的水口浸入深度,并对数值模拟结果相应地进行了水模拟验证。结果表明,当小方坯结晶器的拉速为1.7~1.9m/min、浸入深度为80~100mm时,结晶器内流场较为适宜,不会因液面波动剧烈而造成卷渣等问题。研究结果为小方坯连铸结晶器制定合理的浇注工艺提供了理论指导。 展开更多
关键词 小方坯 结晶器 流场 数值模拟 水模拟
扩隅凹模精密成形直齿圆柱内齿轮试验研究 认领
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作者 吴泽 张如华 +1 位作者 郭开元 曾广元 《塑性工程学报》 CAS CSCD 北大核心 2020年第3期43-50,共8页
为解决内齿轮塑性成形工艺中存在的角隅填充困难及成形力大等问题,在已有的扩腔凹模成形柱形齿轮的研究基础上进一步探索直齿圆柱内齿轮的扩隅凹模精密成形工艺。以模数为3 mm,齿数为18,外径为Φ80 mm的直齿圆柱内齿轮为研究对象,利用DE... 为解决内齿轮塑性成形工艺中存在的角隅填充困难及成形力大等问题,在已有的扩腔凹模成形柱形齿轮的研究基础上进一步探索直齿圆柱内齿轮的扩隅凹模精密成形工艺。以模数为3 mm,齿数为18,外径为Φ80 mm的直齿圆柱内齿轮为研究对象,利用DEFORM-3D有限元软件和设计制作的试验模具对新成形工艺进行了数值模拟和物理模拟试验研究,初步探讨了扩隅空间几何参数(扩隅斜角α、扩隅空间齿宽方向尺寸b和扩隅空间齿高方向尺寸h)对内齿轮成形效果的影响。研究表明,新工艺成形载荷较闭式模锻工艺可降低约70%;α或(b,h)值越大,镦压成形力越大,而顶出成形力越小,角隅填充更加饱满,当α或(b,h)值过大时,内齿轮下角隅产生废料,当α取8°~14°,b取(1/4~1/2)齿宽B,h取(1/4~1/2)齿高H时,可获得成形质量良好的内齿轮锻件。等效应力分布均匀,无应力集中,且在模具承受范围之内。物理模拟试验得到了齿形饱满、轮廓清晰且无折叠等缺陷的铅制齿轮,与数值模拟结果吻合良好。 展开更多
关键词 直齿内齿轮 精密成形 闭式模锻 数值模拟 物理模拟试验
厚层稠油油藏直平组合火驱优化 认领
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作者 赵睿智 陈明贵 +3 位作者 高飞 程海清 宋杨 喻高明 《断块油气田》 CAS CSCD 北大核心 2020年第2期233-237,共5页
文中根据辽河油田G3区块火驱试验区地质油藏特征、火驱实验数据,运用油藏工程、数值模拟及分析化学方法,建立了包含4相7组分火驱反应动力学方程,并拟合物理模拟结果及实际生产动态,确定方程配平系数、指前因子、活化能、焓变值等关键参... 文中根据辽河油田G3区块火驱试验区地质油藏特征、火驱实验数据,运用油藏工程、数值模拟及分析化学方法,建立了包含4相7组分火驱反应动力学方程,并拟合物理模拟结果及实际生产动态,确定方程配平系数、指前因子、活化能、焓变值等关键参数,建立了该区块火驱油层数值模型。同时,对影响直平组合火驱开发效果的水平井与直井的位置、水平井在油层内的纵向位置、水平段长度、注空气强度及水平井排液量等关键参数进行了优化设计。研究结果表明:该区域水平井部署在油层中部位置、水平段合理长度为280~300 m、合理注空气速度在1.0×10^4~1.5×10^4m^3/d、水平井采液速度为50~70 m^3/d时,水平井及其所在井组产量稳定,采出程度较高,开发效果较好。研究结果对该区域直平组合火驱方案设计及相似油田同类方案设计具有指导意义。 展开更多
关键词 物理模拟 反应动力学方程 数值模拟 直平组合
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深圳大运体育中心行人风环境的大涡模拟 认领
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作者 卢春玲 刘宇杰 李秋胜 《科学技术与工程》 北大核心 2020年第12期4810-4817,共8页
建筑群附近风环境的品质,直接影响地面行人的舒适与安全。以深圳大运体育中心主要建筑为工程对象,采用一种新的湍流脉动流场生成方法(discretizing and synthesizing random flow generation,DSRFG)模拟风场的实际湍流边界条件,基于数... 建筑群附近风环境的品质,直接影响地面行人的舒适与安全。以深圳大运体育中心主要建筑为工程对象,采用一种新的湍流脉动流场生成方法(discretizing and synthesizing random flow generation,DSRFG)模拟风场的实际湍流边界条件,基于数值模拟计算软件Fluent,对深圳大运会体育场馆为中心10 km范围内的山体和主要建筑物进行全尺寸大涡模拟计算,得到各风向角下体育中心速度场分布。结合当地气象资料,采用超越阈值概率法对体育场馆周围场地行人风环境进行预测与评估,并对风环境较差地区的成因进行分析并提供改良建议。结果表明:该研究方法可以较准确地预测出建筑群周围风环境分布,并为类似体育场馆设计的合理性以及行人风环境的研究与优化提供有价值的参考。 展开更多
关键词 数值模拟 深圳大运体育中心 大涡模拟 风流场 行人风环境
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