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油水两相螺旋流状态下射频法测量原油含水率的方法 认领
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作者 张振远 张兴凯 +2 位作者 王文雄 古永红 廖锐全 《石油与天然气化工》 CAS 北大核心 2021年第1期101-107,118,共8页
目前,国内大多数油田进入采油后期,原油含水率显著提高,对含水率的测量提出了新的挑战。针对原油含水率的实时测量问题,提出了一种油水两相螺旋流状态下射频法测量含水率的新方法。首先将油水两相来流通过旋流器调整成螺旋流状态,然后... 目前,国内大多数油田进入采油后期,原油含水率显著提高,对含水率的测量提出了新的挑战。针对原油含水率的实时测量问题,提出了一种油水两相螺旋流状态下射频法测量含水率的新方法。首先将油水两相来流通过旋流器调整成螺旋流状态,然后测量螺旋流状态下管内同心布置的天线发射的射频信号,最后通过建立含水率与射频信号之间的关系模型及两相流速度滑移模型对测量结果进行修正,得到含水率的测量结果。该方法能够消除油水两相流型分布不均匀对测量结果的影响,扩宽了含水率的测量范围。通过室内实验的方法对测量模型进行了静态标定、动态验证和优化调整。实验结果表明,在入口油水两相混合流速为0.60~1.20 m/s,体积含水率高于43.81%时,利用该方法测量含水率误差在6.29%以内。 展开更多
关键词 原油含水率 射频法 螺旋流
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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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Concept of a swirling diffuser in batch blending tanks 认领
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作者 Wojciech Artichowicz Jerzy M.Sawicki 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2020年第2期378-382,共5页
The mixing of two or more components belongs to the category of the most common unit operations, both in technology and in nature. One particular version is homogenization(blending), the effectivity of which is strong... The mixing of two or more components belongs to the category of the most common unit operations, both in technology and in nature. One particular version is homogenization(blending), the effectivity of which is strongly related to the blending time. Among many differentiated individual solutions of mixing systems used in blenders, one should distinguish the class of agitators with diffusers. An analysis of the character of the velocity field during a blending chamber operation leads to the conclusion that it would be of avail to outfit a straight diffuser with different setups of elbows. In consequence, the vertical direction of the inflowing fluid stream would be changed into the horizontal direction of the outflowing stream, which should intensify the blending process. The concept has been verified experimentally, making use of the tracer methodology. The obtained results confirmed the theoretical conclusion that the blending time for the swirling-diffuser was shorter than for the classical straight one. 展开更多
关键词 BATCH BLENDING CHAMBER Swirling DIFFUSER BLENDING TIME
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Experimental and numerical study of the adsorption performance of a vortex suction device using water-swirling flow 认领
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作者 ZHU YaWei ZHOU RenGuan +2 位作者 YANG Gang ZHU YanQing HU DeAn 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2020年第6期931-942,共12页
An electrically activated underwater suction device is designed to form an amazing amount of negative pressure by generating water swirling flow,which can make underwater wall-climbing robot stick to the wall surface ... An electrically activated underwater suction device is designed to form an amazing amount of negative pressure by generating water swirling flow,which can make underwater wall-climbing robot stick to the wall surface allowing a ground clearance.For the purpose of a full understanding of the mechanism of the suction device,a series of experimental tests are carried out and a computational fluid dynamics(CFD)model is established.The results show that the suction force F is consistent between experimental tests and simulations.An insight into the flow phenomena of vortex suction device,including spatial velocity and pressure distribution,is given through numerical simulation analysis.Furthermore,the crucial parameters,i.e.,the rotation speedωand gap clearance h,are studied.Then the relationships of F-ωand F-h are clarified.It reveals that with the increasing of rotation speed,the suction force increases quadratically.And with the increasing of gap clearance,the suction force increases firstly and then decreases,so that a reasonable design interval of gap clearance can be got to obtain the required suction force for the engineering applications. 展开更多
关键词 vortex suction device hydrodynamic analysis swirling flow underwater wall-climbing robot CFD
存在温度扰动的圆环旋转黏性液体射流稳定性 认领
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作者 阎凯 宁智 +2 位作者 赵晋 吕明 孙春华 《高校化学工程学报》 EI CAS CSCD 北大核心 2020年第1期86-95,共10页
建立了同时存在速度扰动、压力扰动以及温度扰动的圆环旋转黏性液体射流稳定性色散方程。在此基础上,进行了存在温度扰动的圆环旋转黏性液体射流稳定性研究;通过气液温差分析了温度扰动强度对射流稳定性的作用,以贝克来数Pe为特征参数,... 建立了同时存在速度扰动、压力扰动以及温度扰动的圆环旋转黏性液体射流稳定性色散方程。在此基础上,进行了存在温度扰动的圆环旋转黏性液体射流稳定性研究;通过气液温差分析了温度扰动强度对射流稳定性的作用,以贝克来数Pe为特征参数,分析研究了射流液体热量传递特性与温度扰动对射流稳定性作用的影响。研究结果表明,温度扰动的存在使得圆环旋转黏性液体射流最大扰动增长率、最不稳定频率和不稳定截断频率增大,并使射流扰动增长率随扰动频率的变化规律发生变化;温度扰动有利于提高一定扰动频率下射流的轴对称扰动稳定性,使射流扰动占优模式发生变化。圆环旋转黏性液体射流最大扰动增长率、最不稳定频率和不稳定截断频率随气液温差和贝克来数Pe增加而增大;气液温差不会改变射流扰动占优模式;轴对称扰动射流的最大扰动增长率大于非轴对称扰动射流,其差值随气液温差和贝克来数Pe增加而增大。 展开更多
关键词 圆环 旋转 黏性液体 射流稳定性 温度扰动
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旋流驻涡燃烧室冷态流动特性数值分析 认领 被引量:1
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作者 要晋龙 徐青 +1 位作者 鄢平华 孙海俊 《弹箭与制导学报》 北大核心 2020年第2期51-54,59,共5页
为探究凹腔结构参数和进口旋流数对微型冲压发动机内流场的影响,采用数值计算方法对一种新型的旋流驻涡燃烧室模型进行了研究。结果表明:当凹腔结构参数L/D=0.72,H/D=0.5时,后体阻力系数小,燃烧室总压恢复系数高,在凹腔内形成光滑稳定... 为探究凹腔结构参数和进口旋流数对微型冲压发动机内流场的影响,采用数值计算方法对一种新型的旋流驻涡燃烧室模型进行了研究。结果表明:当凹腔结构参数L/D=0.72,H/D=0.5时,后体阻力系数小,燃烧室总压恢复系数高,在凹腔内形成光滑稳定的单涡结构;当旋流数增加,凹腔后的回流区被拉长,且延伸到燃烧室出口;低旋流数能提高燃烧室湍流强度及主流与回流区之间的传质;当旋流数S=0.1时,燃烧室总压恢复系数最高,在凹腔内也形成光滑单涡结构。 展开更多
关键词 驻涡燃烧室 旋流 凹腔 数值计算
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The Swirling Jet Generation Method and Its Effect on the Velocity Distribution 认领
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作者 Fernández Roque Tiburcio Correa Arredondo JoséArturo +3 位作者 Mejía Carmona Alejandro Sandoval Lezama Jorge Vázquez Flores JoséFélix Tiburcio Fernández Roque 《机械工程与自动化:英文版》 2020年第1期16-26,共11页
The wing tip vortex has a great similarity with the swirling jets.Since these are generated of a simpler and more economic form in a laboratory,it is relevant to determine which the best method is for the generation o... The wing tip vortex has a great similarity with the swirling jets.Since these are generated of a simpler and more economic form in a laboratory,it is relevant to determine which the best method is for the generation of the swirling jet.In this paper,the velocity distribution obtained experimentally with the method of generation here proposed,which consists of the employment of an axial fan without stators,is compared with the velocity distribution of swirling jets generated with three different methods.It is observed that the velocity distribution obtained with the proposed method is similar with one of the methods found in the references,which uses fixed blades guides at the entry of the pipe.The proposed method is suitable for the generation of the swirling jet and it is considered that it is simpler and more economic to use blades fixed guides. 展开更多
关键词 Swirling JET VELOCITY DISTRIBUTION SWIRL INTENSITY wingtip VORTEX tangential VELOCITY
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Analysis and correlation of fluid acceleration with vorticity and Liutex(Rortex)in swirling jets 认领 被引量:1
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作者 Nan Gui Hou-bo Qi +5 位作者 Liang Ge Peng-Xin Cheng Hao Wu Xing-tuan Yang Ji-yuan Tu Sheng-yao Jiang 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第5期864-872,共9页
The characteristics of the acceleration a and its correlation with the vortex core in the swirling flow are analyzed in this paper.The swirling flows of four swirl numbers(Sn=n S 0,0.10,0.20 and 0.36)are simulated by ... The characteristics of the acceleration a and its correlation with the vortex core in the swirling flow are analyzed in this paper.The swirling flows of four swirl numbers(Sn=n S 0,0.10,0.20 and 0.36)are simulated by the direct numerical simulation,and the fluid mass particles from the inlet of the swirling flow are traced as a database for the current study.The correlations of the acceleration a with the vortex identification parameters of R andωare quantified,where R is the parameter of the“Liutex”-method proposed by Prof.Liu,and its early version is“Rortex”.The probability density functions of the included angles of a-R and a-ωare computed,which are used to clarify the geometrical configuration between a and R.The covariance coefficients between a and the parameters of various vortex core criteria(Q,λ2,ΩL,ΩR,ωand R)are computed and their relative levels of correlation are compared.Compared to the velocity,the expectation and the rms of the acceleration magnitudes and its projections on R and the plane perpendicular to R are computed for better explaining the correlation features between a and R.It is found that a and R are always either perpendicular or parallel to each other with the quantized included angles of∠(a,R)=kπ/2,(k=0,1,2).This confirms the role of R which works as the axis of the vortex exclusively. 展开更多
关键词 swirling flow ACCELERATION correlation VORTEX Rortex Liutex direct NUMERICAL simulation
Hydrodynamics and solids mixing in fluidized beds with inclined-hole distributors 认领
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作者 Alhussain Bakhurji Xiaotao Bi John R. Grace 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第2期19-28,共10页
Experimental fluidization results were compared for three gas distributors with the same opening ratio but different orifice in clinations (30,45 , and 90 ). Hydrodynamic studies were con ducted with glass beads (diam... Experimental fluidization results were compared for three gas distributors with the same opening ratio but different orifice in clinations (30,45 , and 90 ). Hydrodynamic studies were con ducted with glass beads (diameter 154p.m) to evaluate the impacts of orifice inclination and static bed depth on pressure drop, pressure drop fluctuations, bed expansion, and minimum fluidization velocity. Solids residence time distributions were determined using phosphoresce nt tracer particles (mea n diameter 76 pm), activated by ultraviolet light. The bed pressure drop was higher with the inclined-hole distributors and increased with static bed height. In a shallow bed, the inclined-hole distributors gave less expansion;however, in deep beds, the orifice angle had negligible influence on bed expansion. The minimum fluidization velocity varied with static bed height for the inclined-hole distributors and was higher for steeper angles. The turnover time estimated using bubbling-bed equations matched the experimental results well for vertical mixing. Probes and ports at the walls of the fluidization column reduced the dense-phase downward velocity by up to 40%. The tangential particle velocity was highest for the 30 -hole distributor and decreased with increasing orifice angle. Tangential mixing was described by a dispersion model;the dispersion coefficient for the inclined-hole distributors was approximately twice that for the 90 -hole distributor in a shallow bed. 展开更多
关键词 Swirling fluidized bed FLUIDIZATION SOLIDS MIXING Inclined-hole DISTRIBUTOR
Experimental investigation on flow characteristics in circular tube inserted with rotor-assembled strand using PIV 认领 被引量:2
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作者 Lichen He Weimin Yang +3 位作者 Changfeng Guan Hua Yan Lin Zheng Xiahua Zuo 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期1-9,共9页
Rotor-assembled strand works as a typical tube insert to achieve heat transfer augmentation and scale inhibition in a heat exchanger.In this work, the PIV experiment regarding the flow fields in a circular tube insert... Rotor-assembled strand works as a typical tube insert to achieve heat transfer augmentation and scale inhibition in a heat exchanger.In this work, the PIV experiment regarding the flow fields in a circular tube inserted with rotor-assembled strand was conducted and the flow characteristics on transverse section and longitudinal section were analyzed.The results showed that swirling flow was produced in the tube inserted with rotors and it was particularly strong within the swing diameter of the rotor on the section that contains the rotor;the average turbulence intensity and the radial velocity were improved notably;the velocity vectors on the longitudinal section remained along the direction of a straight line;both the swirling flow and average turbulence intensity were higher for the rotor with three blades than for the rotor with two blades except that the radial velocity was approximate, but they were all reduced by enlarging the lead of the rotor.Characterization of the flow patterns in a circular tube contributes to understanding the heat transfer efficiency and scale inhibition performance of the rotor-assembled strand and provides guidance for its application. 展开更多
关键词 Particle image VELOCIMETRY (PIV) Swirling flow Rotor-assembled STRAND Circular tube
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Structural Optimization of Electromagnetic Swirling Flow in Nozzle of Slab Continuous Casting 认领
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作者 Xiao-Wei Zhu De-Wei Li +2 位作者 Chun-Lei Wu Katsukiyo Marukawa Qiang Wang 《金属学报:英文版》 SCIE EI CAS CSCD 2018年第12期1317-1326,共10页
关键词 Continuous CASTING SUBMERGED ENTRY NOZZLE ELECTROMAGNETIC swirling flow SLAB Numerical simulation
Inlet flow disturbance effects on direct numerical simulation of incompressible round jet at Reynolds number 2500 认领
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作者 Zejing Hu Yongliang Zhang Zuojin Zhu 《力学快报:英文版》 CAS CSCD 2018年第5期345-350,363共7页
This letter reports inlet flow disturbance effects on direct numerical simulation of incompressible round jet at Reynolds number 2500.The simulation employs an accurate projection method in which a sixth order biased ... This letter reports inlet flow disturbance effects on direct numerical simulation of incompressible round jet at Reynolds number 2500.The simulation employs an accurate projection method in which a sixth order biased upwind difference scheme is used for spatial discretization of nonlinear convective terms,with a fourth order central difference scheme used in the discretization of the divergence of intermediate velocity.Carefully identifying reveals that the inlet flow disturbance has some influences on the distribution pattern of mean factor of swirling strength intermittency.With the increase of inlet disturbance magnitude jet core cone slightly shortens,observable differences occur in the centerline velocity and its fluctuations,despite the negligible impacts on the least square fitted centerline velocity decay constant(Bu)and distribution parameter(Ku)for velocity profile in self-similar region. 展开更多
关键词 INCOMPRESSIBLE round JET JET core CONE Biased UPWIND finite difference Swirling strength intermittency factor Accurate projection method
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原型水泵水轮机在泵工况驼峰特性研究 认领 被引量:1
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作者 王驰航 郭志伟 《中国农村水利水电》 北大核心 2018年第7期178-183,共6页
为了研究水泵水轮机驼峰区的流态变化,在活动导叶为15°开度下,采用SST k-ω模型对原型水泵水轮机在泵工况下的三维定常湍流进行数值模拟。结合实验数据,分析了驼峰区内不同流道位置随着流量的减小,水泵水轮机流场的变化规律。结果... 为了研究水泵水轮机驼峰区的流态变化,在活动导叶为15°开度下,采用SST k-ω模型对原型水泵水轮机在泵工况下的三维定常湍流进行数值模拟。结合实验数据,分析了驼峰区内不同流道位置随着流量的减小,水泵水轮机流场的变化规律。结果表明,机组在驼峰区运行时,隔舌附近活动导叶压力面与固定导叶吸力面之间的流道会有漩涡生成,随着流量的减小,涡的运动区域不断向整个双列叶栅流道扩散,当进入小流量低负荷区时,漩涡主要集中在叶轮出口和活动导叶进口的流道。通过对旋度场的观察与分析,发现在驼峰极小值工况处,强旋度区主要集中在整个双列叶栅,在小流量低负荷区,强旋度区主要集中在叶轮出口和活动导叶进口。 展开更多
关键词 水泵水轮机 水泵工况 数值模拟 驼峰特性 旋度
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Experimental Investigation of Two-Dimensional Velocity on the 90&deg;Double Bend Pipe Flow Using Ultrasound Technique 认领
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作者 San Shwin Ari Hamdani +1 位作者 Hideharu Takahashi Hiroshige Kikura 《力学国际期刊(英文)》 2017年第12期340-359,共20页
An experimental investigation was performed to investigate two-dimensional axial velocity field at downstream of the 90&deg;double bend pipe with and without inlet swirling condition. The main objectives are to fi... An experimental investigation was performed to investigate two-dimensional axial velocity field at downstream of the 90&deg;double bend pipe with and without inlet swirling condition. The main objectives are to find separation region and observe the influence of inlet swirling flow on the velocity fluctuation using ultrasound technique. The experiments were carried out in the pipe at Reynolds number Re = 1 × 104. In case of inlet swirling flow condition, a rotary swirler was used as swirling generator, and the swirl number was setup S = 1. The ultrasonic measurements were taken at four downstream locations of the second bend pipe. Phased Array Ultrasonic Velocity Profiler (Phased Array UVP) technique was applied to obtain the two-dimensional velocity of the fluid and the axial and tangential velocity fluctuation. It was found that the secondary reverse flow became smaller at the downstream from the bend when the inlet condition on the first bend was swirling flow. In addition, inlet swirling condition influenced mainly on the tangential velocity fluctuation, and its maximum turbulence intensity was 40%. 展开更多
关键词 Phased Array Ultrasonic VELOCITY PROFILER Swirling Flow TWO-DIMENSIONAL VELOCITY ROTARY SWIRLER
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Turbulence Modelling of a Single-Phase Flow Cyclone Gasifier 认领
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作者 Pantea Hadi Jafari J. Gunnar I. Hellstr?m B. Rikard Gebart 《工程(英文)(1947-3931)》 2017年第9期779-799,共21页
The current work aims to make a foundation for an engineering design of a cyclone gasifier to be able not only to predict its flow field with a suitable accuracy but also to investigate a large number of design altern... The current work aims to make a foundation for an engineering design of a cyclone gasifier to be able not only to predict its flow field with a suitable accuracy but also to investigate a large number of design alternatives with limited computer resources. A good single-phase flow model that can form the basis in an Euler-Lagrange model for multi-phase flow is also necessary?for modelling the reacting flow inside a cyclone gasifier. The present paper provides an objective comparison between several popular turbulence modelling options including standard k-ε and SST with curvature corrections, SSG-RSM and LES Smagorinsky models, for the single-phase flow inside cyclone separators/gasifiers that can serve as a guide for further work on the reacting multi-phase flow inside cyclone gasifiers and similar devices. A detailed comparison between the models and experimental data for the mean velocity and fluctuating parts of the velocity profiles are presented. Furthermore, the capabilities of the turbulence models to capture the physical phenomena present in a cyclone gasifier that?affects the design process are investigated. 展开更多
关键词 CYCLONE GASIFIER TURBULENCE MODELLING Swirling FLOW Pattern SECONDARY FLOW
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旋流冲击孔偏置方向对小尺寸涡轮叶片前缘冷却效果影响的数值研究 认领
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作者 王纯 张勃 +1 位作者 吉洪湖 赵旭阳 《重庆理工大学学报:自然科学版》 2016年第11期49-55,120共8页
根据小尺寸涡轮叶片的前缘特征,设计了U型通道冷却结构,在通道前缘设计了3种不同偏置方向的旋流冲击孔,改变了旋流方向,数值模拟研究了其对叶片前缘冷却效果的影响。结果表明:采用旋流冲击冷却结构时,冷却气附壁性增强,叶片前缘冷却效... 根据小尺寸涡轮叶片的前缘特征,设计了U型通道冷却结构,在通道前缘设计了3种不同偏置方向的旋流冲击孔,改变了旋流方向,数值模拟研究了其对叶片前缘冷却效果的影响。结果表明:采用旋流冲击冷却结构时,冷却气附壁性增强,叶片前缘冷却效果相比常规冲击冷却明显提高;采用冲击孔向偏吸力面设置,利用了吸力面的低压特点,冲击流速提高,使压力面与吸力面冷却效果均有增强;获得了燃气与冷却气沿程压力与温度变化,为冷却气流路优化设计与流量分配提供了基础。 展开更多
关键词 小尺寸涡轮叶片 叶片前缘 旋流冲击 偏置方向 流量分配
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Analysis of swirling flow effects on the characteristics of unsteady hot-streak migration 认领
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作者 Wang Jingyu Ge Ning Sheng Chunhua 《中国航空学报:英文版》 SCIE EI CAS CSCD 2016年第6期1469-1476,共8页
The temperature of flow at the combustor exit is inherently non-uniform and the hot fluid is called hot-streak. An in-house CFD software, NUAA-Turbo, was used to carry out 3D unsteady simulations on the PW-E~3 single-... The temperature of flow at the combustor exit is inherently non-uniform and the hot fluid is called hot-streak. An in-house CFD software, NUAA-Turbo, was used to carry out 3D unsteady simulations on the PW-E~3 single-stage high-pressure turbine. The hot-streak effect based on real stator and combustor counts was approximately evaluated by the contraction/dilatation method on the interface. The unsteady attenuation and migration process of hot-streaks in the turbine passage were well captured. The general performance parameters for different circumferential positions of hot-streaks were relatively consistent. Then, the influences of hot-streaks on blade surface temperature were investigated by comparing results under hot-streak and uniform inflow conditions. Unsteady simulations with combined inlet hot-streak and swirling flow show that the core of a hot-streak migrates to the tip under the influence of a positive swirl, while the phenomenon is just opposite with a negative swirl. Therefore, the heat transfer environment of rotor blades shows great differences with different directions of inlet swirl. 展开更多
关键词 High pressure turbine Hot-streak Interface contraction/dilatation Swirling FLOW UNSTEADY FLOW
Computational Analysis of Gas Phase Mixing in a Co-Fired Burner with Two Different Designs 认领
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作者 J. Iqbal S. Gao 《电力能源(英文)》 2015年第4期178-184,共7页
The study of swirling jet combustor for biomass coal co-firing is of great interest for energy industry. The biomass co-firing can serve as a NOx reduction method as well as the better use of renewable energy source. ... The study of swirling jet combustor for biomass coal co-firing is of great interest for energy industry. The biomass co-firing can serve as a NOx reduction method as well as the better use of renewable energy source. Large eddy simulation (LES) and RANS modelling have been performed with two different burner designs. Usually pulverized coal-biomass mixture enters the furnace along with primary air through primary pipe, and the secondary pipe provides necessary air and mixing for combustion. The improved model has three passages including primary, secondary and middle passage for swirling. The simulations on two geometries have been compared, and the aim is to design a better and improved burner model for better pre-combustion mixing in the biomass co- fired furnace. The results from two-way and three-way geometry have been compared with each other as well as with the results from the furnace model used by Apte and Mahesh [8]. 展开更多
关键词 Swirling Jet CO-FIRING Biomass TURBULENCE LES
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Progress in Physics of the Cosmos 认领
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作者 M. Zafar Iqbal 《天文学与天体物理学国际期刊(英文)》 2015年第2期79-89,共11页
Study of the Cosmos, at best, is considered a semi-scientific discipline, primarily because the la-boratory for carrying out measurements and tests of theories (the Cosmos) has been largely inac-cessible for centuries... Study of the Cosmos, at best, is considered a semi-scientific discipline, primarily because the la-boratory for carrying out measurements and tests of theories (the Cosmos) has been largely inac-cessible for centuries. The cosmic vista into the yonder, however, continued to fascinate humankind due to its inherent beauty and sheer curiosity. The invention of the optical telescope more than five centuries back, however, led to the opening of observational cosmology as a scientific discipline with firm experimental basis. However, the investigations based on visible light posed obvious limitations for the range of such observational cosmology. The advent of the radio telescope in the first half of the 20th century marked a fundamental new step in the progress of this branch of science. There has been no looking back in the march of knowledge in the discipline since then. A whole new vista was laid bare as a result of this development, leading to the discovery of altogether new celestial objects, such as quasars and pulsars and still newer galaxies. The parallel progress of the physics of fundamental constituents of the material world and their interactions led to an interesting merger of these two branches of physical sciences, yielding absolutely astounding knowledge of the nature and evolution of the Universe. New concepts of dark energy and dark matter thought to constitute the dominant share of the Universe were brought to light as a result of these new observations and theoretical ideas. This brief article aims to provide an overview of these exciting developments in the field of cosmology and the associated physics. 展开更多
关键词 Radio ASTRONOMY COSMIC Microwave Background DARK Energy DARK Matter Swirling B MODES
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LES investigation of swirl intensity effect on unconfined turbulent swirling premixed flame 认领 被引量:2
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作者 Zhihua Wang Yanwei Xu +3 位作者 Yu L Zhijun Zhou Junhu Zhou Kefa Cen 《中国科学通报:英文版》 SCIE CAS 2014年第33期4550-4558,共9页
一个有限反应率模型表现为大旋涡模拟(LES ) 的闭合数字地学习打漩的一口开的 premixed 甲烷 / 空气火焰。结果的模型被与报导数据作比较第一验证然后采用了调查打漩的效果流动地,火焰特征和打漩的火焰的燃烧不稳定性上的紧张。三不同... 一个有限反应率模型表现为大旋涡模拟(LES ) 的闭合数字地学习打漩的一口开的 premixed 甲烷 / 空气火焰。结果的模型被与报导数据作比较第一验证然后采用了调查打漩的效果流动地,火焰特征和打漩的火焰的燃烧不稳定性上的紧张。三不同打漩数字被考虑。LES 结果证明作为打漩,紧张增加,旋涡乘火车并且微混合被提高,在火焰前面导致更多的瘦相等的比率;因而,更高的打漩数字原因降低火焰温度和更慢的公司氧化;因为模仿的所有打漩数字,火焰前面完全从再通行地区被定位并且在环形的打漩蒸气的内部表面抛锚了;打漩数字在打漩上有关键效果向光线、正切的尺寸然后显著地的火焰扩展影响 streamwise 火焰长度,它是燃烧不稳定性上的一个大影响因素;在 streamwise 的火焰上的导致旋涡的骚乱在燃烧不稳定性起一个关键作用。 展开更多
关键词 预混火焰 旋流强度 LES 漩涡 燃烧不稳定性 潜水 大涡模拟 速率模型
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