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对涡旋流影响压气机转子性能和稳定性的研究 被引量:4
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作者 屠宝锋 胡骏 张凯 《推进技术》 EI CAS CSCD 北大核心 2016年第4期640-645,共6页
为研究对涡旋流影响跨声速轴流压气机性能和稳定性的机理,设计了一种叶片式旋流发生器,并对旋流发生器和跨声速单转子进行了联合数值模拟研究。计算结果表明旋流发生器叶片数越少,对涡强度越低;对涡旋流导致压气机总压比、峰值效率、稳... 为研究对涡旋流影响跨声速轴流压气机性能和稳定性的机理,设计了一种叶片式旋流发生器,并对旋流发生器和跨声速单转子进行了联合数值模拟研究。计算结果表明旋流发生器叶片数越少,对涡强度越低;对涡旋流导致压气机总压比、峰值效率、稳定工作范围和堵塞边界流量减小,失速边界流量增大,对涡强度等于60°时峰值效率和堵塞边界流量分别降低1.11%和2.12%,失速边界流量增加4.17%;对涡中的同向涡导致叶尖进口攻角增加,进口相对马赫数减小;反向涡使叶尖进口攻角降低,进口相对马赫数增大;对涡前缘的轴向速度偏低,造成叶尖进口攻角大幅增加,叶尖泄漏流堵塞严重;由于叶尖泄漏流在叶片前缘溢流导致失稳。 展开更多
关键词 压气机 跨声速 对涡 效率 稳定性
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用四面体涡发生器研究进气道旋流畸变 被引量:3
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作者 符小刚 张晓飞 《机械制造》 2011年第12期28-30,共3页
对涡是航空发动机S型进气道中最常见的畸变形式。数值模拟了利用具有垂直前缘的四面体型涡发生器在风洞中产生的对涡旋流畸变,结果表明,此涡发生器可以在风洞中产生一对分布对称、彼此对转的涡流,并且在风洞中造成的流量损失极小,可以... 对涡是航空发动机S型进气道中最常见的畸变形式。数值模拟了利用具有垂直前缘的四面体型涡发生器在风洞中产生的对涡旋流畸变,结果表明,此涡发生器可以在风洞中产生一对分布对称、彼此对转的涡流,并且在风洞中造成的流量损失极小,可以忽略不计。与无对涡时的情况相比,风洞中越向后部对涡造成的总压损失越大。而在相同截面上当来流约为1.6 Ma时总压损失最大,在低亚音速以及较高超音速来流条件下的总压损失相对较小。 展开更多
关键词 进气道 旋流畸变 对涡 发生器
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对涡旋流对跨声速压气机转子Rotor67的影响
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作者 冯路宁 程邦勤 王加乐 《工程热物理学报》 EI CAS CSCD 北大核心 2021年第9期2284-2291,共8页
为研究对涡旋流畸变对压气机的影响,本文基于一种新设计的旋流畸变发生器,利用CFD技术,开展了对涡旋流畸变与NASA Rotor67跨声速转子的数值仿真研究。在100%换算转速下,对比分析均匀进气以及旋流进气条件下的压气机压比、效率特性线以... 为研究对涡旋流畸变对压气机的影响,本文基于一种新设计的旋流畸变发生器,利用CFD技术,开展了对涡旋流畸变与NASA Rotor67跨声速转子的数值仿真研究。在100%换算转速下,对比分析均匀进气以及旋流进气条件下的压气机压比、效率特性线以及流场分布情况。结果表明,对涡旋流会引起压气机增压能力和效率的下降,并降低压气机稳定工作裕度。在100%换算转速、旋流进气条件下压气机峰值效率点处的流量值较之均匀进气条件下降低2.33%,峰值效率降低2.44%,该点处压比降低0.25%。压气机失速点流量增加0.99%,压气机稳定工作流量范围下降。 展开更多
关键词 CFD 对涡 Rotor67 旋流畸变 压气机
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叶片式旋流畸变发生器数值模拟研究 被引量:10
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作者 屠宝锋 胡骏 尹超 《推进技术》 EI CAS CSCD 北大核心 2015年第12期1817-1824,共8页
为研究旋流畸变对压气机性能和稳定性的影响,设计了一套叶片式旋流畸变发生器,使用不同弯角的叶片以改变旋流畸变的结构和强度。采用CFD数值模拟方法对旋流畸变发生器的特性和详细流场进行了研究,结果表明,叶片式旋流畸变发生器具有对... 为研究旋流畸变对压气机性能和稳定性的影响,设计了一套叶片式旋流畸变发生器,使用不同弯角的叶片以改变旋流畸变的结构和强度。采用CFD数值模拟方法对旋流畸变发生器的特性和详细流场进行了研究,结果表明,叶片式旋流畸变发生器具有对涡和整体涡均可形成、总压恢复系数高、旋流强度调节方便的优点,旋流切向气流角最大可达25.1°;随着流量减小,对涡和整体涡的总压恢复系数增加,旋流强度先保持不变,在降至一定的流量值后急剧上升。在压气机进口截面,对涡强度近端壁区域最大,叶中区域最小。整体涡偏心时,压气机进口的旋流方向并不完全一致,在叶根局部区域会形成反向旋流。 展开更多
关键词 旋流畸变 叶片 整体 对涡 数值模拟
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腔室型旋流发生器的设计与仿真研究 被引量:5
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作者 纪振伟 程邦勤 +1 位作者 张磊 王浩 《推进技术》 EI CAS CSCD 北大核心 2018年第4期776-784,共9页
为了模拟旋流畸变对压气机性能和稳定性的影响,设计了一套腔室型旋流发生器,通过灵活改变腔室几何构形来形成不同类型和强度的旋流,利用先进的CFD数值模拟方法开展了旋流器流场特征的研究并对旋流畸变指标进行了详细分析。结果表明,腔... 为了模拟旋流畸变对压气机性能和稳定性的影响,设计了一套腔室型旋流发生器,通过灵活改变腔室几何构形来形成不同类型和强度的旋流,利用先进的CFD数值模拟方法开展了旋流器流场特征的研究并对旋流畸变指标进行了详细分析。结果表明,腔室型旋流发生器能够产生不同强度的整体涡和对涡旋流,气动交界面处整体涡最大旋流角可以达到65.8°,对涡最大旋流角可以达到58.2°;在压气机进口截面,近壁面处旋流强度最大,整体涡可达43.5,对涡可达9.26;整体涡主要影响叶尖流场,对涡主要影响叶尖和叶根的流场。随着流量的增加,旋流器总压恢复系数降低,整体涡强度增加,对涡强度降低。 展开更多
关键词 腔室 旋流畸变 旋流角 整体 对涡 数值仿真 试验技术
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一种平面埋入式进气道的地面工作特性及流态特征 被引量:7
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作者 孙姝 郭荣伟 伍贻兆 《航空动力学报》 EI CAS CSCD 北大核心 2007年第3期390-395,共6页
对一种平面埋入式进气道的地面工作特性进行了实验研究,结合数值仿真技术,分析了地面工作状态下该类进气道的流态特征,并探讨了其出口总压图谱的形成成因.结果表明:(1)虽然进气道出口截面的二次流较弱,但通道内却存在强的以对涡为特征... 对一种平面埋入式进气道的地面工作特性进行了实验研究,结合数值仿真技术,分析了地面工作状态下该类进气道的流态特征,并探讨了其出口总压图谱的形成成因.结果表明:(1)虽然进气道出口截面的二次流较弱,但通道内却存在强的以对涡为特征的旋流,该对涡因埋入式进气道进口侧棱的存在而产生,与后唇口前缘的气流分离共同导致了进气道出口截面的大面积低总压区;(2)地面工作状态下,埋入式进气道的总压恢复系数随出口马赫数的上升而下降,周向畸变指数、紊流度和综合畸变指数则随着出口马赫数的增加而增加.在相同的出口马赫数下,地面工作状态的总压恢复系数高于飞行状态,各种畸变指数也明显偏高.但当发动机的进口工作马赫数为0.35左右时,进气道出口截面的综合畸变指数W小于10.0%,满足常规发动机的稳定工作要求;(3)计算和实验结果对比表明,所得到的进气道出口总压恢复系数相对误差在1.2%以内,但畸变指数整体偏大. 展开更多
关键词 航空 航天推进系统 平面埋入式进气道 地面工作状态 对涡 总压恢复系数
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纳米流体Rayleigh-Bénard细胞流的格子-Boltzmann模拟 被引量:4
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作者 陆规 段远源 王晓东 《热科学与技术》 CAS CSCD 北大核心 2013年第1期1-7,共7页
采用热格子-Boltzmann方法,对两平行平板间纳米流体的Rayleigh-Bénard细胞流现象及其影响因素进行数值模拟研究,模型计算结果与方腔内纳米流体的自然对流实验结果吻合较好。讨论了纳米颗粒种类(Al2O3、Cu和SiO2)、体积分数(1%~4%... 采用热格子-Boltzmann方法,对两平行平板间纳米流体的Rayleigh-Bénard细胞流现象及其影响因素进行数值模拟研究,模型计算结果与方腔内纳米流体的自然对流实验结果吻合较好。讨论了纳米颗粒种类(Al2O3、Cu和SiO2)、体积分数(1%~4%)等因素对细胞流流动和传热的影响。研究发现平板间纳米流体的Rayleigh-Bénard细胞流的流动和传热行为明显异于纯流体,同时发现纳米流体的热导率、黏度和颗粒的热运动共同决定细胞流的流场和温度场分布的规律:热导率越大、布朗运动的越强,会减小流体温度的非均匀性,削弱对流作用,使其细胞流对涡个数减小;黏度增大也会抑制细胞流的发展。 展开更多
关键词 格子-Boltzmann模拟 Rayleigh-Bénard细胞流 对涡 纳米流体
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旋流畸变影响低速轴流压气机数值模拟研究 被引量:5
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作者 屠宝锋 胡骏 《推进技术》 EI CAS CSCD 北大核心 2016年第9期1649-1656,共8页
为研究进气旋流畸变对轴流压气机性能和稳定性影响的机理,设计了一种叶片式旋流畸变发生器,分别采用定常和非定常计算方法对旋流畸变发生器和两级低速轴流压气机进行了联合数值模拟研究。定常计算结果表明:旋流畸变发生器的叶片弯角越... 为研究进气旋流畸变对轴流压气机性能和稳定性影响的机理,设计了一种叶片式旋流畸变发生器,分别采用定常和非定常计算方法对旋流畸变发生器和两级低速轴流压气机进行了联合数值模拟研究。定常计算结果表明:旋流畸变发生器的叶片弯角越大、对涡强度越高;对涡旋流导致压气机总压比和效率降低,稳定边界流量明显增加;对涡强度越大,对压气机性能和稳定性影响越严重;对涡的反向涡对压气机影响较大,同向涡影响较小;反向涡造成部分叶片的叶根区域吸力面附面层提前分离,是导致压气机失稳的主因;非定常解的总压比和效率均略高于定常解,两种计算方法得到的稳定边界差异明显,非定常解的稳定边界流量比定常解小19.2%,非定常计算结果更接近试验值。 展开更多
关键词 压气机 旋流畸变发生器 对涡 附面层分离 稳定性
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旋流畸变对跨声速转子性能影响的数值研究
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作者 王加乐 程邦勤 +3 位作者 冯路宁 纪振伟 李军 马彩东 《推进技术》 EI CAS CSCD 北大核心 2021年第5期1013-1022,共10页
为了探究整体涡和对涡旋流对跨声速转子性能的影响,利用腔室型旋流畸变发生器产生旋流,并与跨声速转子进行联合仿真研究。结果表明:同向整体涡减小了叶片负荷与叶片表面及通道内的二次流分离,使转子的压比降低,效率升高;反向整体涡增大... 为了探究整体涡和对涡旋流对跨声速转子性能的影响,利用腔室型旋流畸变发生器产生旋流,并与跨声速转子进行联合仿真研究。结果表明:同向整体涡减小了叶片负荷与叶片表面及通道内的二次流分离,使转子的压比降低,效率升高;反向整体涡增大了叶片负荷,使流动分离损失增加,转子的压比升高,效率降低;对涡旋流可认为是同向整体涡和反向整体涡的叠加,对转子性能的影响取决于占主导的旋流类型,影响机制与整体涡相同。 展开更多
关键词 转子 旋流 畸变 整体 对涡 数值仿真 流动分离
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VIBRATION NUMERICAL ANALYSIS OF COUNTER-ROTATING TURBINE WITH WAKE-FLOW USING FLUID-STRUCTURE INTERACTION METHOD 被引量:3
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作者 赵振华 吕文亮 +1 位作者 陈伟 吴铁鹰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第1期66-72,共7页
The design of counter-rotating turbine is one of new techniques to improve the thrust-weight ratio of jet propulsion engines.Numerical analysis of a low pressure(LP)counter-rotating turbine rotor blade is presented ... The design of counter-rotating turbine is one of new techniques to improve the thrust-weight ratio of jet propulsion engines.Numerical analysis of a low pressure(LP)counter-rotating turbine rotor blade is presented by using ANSYS/CFX software.Interaction of aerodynamics and solid mechanics coupling in the computation is applied.In some rating of turbine,stress distribution and vibration characteristics of low pressure turbine(LPT)blade are computed.The wake aerodynamic forces and LPT blade vibration are transformed in frequency domain using fast Fourier transform(FFT)method.The results show that under wake aerodynamic force excitation,the first order modal vibration is more easily aroused and the higher order response cannot be ignored.Moreover,with different temperature fields,the vibration responses of blade are also different. 展开更多
关键词 counter-rotating turbine fluid and structure coupling vibration responses numerical analysis
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旋流畸变对压气机失速发展过程影响的试验研究 被引量:8
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作者 刘华 屠宝锋 +1 位作者 胡骏 谢金哲 《推进技术》 EI CAS CSCD 北大核心 2017年第10期2306-2313,共8页
为研究进气旋流畸变对轴流压气机失速发展过程的影响,设计了一种叶片式旋流畸变发生器。通过改变叶片式旋流畸变发生器的叶片安装方式来改变进口气流流向,产生对涡或整体涡,研究均匀进气、对涡和整体涡进气条件下低速轴流压气机失速发... 为研究进气旋流畸变对轴流压气机失速发展过程的影响,设计了一种叶片式旋流畸变发生器。通过改变叶片式旋流畸变发生器的叶片安装方式来改变进口气流流向,产生对涡或整体涡,研究均匀进气、对涡和整体涡进气条件下低速轴流压气机失速发展的特点。试验结果表明:旋流畸变发生器达到了预期的设计要求,在压气机进口前产生了对涡和整体涡。压气机转子对进口旋流畸变有很大的影响,对正向旋流有一定加强作用,使正向旋流强度增大;对反向旋流有一定抑制作用。旋流畸变减小了压气机的稳定裕度,切向气流角越大效果越明显,使其更快进入失速,其中以对涡进气和正向涡进气条件下最为明显。旋流畸变进气条件下压气机中失速团的产生机理不发生改变,失速团传播频率不发生改变。 展开更多
关键词 叶片式旋流畸变发生器 对涡 整体 失速起始
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进口边界层吸入对S弯进气道流场影响的数值研究
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作者 常心悦 闵浩 +2 位作者 田园 李康 王飞飞 《燃气涡轮试验与研究》 北大核心 2020年第6期22-27,60,共7页
采用三维数值模拟方法对S弯进气道流场特性进行了研究。通过对比S弯进气道有无进口边界层吸入的不同条件,分析了进口边界层吸入时进气道内部流场结构的变化。结果表明,无边界层吸入时,进气道流场均匀,底部无分离现象;有边界层吸入时,进... 采用三维数值模拟方法对S弯进气道流场特性进行了研究。通过对比S弯进气道有无进口边界层吸入的不同条件,分析了进口边界层吸入时进气道内部流场结构的变化。结果表明,无边界层吸入时,进气道流场均匀,底部无分离现象;有边界层吸入时,进气道进口出现了马蹄涡,底部存在较大的低压区,并在出口位置形成典型的对涡结构。进一步研究发现,改变进气道出口马赫数,将导致进气道进口流场结构、内部流场以及出口对涡结构变化。 展开更多
关键词 S弯进气道 边界层吸入 对涡 马蹄 流场结构 数值模拟
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The Impact of the Eastward Propagation of Convective Systems over the Tibetan Plateau on the Southwest Vortex Formation in Summer 被引量:9
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作者 FU Shen-Ming SUN Jian-Hua +1 位作者 ZHAO Si-Xiong LI Wan-Li 《Atmospheric and Oceanic Science Letters》 2010年第1期51-57,共7页
Based on the temperature of the black body (TBB),station observed and NCEP reanalysis data,the impacts of the eastward propagation of convective cloud systems over the Tibetan Plateau on the southwest vortex (SWV) for... Based on the temperature of the black body (TBB),station observed and NCEP reanalysis data,the impacts of the eastward propagation of convective cloud systems over the Tibetan Plateau on the southwest vortex (SWV) formation that occurred at 1800 UTC on 29 June 2003 are analyzed by using the Zwack-Okossi (Z-O) equation to diagnose the thermal and dynamic processes.It is found that,in summer,severe convective activities often occur over the Tibetan Plateau due to the abundant supply of moisture.The convective cloud near the east edge of the plateau could move eastward with a shortwave trough in the westerly.The divergent center that is induced by latent heat release,which is associated with severe convective activities,moves out with the convective cloud and contributes to the low level decompression which is favorable for the formation of plateau edge cyclogenesis (PEC).The Z-O equation indicates that,in this case,the latent heat release and convergence are the two most important factors for SWV formation,which amounts to about 42% and 15% of the term TOTAL,respectively.It is implied that the thermal process effect was more important than the dynamic process during SWV formation. 展开更多
关键词 Tibetan Plateau southwest vortex convective system temperature of the black body latent heat release plateau edge cyclogenesis
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Tropical Cyclone Tilts Under Vertically Varying Background Flows:Preliminary Results Based upon TCM4 Simulations 被引量:1
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作者 ZHENG Qikang LI Qingqing 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1066-1074,共9页
The characteristics of tropical cyclone(TC) tilts under vertically varying background flows were preliminarily examined in this study based on numerical simulations with the Tropical Cyclone Model version 4(TCM4).The ... The characteristics of tropical cyclone(TC) tilts under vertically varying background flows were preliminarily examined in this study based on numerical simulations with the Tropical Cyclone Model version 4(TCM4).The tilt magnitudes presented a linearly decreasing tendency in the simulation with the environmental wind speed vertically varying throughout the troposphere and in the simulation with the vertical wind shear concentrated in the lower troposphere,while the vortex tilt showed a linearly increasing tendency in magnitude in the simulation where the vertical shear was concentrated in the upper troposphere.The change in tilt magnitude was found to be related to the evolution of the penetration depth near the eyewall.When the shear was concentrated in the lower troposphere,the vortex tended to tilt downshear right during the early integration and underwent more precession processes.When the shear was concentrated in the upper troposphere,the vortex rapidly tilted downshear left during the early simulation and vortex precession was less frequently observed.The storms simulated in all experiments were finally in downshear-left tilt equilibrium. 展开更多
关键词 tropical cyclone TILT vertical wind shear penetration depth
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DIGNOSTIC ANALYSIS OF ASYMMETRIC SPIRAL RAINBANDS AROUND THE LANDING OF TYPHOON HAITANG (2005)
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作者 王勇 丁治英 +1 位作者 李勋 王群 《Journal of Tropical Meteorology》 SCIE 2010年第2期143-153,共11页
By using WRF mesoscale model, this paper carries out a numerical simulation and diagnostic analysis of the structural characteristics of the asymmetric spiral rain bands around the landing of Typhoon Haitang during th... By using WRF mesoscale model, this paper carries out a numerical simulation and diagnostic analysis of the structural characteristics of the asymmetric spiral rain bands around the landing of Typhoon Haitang during the period of July 19 to 20, 2005. The result indicated that the two rainbands associated with the precipitation centre was mainly located northeast of the typhoon centre. The movement and intensity of the southern rainband corresponded well with the 850-hPa positive vorticity band from 0200 to 1800 UTC July 19, 2005. Under the effect of cyclonic circulation, the positive vorticity band at 850 hPa connected with a southern rain band, leading to the intensification of rainfall in the southern centre of the precipitation. The southward rainband gradually moved toward and then merges with the northward one, strengthening the rainfall in the northern centre of the precipitation. Besides, the relationship between the heavy rainfall and the divergence field of vertical shear wind in the high altitude is analyzed. Finally, the relationship is revealed between the development of the vertical component of convective vorticity vector and the rainfall near the two centres of precipitation in the low altitude. 展开更多
关键词 diagnostic analysis asymmetrical spiral rain bands vertical shear wind convective vorticity vector
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Symmetry Analysis of Barotropic Potential Vorticity Equation
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作者 Alexander Bihlo RomanO.Popovych 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期697-700,共4页
Recently F. Huang [Commun. Theor. Phys. 42 (2004) 903] and X. Tang and P.K. Shukla [Commun. Theor. Phys. 49 (2008) 229] investigated symmetry properties of the barotropic potential vorticity equation without forci... Recently F. Huang [Commun. Theor. Phys. 42 (2004) 903] and X. Tang and P.K. Shukla [Commun. Theor. Phys. 49 (2008) 229] investigated symmetry properties of the barotropic potential vorticity equation without forcing and dissipation on the beta-plane. This equation is governed by two dimensionless parameters, F and β, representing the ratio of the characteristic length scale to the Rossby radius of deformation and the variation of earth' angular rotation, respectively. In the present paper it is shown that in the case F ≠ 0 there exists a well-defined point transformation to set β = 0. The classification of one- and two-dimensional Lie subalgebras of the Lie symmetry algebra of the potential vorticity equation is given for the parameter combination F ≠ 0 and β = 0. Based upon this classification, distinct classes of group-invariant solutions are obtained and extended to the case β ≠0. 展开更多
关键词 potential vorticity equation Lie symmetries classification of subalgebras exact solutions
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Fermionic Zero Modes in Self-dual Vortex Background on a Torus
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作者 LIU Yu-Xiao WANG Yong-Qiang DUAN Yi-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4X期675-679,共5页
We study fermionic zero modes in the self-dual vortex background on an extra two-dimensional Riemann surface in (5+1) dimensions. Using the generalized Abelian-Higgs model, we obtain the inner topological structure... We study fermionic zero modes in the self-dual vortex background on an extra two-dimensional Riemann surface in (5+1) dimensions. Using the generalized Abelian-Higgs model, we obtain the inner topological structure of the self-dual vortex and establish the exact self-duality equation with topological term. Then we analyze the Dirac operator on an extra torus and the effective Lagrangian of four-dimensional fermions with the self-dual vortex background. Solving the Dirac equation, the fermionic zero modes on a torus with the self-dual vortex background in two simple cases are obtained. 展开更多
关键词 fermionic zero modes large extra dimensions self-dual vortex
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Topological Aspects of Superconductors at Dual Point
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作者 REN Ji-Rong XU Dong-Hui ZHANG Xin-Hui DUAN Yi-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1627-1630,共4页
We study the properties of the Ginzburg-Landau model at the dual point for the superconductors. By making use of the U(1) gauge potential decomposition and the φ-mapping theory, we investigate the topological inner... We study the properties of the Ginzburg-Landau model at the dual point for the superconductors. By making use of the U(1) gauge potential decomposition and the φ-mapping theory, we investigate the topological inner structure of the Bogomol'nyi equations and deduce a modified decoupled Bogomol'nyi equation with a nontrivial topological term, which is ignored in conventional model. We find that the nontrivial topological term is closely related to the N-vortex, which arises from the zero points of the complex scalar field, Furthermore, we establish a relationship between Ginzburg Landau free energy and the winding number. 展开更多
关键词 dual point Bogomol'nyi equations VORTEX
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Effect of condensation latent heat release on the relative vorticity tendency in extratropical cyclones:a case study 被引量:1
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作者 SHEN Yang SUN Yana LIU Duanyang 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第4期275-285,共11页
Taking an extratropical cyclone that produced extreme precipitation as the research object,this paper calculates the contribution of condensation latent heat release(LHR)to relative vorticity tendency based on the com... Taking an extratropical cyclone that produced extreme precipitation as the research object,this paper calculates the contribution of condensation latent heat release(LHR)to relative vorticity tendency based on the complete-form vertical vorticity tendency equation.The results show that the heating rate of convectional condensation LHR can reach up to about 40 times that of stable condensation LHR.Both the stable and convectional heating centers are higher than 700 hPa,which would cause∂Q/∂z>0 and a positive vorticity source in the lower troposphere.The vertical gradient of stable condensation LHR contributes little to the growth of relative vorticity,while the relative vorticity tendency associated with the vertical gradient of convectional condensation LHR can be an order of magnitude higher than the former.The positive vorticity source is always located right below the latent heating center,and its maximum value can always be found in the lower troposphere.Convectional LHR is the primary factor for cyclone development from the perspective of diabatic heating.The horizontal gradient of total condensation LHR can contribute about 65%of the actual vorticity growth,but the effect of the vertical gradient of convectional condensation(LHR)can reach twice as much.The adiabatic heating from LHR can cause vorticity tendency directly.However,it can also change the vertical and horizontal gradient of potential temperature,which can further induce vorticity tendency. 展开更多
关键词 Complete-form vertical vorticity tendency equation stable condensation latent heat convectional condensation latent heat vorticity tendency
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Numerical simulation on conjugate heat transfer of turbine cascade
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作者 周驰 颜培刚 +1 位作者 姜澎 冯国泰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第6期741-745,共5页
Numerical simulation on conjugate heat transfer of an internal cooled turbine vane was carried out. Numerical techniques employed included the third-order accuracy TVD scheme, multi-block structured grids and the tech... Numerical simulation on conjugate heat transfer of an internal cooled turbine vane was carried out. Numerical techniques employed included the third-order accuracy TVD scheme, multi-block structured grids and the technique of arbitrary curved mesh. Comparison between results of commercial CFD codes with several turbulence models and those of this code shows that it is incorrect of commercial CFD codes to predict the thermal boundary layer with traditional turbulence models, and that turbulence models considering transition lead to more accurate heat transfer in thermal boundary layer with some reliability and deficiency yet. The results of this code are close to those of CFX with transition model. 展开更多
关键词 TURBINE conjugate heat transfer heat conduction numerical validation
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