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低扬程泵装置水力损失及水力设计流程分析

南水北调与水利科技 2008年第6期6卷 112-114页

作者：成立刘超 b. p. m. van esch 车晓红扬州大学江苏省水利动力工程重点实验室江苏扬州225009 Eindhoven University of Technology Eindhoven Netherlands 5600 MB 扬州广播电视大学邗江分校江苏扬州225009

水力损失计算是泵装置性能预测的基础,文中给出了低扬程泵装置各过流部件水力损失计算公式,指出非设计工况下进水流道损失修正和出水流道环量损失的概念,有助于理解泵段性能与泵装置性能的差异。系统总结了基于性能预测和流动分析的低... 详细信息

水力损失计算是泵装置性能预测的基础,文中给出了低扬程泵装置各过流部件水力损失计算公式,指出非设计工况下进水流道损失修正和出水流道环量损失的概念,有助于理解泵段性能与泵装置性能的差异。系统总结了基于性能预测和流动分析的低扬程泵装置水力设计流程,对南水北调泵站设计和建设具有一定的指导意义。

关键词：泵装置性能预测水力损失水力设计流程

Numerical investigation on the mechanism of impeller hub corner separation flow and induced energy loss in the bulb tubular pump

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Journal of Hydrodynamics 2023年第2期35卷 252-267页

作者： Long-yue Sun Qiang pan De-sheng Zhang Rui-jie Zhao b.p.m.(bart)van esch Research Center of Fluid machinery Engineering and Technology Jiangsu UniversityZhenjiang212013China Wenling Fluid machinery Technology Institute of Jiangsu University Wenling317525China Department of mechanical Engineering Eindhoven University of TechnologyEindhovenThe Netherlands Shimge pump Industry(Zhejiang)Co. Ltd.Wenling317525China

Impeller hub corner separation flow(IHCS)has a significant influence on energy conversion of the bulb tubular pump,and its unsteady characteristics are investigated with CFD-based *** generation mechanism and power loss characteristics of IHCS are investigated by the entropy production method and pressure fluctuation *** main cause can be attributed to the large transverse pressure gradient near the hub at the trailing edge of the impeller,which is aggravated by the circumferential movement trend and the diffuser reverse flow,while the IHCS is significantly weakened with increased flow *** undesirable flow behavior is more likely to cause a significant increase in energy loss near the hub region compared to that in the rim *** relative vortex stretching induced by the velocity gradient is the main cause of the horn-like vortex(HLV),and its intensity and resulting energy loss tend to decrease along the vortex *** HLV changes the dominant frequency of the pressure fluctuations in the nearby flow field,the value of which increases from 1fr(the blade passing frequency)to 2fr with increased amplitude,mainly due to the lower pressure regions on the impeller suction surface(SS)and HLV vortex *** to the effect of rotor-stator interaction(RSI),the HLVs generated between two adjacent impeller blades are cut into several sections by the diffuser vanes and propagate and dissipate along the mainstream direction.

关键词： bulb tubular pump corner separation entropy production pressure fluctuation visualization analysis

Numerical analysis of cavitation shedding flow around a three-dimensional hydrofoil using an improved filter-based model

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Journal of Hydrodynamics 2017年第2期29卷 361-375页

作者：张德胜施卫东张光建陈健 b.p.m.(bart)van esch Research Center of Fluid machinery Engineering and Technology Jiangsu UniversityZhenjiang 212013China Department of mechanical Engineering Eindhoven University of TechnologyEindhoven 5600MBTheNetherlands

The cavitation shedding flow around a 3-D Clark-Y hydrofoil is simulated by using an improved filter-based model （Fbm） and a mass transfer cavitation model with the consideration of the maximum density ratio effect between the liquid and the vapor. The unsteady cloud cavity shedding features around the Clark-Y hydrofoil are accurately captured based on an improved Fbm model and a suitable maximum density ratio. Numerical results show that the predicted cavitation patterns and evolutions compare well with the experimental visualizations, and the prediction errors of the time-averaged lift coefficient, drag coefficient and Strouhal number St for the cavitation number o- = 0.8, the angle of attack a= 8°at a Reynolds number Re = 7 x 10^5 are only 3.29%, 2.36% and 9.58%, respectively. It is observed that the cavitation shedding flow patterns are closely associated with the vortex structures identified by the Q- criterion method. The predicted cloud cavitation shedding flow shows clearly three typical stages：（1） Initiation of the attached sheet cavity, the growth toward the trailing edge. （2） The formation and development of the re-entrant jet flow. （3） Large scale cloud cavity sheds downstream. Numerical results also indicate that the non-uniform adverse pressure gradient is the main driving force of the re-entrant jet, which results in the U-shaped cavity and the 3-D bubbly structure during the cloud cavity shedding.

关键词： Cloud cavitation shedding flow filter-based model turbulent viscosity Clark-Y hydrofoil

Numerical analysis of the unsteady behavior of cloud cavitation around a hydrofoil based on an improved filter-based model

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Journal of Hydrodynamics 2015年第5期27卷 795-808页

作者：张德胜王海宇施卫东张光建 van esch b.p.m.(bart) Research Center of Fluid machinery Engineering and Technology Jiangsu University Department of mechanical Engineering Eindhoven University of Technology

The unsteady cavitation evolution around the Clark-Y hydrofoil is investigated in this paper, by using an improved filter-base model（Fbm） with the density correction method（DCm）. To improve the prediction accuracy, the filter scale is adjusted based on the grid size. The numerical results show that a small filter scale is crucial for the unsteady simulations of the cavity shedding flow. The hybrid method that combines the Fbm and the DCm could help to limit the overprediction of the turbulent viscosity in the cavitation region on the wall of the hydrofoil and in the wake. The large value of the maximum density ratio ρ1 /ρv, clip promotes the mass transfer rate between the liquid phase and the vapor phase, which results in a large sheet cavity length and the vapor fraction rise inside the cavity. The cavity patterns predicted by the improved method are verified by the experimental visualizations. The time-average lift, the drag coefficient and the primary oscillating frequency St for the cavitation number σ= 0.8, the angle of attack, α= 8°, at a Reynolds number Re= 7×10^5 are 0.735, 0.115 and 0.183, respectively, and the predicted errors are 3.29%, 3.36% and 8.93%. The typical three stages in one revolution are well-captured, including the initiation of the sheet/attached cavity, the growth toward the trailing edge（TE） with the development of the re-entrant jet flow, and the large scale cloud cavity shedding. It is observed that the cloud cavity shedding flow induces the vortex pairs of the TE vortices in the wake and the shedding vortices. The positive vorticity vortex of the re-entrant jet and the TE vortices interacts and merges with the negative vorticity vortex of the leading edge（LE） cavity to produce the shedding flow.

关键词： filter-based model(Fbm) density correction method cloud cavitation hydrofoil unsteady behavior

Improvement of the SST γ-Re_(θt) transition model for flows along a curved hydrofoil

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Journal of Hydrodynamics 2021年第3期33卷 520-533页

作者： Chang-liang Ye Chao-yue Wang Dan Zi Yuan Tang bart.p.m.van esch Fu-jun Wan College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China Department of mechanical Engineering Eindhoven University of TechnologyEindhovenThe Netherlands beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing100083China

The transition in the boundary-layer flow affects the hydrodynamic performances of hydraulic machineries,as the key components in the ship propulsion *** shear stress transfer(SST)γ-Re_(θt) transition model is an important prediction tool in the boundary layer simulation for *** present paper improves the prediction accuracy of the SST γ-Re_(θt) model for the boundary layers along a curved *** SST γ-Re_(θt) transition model for the flows along a curved hydrofoil is improved by introducing a correction to the transition onset Reynolds number Reθ***,the transition onset locations for the flows along the hydrofoils of different curvatures are obtained by the large eddy simulation and by using the SST γ-Re_(θt) ***,the transition onset Reynolds numbers Reθt in the SST γ-Re_(θt) model is modified to ensure that the predicted boundary layer parameters are consistent with the large eddy simulation(LES)*** correlation function between the curvature ratio and the modified transition onset Reynolds number is obtained and subsequently used as a correction function in the original SST γ-Re_(θt) *** test cases are used to evaluate the performance of the improved SST γ-Re_(θt) *** the NACA0035 hydrofoil with a large curvature,the predicted results obtained by using the improved SST γ-Re_(θt) model are quite consistent with the experimental data,which indicates the advantages of the improved model in predicting the boundary layer transition along a *** the test cases of the NACA0016 hydrofoil with a mild curvature and the NACA66(mod)-312 hydrofoil,the prediction results of the improved model are in good agreement with the experimental results in terms of the wake region and the boundary layer parameters,which indicates that the improved SST γ-Re_(θt) model can serve as a powerful tool in the design and the optimization of hydraulic machineries such as the waterjet pumps or the naval propellers.

关键词： Hydrodynamics transition model curvature effect hydrofoil boundary layer transition

Role of amygdala in mediating sexual and emotional behavior via coupled nitric oxide release

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Acta pharmacologica Sinica 2005年第4期26卷 389-395页

作者： Elliott SALAmON Tobias esch George b STEFANO Neuroscience Research Institute State University of New York College at Old Westbury Old Westbury New York 11568 USA Neuroscience Research Institute State University of New York College at Old Westbury Old Westbury New York 11568 USA Charit University medicine berlin Institute for General practice and Family medicine Schumannstrasse 10117 berlin Germany Neuroscience Research Institute State University of New York College at Old Westbury Old Westbury New York 11568 USA

Although the anatomical configuration of the amygdala has been studied a greatdeal,very little research has been conducted on understanding the precise mecha-nism by which this emotional regulatory center exerts its control on emotional andsexual *** applying research methodology from the Neuroscience Re-search Institute,State University of New York,College at Old Westbury,we in-tended to demonstrate that much of the mediated effects of the amygdala,specifi-cally the regulation of the male and female sexual response cycles,as well asrelated emotional considerations,exert their effects coupled to nitric oxide (NO)***,by using current anatomical and histological data,wedemonstrated that amygdalar tissue rich in endocannabinoid and opiate,as wellas catecholamine,receptors could exert its neurochemical effects within an NO-mediated *** paradigm,together with the existence of estrogen andandrogen signaling within the amygdala,further lends credence to our *** begin with a brief anatomical and functional review of amygdalarfunction,and then proceed to demonstrate its relationship with NO.

关键词： amygdala sex nitric oxide morphine emotion

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泵站开敞式进水池流动特性数值模拟

扬州大学学报（自然科学版） 2009年第2期12卷 58-61页

作者：成立刘超 van esch b p m 周济人金燕扬州大学水利科学与工程学院江苏扬州225009 Dept of mech Engin Eindhoven Univ of TechEindhovenNetherlands 5600 MB

为深入研究开敞式进水池的内部流态,基于定常不可压流体的控制方程和重整化群(RNG)湍流模型,采用CFD技术,通过SImpLEC算法,计算其三维流动,获得整体流场结果,揭示了泵站进水池水流运动规律.研究表明,进水池内流动可分为进水池直段、喇... 详细信息

为深入研究开敞式进水池的内部流态,基于定常不可压流体的控制方程和重整化群(RNG)湍流模型,采用CFD技术,通过SImpLEC算法,计算其三维流动,获得整体流场结果,揭示了泵站进水池水流运动规律.研究表明,进水池内流动可分为进水池直段、喇叭口吸水和进水管内流动3个阶段,各阶段的流动特征不同.在进水池喇叭管的下方、进水池水面附近吸水管靠后壁处、进水池两个边角及侧边壁下方靠近底部处等区域是易形成旋涡的主要位置,须采用措施进行预防.

关键词：进水池泵站流态数值模拟

Numerical investigation and optimization of the fish mortality in an axial-flow pump based on a blade strike model

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Numerical investigation and optimization of the fish mortali...

The natural analgesic conolidine targets the newly identified opioid scavenger ACKR3/CXCR7

第二十九届全国水动力学研讨会

作者： pAN Qiang ZHANG De-sheng SHI Wei-dong ZHAO Ru-ijie van esch b.p.m Research Center of Fluid machinery Engineering and Technology Jiangsu University Department of mechanical Engineering Eindhoven University of Technology

In an effort to avert fish injury and mortality during passage through pumping stations,a validated blade strike model for fish damage is integrated into a CFD-based design method for *** paper describes the design of a fish-friendly axial-flow *** a first step,the hydraulic and fish handling performance of an existing,axial flow pump is *** pump employs a conventional,high specific speed impeller with a diameter of 1.26 m and operates at a head of 4 *** hydraulic performance is in close agreement with *** expected,the calculated blade strike mortality rate is up to 65%at design condition for rainbow trout with a length of 150 ***,the design of the pump was adapted step-wise in order to reduce fish mortality without compromising its hydraulic *** the final design,the risk of fish mortality has reduced considerably to a calculated value of 15%.Results show that the performance of the fish-friendly pump is still acceptable for practical application.

关键词： blade strike model axial flow pump fish mortality hydraulic performance cavitation CFD

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Signal Transduction and Targeted Therapy 2021年第7期6卷 1966-1968页

作者： martyna Szpakowska Ann m.Decker max meyrath Christie b.palmer bruce E.blough Ojas A.Namjoshi Andy Chevigne Immuno-pharmacology and Interactomics Department of Infection and ImmunityLuxembourg Institute of Health(LIH)Esch-sur-AlzetteLuxembourg Center for Drug Discovery RTI InternationalDurhamNCUSA Faculty of Science Technology and MedicineUniversity of LuxembourgEsch-sur-AlzetteLuxembourg

Dear Editor,The atypical chemokine receptor ACKR3 has recently been reported to act as an opioid scavenger with unique negative regulatory properties towards different families of opioid ***,we show that conolidine,a natural analgesic alkaloid used in traditional Chinese medicine,targets ACKR3,thereby providing additional proof of a correlation between ACKR3 and pain modulation and opening alternative therapeutic avenues for the treatment of chronic pain.

关键词： CXCR7 opioid analgesic