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| 1 | SSQ系列射流施肥器水力性能试验研究显示文摘基于农业生产中水肥一体化技术的施肥要求,该研究对国内常用的SSQ系列射流施肥器进行了性能测试。以吸肥量、进出口压差等指标为研究目标进行了施肥器水力性能的分析和预测,推导了SSQ系列射流施肥器开始吸肥和吸肥效率最高时进出口压差与进口压力的关系公式。结果表明:在正常工作阶段,SSQ系列射流施肥器的吸肥量随进出口压差的增加而增大,在空化条件下达到极限工况;8种不同规格施肥器在进口压力超过0.20 MPa时才能充分发挥吸肥性能;正常工作阶段临界压差与进口压力关系公式的斜率与试验值的误差小于15%,斜率的大小主要受喉管截面和喷嘴出口截面的面积比影响;效率最高时进出口压差与进口压力关系公式的斜率与试验值的平均相对误差为17%,验证了该关系公式的合理性。该文提出的SSQ系列射流施肥器水力性能预测公式可为同类产品的设计和应用提供参考。 | 汪小珊 严海军 周凌九 徐云成 | 2020 | 农业工程学报2020，36，21： | 6 |
| 2 | Large eddy simulation of the transient cavitating vortical flow in a jet pump with special emphasis on the unstable limited operation stage显示文摘This paper studies the unsteady three-dimensional cavitating turbulent flow in a jet pump.Specifically,thefocus is on the unstable limited operation stage,and both the computational and experimental methods are used.In the experiments,the distribution of the wall pressure,as well as the evolution of cavitation over time,are obtained for a jet pump.Computation is carried out using the large eddy simulation,combined with a mass transfer cavitation model.The numerical results are compared with the experimental results,including the fundamental performances(the pressure ratio h and the efficiencyη),as well as the wall pressure distribution.Both the experimental and computational results indicate that the evolution of the cavitation over time in a jet pump is a quasi-periodic process during the unstable limited operation stage.The annular vortex cavitation inception,development and collapse predicted by the large eddy simulation agree fairly well with the experimental observations.Furthermore,the relationship between the cavitation and the vortex structure is discussed based on the numerical results,and it is shown that the development of the vortex structures in the jet pump is closely related to the evolution of the cavitation.The cavitation-vortex interaction is thoroughly analyzed based on the vorticity transport equation.This analysis reveals that the cavitation in a jet pump dramatically influences the distribution and the production of the vorticity.The process of the annular cavitation inception,development,and collapse involves a significant increase of the vorticity. | Xin-ping Long Dan Zuo Huai-yu Cheng Bin Ji | 2020 | Journal of Hydrodynamics2020，32，2： | 5 |
| 3 | 高速摄影技术分析射流式鱼泵流量对鱼运动规律影响显示文摘采用高速摄影技术初步研究了草鱼、团头鲂和鲫鱼等3种鱼类在射流式鱼泵内的运动规律,分析了鱼类逆流游动率、逆流游动过泵时间、姿态变化率及鱼类与泵壁面碰撞所受力与工作流体流量之间的关系。试验研究表明:在5种工作流体流量工况下,随着工作流体流量的增加,鱼类逆流游动率逐渐降低,过泵时间逐渐减少,姿态变化率逐渐升高,所受碰撞力逐渐升高;在工作流体流量较低时,鱼类逆流游动率超过85%,过泵时间均超过300ms,姿态变化率均小于6%,所受碰撞力在1~3N的范围内;在工作流体流量较高时,鱼类逆流游动率在50%~85%之间,过泵时间在125~175ms之间,大多数情况下姿态变化率9%~18%之间,所受碰撞力在5~7N的范围内;在试验所用3种试验鱼中,草鱼的过泵时间最长,姿态变化率最高,并在大部分工况中所受碰撞力最大。 | 徐茂森 黄斌 牟介刚 谷云庆 周佩剑 吴登昊 | 2019 | 农业工程学报2019，35，17： | 4 |
| 4 | 泵站出水池整流措施数值分析显示文摘为了改善泵站出水池内的不良水流流态,基于CFD软件,采用RNG模型和VOF方法对原设计方案及4种修改方案的出水池水流进行全流场数值模拟,得到泵站出水池内部的水流流态、流速、水位、水头损失及水头损失系数.计算结果表明,原方案出水池内流态紊乱,隧洞进水条件差,水流偏斜较为明显;纵向水面差为0.33~0.48 m,水头损失和水头损失系数相对较大.通过多个方案比较,推荐采用圆弧边墙+下移隧洞进口方案,对原方案的4处折角边墙分别调整为半径为45和36 m的圆弧,同时隧洞进口向下游移动10 m.该方案能明显改善出水池的流态,水流能较均匀地进入隧洞,纵向水面差减小明显,最大减幅为0.12 m;隧洞进口流速分布均匀度提高了10.3%,水头损失减小了14.7%.根据推荐方案进行物理模型试验,试验结果与数值模拟接近. | 王月华 王斌 王自明 周盛侄 叶龙 | 2021 | 排灌机械工程学报2021，39，3： | 3 |
| 5 | 地铁列车进站过程中活塞风对站台屏蔽门的影响——以杭州地铁为例显示文摘以活塞风为研究对象,采用SST k-ω模型进行非定常计算,研究了地铁列车进站过程中产生的活塞风对站台全封闭屏蔽门的影响.研究结果表明,在列车进站过程中,活塞风井对活塞风的疏导作用与列车位置相关,距离车头位置越近的活塞风井对活塞风的疏导作用越大;列车在进站过程中会引起屏蔽门表面压力发生变化,该压力在车头通过第一个活塞风井后达到峰值,站台屏蔽门破损风险较大,且越靠近该活塞风井的屏蔽门表面压力波动幅值越大;在列车进站过程中,活塞风井内存在着回流区,且该回流区不断发展演化,与列车对空气挤压产生的活塞风相互叠加,导致屏蔽门表面压力反复振荡. | 董梦雪 赵帅帅 | 2021 | 河南科学2021，39，10： | 2 |
| 6 | 小流量工况下混流泵涡识别及其演变规律显示文摘为了研究小流量工况下混流泵内部流动状态及涡结构的演化规律,采用大涡模拟的计算方法并结合先进的Omega涡识别方法,对某混流泵小流量工况下的涡结构进行识别,获得了叶轮内部典型涡结构的特征和演化规律,并与叶片表面的涡量生成和流动分离情况进行对比分析.研究结果表明:Omega方法克服了第二代涡识别方法需要人为调节阈值的缺陷,可以较好地识别小流量工况下混流泵内部的精细涡结构;在小流量工况下,混流泵内的叶片斜向涡带、叶尖涡和叶尖分离涡、通道涡以及尾缘脱离涡是叶轮流道内生成的典型涡结构,它们有各自独立的生成和发展过程,又相互作用,使叶轮内流场更加紊乱.本研究揭示了小流量工况下混流泵内部特有的涡结构特征与演变规律,可为包括混流泵在内的叶轮机械流场分析和性能优化提供一定的理论指导和技术支撑. | 赵斌娟 刘雨露 韩璐遥 曹可凡 陈汇龙 黄忠富 | 2023 | 排灌机械工程学报2023，41，3： | 1 |
| 7 | Numerical investigation on the drag characteristics of supercritical water flow past a sphere显示文摘Numerical simulation has become a useful approach to explore the complex physical and chemical process inside the supercritical water(SCW)fluidized bed reactor.Due to the drastic and non-linear variation of water properties near pseudocritical point,the flow field and drag coefficient of SCW flow past a cold particle are considerably different from that of conventional flow.Therefore,in this work,particle-resolved numerical investigation is conducted to study the flow field and drag characteristics under the influence of the special water properties variation.Through varying the enthalpy corresponding to the particle surface temperature,which will be called the particle surface enthalpy for short,in a wide range,it realizes the study under different properties variation tendencies.The simulated results demonstrate that the variations of drag coefficient versus Reynolds number(Re)and particle surface enthalpy are in good regularity when taking the freestream temperature as reference temperature.The drag coefficient is enhanced greatly at high enthalpy difference between particle surface and inflow,and the enhancement is mainly contributed by that of the frictional drag coefficient.Moreover,the drag coefficient variations under different pressures are in good agreement when cases are set with the same inflow and particle surface enthalpies,respectively.By fitting the simulated results,a new drag coefficient correlation is developed for Re range of 10–200 with consideration of the influence of the special properties variation.The fitting quality is good that the maximum deviation between the new correlation and simulated data is 13.92%,and the mean deviation is 3.67%. | WU ZhenQun OU GuoBiao REN YiFei JIN Hui | 2020 | Science China(Technological Sciences)2020，63，8： | 1 |
| 8 | 法制的起源夏朝的建立显示文摘 | | 2000 | 法制与社会2000，，3： | 0 |
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