Influence of Guide Vane Setting in Pump Mode on Performance Characteristics of a Pump-Turbine

Deyou Li,Hongjie Wang,Torbjørn K. Nielsen,Ruzhi Gong,Xianzhu Wei,Daqing Qin 한국유체기계학회 2017 International journal of fluid machinery and syste Vol.10 No.2

Performance characteristics in pump mode of pump-turbines are vital for the safe and effective operation of pumped storage power plants. However, the head characteristics are different under different guide vane openings. In this paper, 3-D steady simulations were performed under 13mm, 19mm and 25mm guide vane openings. Three groups of operating points under the three GVOs were chosen based on experimental validation to investigate the influence of guide vane setting on flow patterns upstream and downstream. The results reveal that, the guide vane setting will obviously change the flow pattern downstream, which in turn influences the flow upstream. It shows a strong effect on hydraulic loss (power dissipation) in the guide and stay vanes. It is also found that the hydraulic loss mainly comes from the flow separation and vortices. In addition, in some operating conditions, the change of guide vane opening will change the flow angle at the runner inlet and outlet, which will change the Euler momentum (power input). The joint action of Euler momentum and hydraulic loss results in the change of the head characteristics.

Analysis of vorticity dynamics for hump characteristics of a pump turbine model

Deyou Li,Ruzhi Gong,Hongjie Wang,Lei Han,Xianzhu Wei,Daqing Qin 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.8

Conventional parameters based on CFD methodology for the investigation on hump characteristics of a pump turbine cannot reflect the dynamic interaction mechanism between the runner and the fluid. This research presents a dynamic interaction mechanism of a pump turbine operating in the hump region. First, vorticity dynamic parameters were obtained based on the theory of vorticity dynamics. Second, 3-D unsteady flow simulations were performed in a full pump turbine model using the SST k-ω turbulence model, and numerical results have a good agreement with the experiments. Then, analysis was carried out to determine the relation between the vorticity dynamic parameters and hump characteristics. The results indicate that the theory of vorticity dynamics has an advantage in evaluating the dynamic performance of a pump turbine. The energy transfer between the runner and the fluid is through vorticity dynamic parameterspressure and friction terms, in which the pressure term accounts for the most. Furthermore, vortex generation mainly results from the skin friction. Combining vorticity dynamic analysis with the method of Q-criterion indicates that hump characteristics are related to the reduction of the surface normal pressure work and vortex motion on the suction surfaces close to the leading edges in the runner, and the increase of skin friction work in the stay-guide vanes.

Economical Low-Temperature Bleaching of Cotton Fabric Using an Activated Peroxide System Coupling Cupric Ions with Bicarbonate

Deyou Yu,Minghua Wu,Junxiong Lin,Jintao Zhu 한국섬유공학회 2018 Fibers and polymers Vol.19 No.9

Conventional cotton bleaching is highly energy-intensive, water-dependent, and textile-damaging. The technologies currently used to achieve low-temperature bleaching always include a conflict between effectiveness and cost. This study represents an economically efficient process for cotton bleaching with H2O2 at low temperature. A novel system that couples Cu2+ with HCO3 −, has been developed to activate cotton bleaching. Factors that influence the bleaching performance were investigated, including the bleaching temperature and initial concentrations of the components (H2O2, NaHCO3 and Cu2+). The experimental results indicated that the Cu2+-HCO3 −/H2O2 system had a lower operating cost and higher bleaching efficiency than conventional and TAED-activated systems. Additionally, the bleaching bath exhibited excellent reusability, further strengthening its feasibility for industrial applications. The results of HO• scavenging and Cu2+ monitoring experiments implied that the bleaching active species might be the Cu(III) species rather than HO•. This novel system provides a simple, effective, and cost-efficient method for practical bleaching.

In Vitro and In Vivo Study on the Effect of Lysosome-associated Protein Transmembrane 4 Beta on the Progression of Breast Cancer

Deyou Tao,Junqing Liang,Yihong Pan,Yanting Zhou,Ying Feng,Lin Zhang,Jingjing Xu,Hui Wang,Ping He,Jie Yao,Yang Zhao,Qinjie Ning,Wen Wang,Wei Jiang,Jing Zheng,Xia Wu 한국유방암학회 2019 Journal of breast cancer Vol.22 No.3

Purpose: Although the effect of lysosome-associated protein transmembrane 4 beta (LAPTM4B) on the proliferation, migration, and invasion of breast cancer (BC) cells has already been studied, its specific role in BC progression is still elusive. Here, we evaluated the effect of different levels of LAPTM4B expression on the proliferation, invasion, adhesion, and tumor formation abilities of BC cells in vitro, as well as on breast tumor progression in vivo. Methods: We investigated the influence of LAPTM4B expression on MCF-7 cell proliferation, invasion, adhesion, and tube formation abilities in vitro through its overexpression or knockdown and on breast tumor progression in vivo. Results: Cell growth curves and colony formation assays showed that LAPTM4B promoted the proliferation of breast tumor cells. Cell cycle analysis results revealed that LAPTM4B promoted the entry of cells from the G1 into the S phase. Transwell invasion and cell extracellular matrix adhesion assays showed that LAPTM4B overexpression increased the invasion and adhesion capabilities of MCF-7 cells. More branches were observed in MCF-7 cells overexpressing LAPTM4B under an electron microscope. In comparison with LAPTM4B overexpression, LAPTM4B knockdown decreased the expression of vascular endothelial growth factor-A and significantly inhibited the vasculogenic tube formation ability of tumors. These results were also verified with western blot analysis. Conclusion: LAPTM4B promoted the proliferation of MCF-7 cells through the downregulation of p21 (WAF1/CIP1) and caspase-3, and induced cell invasion, adhesion, and angiogenesis through the upregulation of hypoxia-inducible factor 1 alpha, matrix metalloproteinase 2 (MMP2), and MMP9 expression. This specific role deems LAPTM4B as a potential therapeutic target for BC treatment.

Influence of axial clearance on the performance characteristics of a turbopump

Deyou Li,Zhipeng Ren,Rong Fan,Yafei Chai,Ruzhi Gong,Hongjie Wang 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.10

To evaluate the influence of axial clearance on the performance characteristics in turbopumps, numerical simulations of an entire flow passage were carried out. The simulations were validated by performance characteristic experiments. The progress of the reciprocating axial movement in the rotor between the front and back covers was disassembled into five fixed clearances groups. Hump characteristic occurs at the same flow rate under these clearances groups. The hydraulic loss of the inducer-impeller was clearly influenced by the clearances. In particular, the hydraulic loss of the impeller changes significantly at the low flow rate under the ±0.3 mm clearance. With the increase of the flow rate, the effect of the clearance change on the flow is weakened. An innovative entropy production analysis was also performed. The distribution of the high local entropy production rate at the impeller inlet under the 0 mm clearance and at the impeller outlet under the −0.15 mm and −0.3 mm clearances overlapped with the vortex caused by flow separation, and the counterpart at the back cover is concentrated around the clearance structures, thereby leading to high hydraulic loss.

A new prenylated isoflavone from the seeds of <i>Millettia ferruginea</i> ssp. <i>ferruginea</i>

Deyou, T.,Jang, Y.P. Elsevier 2018 South African journal of botany : official journal Vol.117 No.-

<P><B>Abstract</B></P> <P>From the dichloromethane/methanol (1:1, <I>v</I>/v) extract of the seeds of <I>Millettia ferruginea</I> ssp. <I>ferruginea</I>, one new isoflavone named; 6,7-dimethoxy-3′,4′-methylenedioxy-8-(3,3-dimethylallyl)isoflavone was identified along with five known isoflavones, a chalcone and a rotenoid. The structures of the isolated compounds were established using NMR (Nuclear Magnetic Resonance) spectroscopic, mass spectrometric analyses, and comparison with the values in the literature.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Chromatographic separation of crude extract of the seeds of <I>Millettia ferruginea</I> ssp. <I>ferruginea</I> afforded eight secondary metabolites. </LI> <LI> The isolated compounds belong to the class of isoflavonoid, chalconoid and rotenoid. </LI> <LI> One of the isolated compounds is reported here to be new. </LI> </UL> </P>

Influence of Guide Vane Setting in Pump Mode on Performance Characteristics of a Pump-Turbine

Li, Deyou,Wang, Hongjie,Nielsen, Torbjorn K.,Gong, Ruzhi,Wei, Xianzhu,Qin, Daqing Korean Society for Fluid machinery 2017 International journal of fluid machinery and syste Vol.10 No.2

Performance characteristics in pump mode of pump-turbines are vital for the safe and effective operation of pumped storage power plants. However, the head characteristics are different under different guide vane openings. In this paper, 3-D steady simulations were performed under 13mm, 19mm and 25mm guide vane openings. Three groups of operating points under the three GVOs were chosen based on experimental validation to investigate the influence of guide vane setting on flow patterns upstream and downstream. The results reveal that, the guide vane setting will obviously change the flow pattern downstream, which in turn influences the flow upstream. It shows a strong effect on hydraulic loss (power dissipation) in the guide and stay vanes. It is also found that the hydraulic loss mainly comes from the flow separation and vortices. In addition, in some operating conditions, the change of guide vane opening will change the flow angle at the runner inlet and outlet, which will change the Euler momentum (power input). The joint action of Euler momentum and hydraulic loss results in the change of the head characteristics.

Analysis of transient flow in a pump-turbine during the load rejection process

Xiaolong Fu,Deyou Li,Hongjie Wang,Guanghui Zhang,Zhenggui Li,Xianzhu Wei 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.5

The transient flow in pump-turbines during the load rejection process is very complex. However, few studies have been conducted on three-dimensional (3-D) numerical simulation. Hence, we simulated 3-D transient turbulent flow in a pump-turbine during the load rejection process using the calculation method of coupling the flow with the rotor motion of rigid body. To simulate the unsteady boundary conditions, the dynamic closing process of the guide vanes was simulated with the dynamic mesh technology. The boundary conditions at the spiral-casing inlet and the draft tube outlet were determined using the user defined functions (UDF) according to the experimental data. The numerical results of the rotational speeds show a good agreement with the experimental data. Then, the complex transient flow in the pump-turbine during the load rejection process was analyzed based on the numerical results. The results show that there are severe unsteady vortex flows in the vaneless space near the conditions under which the hydraulic torque on the runner equals to zero. When the pump-turbine operates into the maximum reverse discharge condition in the reverse pump operating process, the unsteady vortex flows in the vaneless space are instantaneously impacted into the region between the guide vanes and the stay vanes by the sudden reverse flows. The formation and development mechanism of the unsteady vortex flow in the vaneless space is associated with the distribution characteristic of the velocity field.

GEOLOGICAL SCIENCES SESSION ( NATURAL HISTORY ) : Mesozoic Volcanic Rocks and its Tectonic Setting in Manzhouli - suifenhe Geoscience Transect ( M-S GT ) Northeast China

(Wenliang Xu),(Deyou Sun) 자연사.미래환경학회(구.자연사환경학회) 1994 INTERNATIONAL SYMPOSIUM ON GEOLOGY , ENVIRONMENTS Vol.- No.-

Larvicidal activities of the stem bark extract and rotenoids of Millettia usaramensis subspecies usaramensis on Aedes aegypti L. (Diptera: Culicidae)

Carren M. Bosire,Tsegaye Deyou,Jacques M. Kabaru,DennisM. Kimata,Abiy Yenesew 한국응용곤충학회 2014 Journal of Asia-Pacific Entomology Vol.17 No.3

The dichloromethane/methanol (1:1) extract of the stem bark of Millettia usaramensis subspecies usaramensiswas tested for its larvicidal activity against the 4th instar Aedes aegypti larvae and demonstrated activity withLC50 value of 50.8±0.06 μg/mL at 48 h. Compounds isolated from the extractwere also tested for their larvicidalactivities, and the rotenoid usararotenoid-A (LC50 4.3 ± 0.8 μg/mL at 48 h) was identified as the most activeprinciple. This compound appears to be the first rotenoid having a trans-B/C ring junction and methylenedioxygroup at C-2/C-3 with high larvicidal activity. Related rotenoids with the same configuration at the B/C-ringjunction did not show significant activity at 100 μg/mL.