The Experts below are selected from a list of 80832 Experts worldwide ranked by ideXlab platform
Hucan Hou - One of the best experts on this subject based on the ideXlab platform.
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theory and application of two dimension viscous Hydraulic Design of the ultra low specific speed centrifugal pump
2020Co-Authors: Cong Wang, Yongxue Zhang, Hucan Hou, Zhiyi YuanAbstract:Low efficiency and bad cavitation performance restrict the development of the ultra-low specific-speed centrifugal pump (ULSSCP). In this research, combined turbulent boundary layer theory with two-dimension Design and two-dimension viscous Hydraulic Design method has been proposed to reDesign a ULSSCP. Through the solution of the displacement thickness in the boundary layer, a less curved blade profile with a larger outlet angle was obtained. Then the Hydraulic and cavitation performance of the reference pump and the Designed pump were numerically studied. The comparison of performance of the reference pump calculated by the numerical and experimental results revealed a better agreement. Research shows that the average Hydraulic efficiency and head of the Designed pump improve by 2.9% and 3.3%, respectively. Besides, the Designed pump has a better cavitation performance. Finally, through the internal flow analysis with entropy production diagnostic model, a 24.8% drop in head loss occurred in the Designe...
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theory and application of two dimension viscous Hydraulic Design of the ultra low specific speed centrifugal pump
2020Co-Authors: Cong Wang, Yongxue Zhang, Hucan Hou, Zhiyi YuanAbstract:Low efficiency and bad cavitation performance restrict the development of the ultra-low specific-speed centrifugal pump (ULSSCP). In this research, combined turbulent boundary layer theory with two...
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optimal Hydraulic Design of an ultra low specific speed centrifugal pump based on the local entropy production theory
2019Co-Authors: Yongxue Zhang, Xin Zhou, Hucan Hou, Zhitao Zuo, Haisheng ChenAbstract:The ultra-low specific speed centrifugal pump has been widely applied in aerospace engineering, metallurgy, and other industrial fields. However, its Hydraulic Design lacks specialized theory and m...
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the optimal Hydraulic Design of centrifugal impeller using genetic algorithm with bvf
2014Co-Authors: Xin Zhou, Yongxue Zhang, Hucan HouAbstract:Derived from idea of combining the advantages of two-dimensional Hydraulic Design theory, genetic algorithm, and boundary vorticity flux diagnosis, an optimal Hydraulic Design method of centrifugal pump impeller was developed. Given Design parameters, the desired optimal centrifugal impeller can be obtained after several iterations by this method. Another 5 impellers with the same parameters were also Designed by using single arc, double arcs, triple arcs, logarithmic spiral, and linear-variable angle spiral as blade profiles to make comparisons. Using Reynolds averaged N-S equations with a RNG k-e two-equation turbulence model and log-law wall function to solve 3D turbulent flow field in the flow channel between blades of 6 Designed impellers by CFD code FLUENT, the investigation on velocity distributions, pressure distributions, boundary vorticity flux distributions on blade surfaces, and Hydraulic performance of impellers was presented and the comparisons of impellers by different Design methods were demonstrated. The results showed that the Hydraulic performance of impeller Designed by this method is much better than the other 5 impellers under Design operation condition with almost the same head, higher efficiency, and lower rotating torque, which implied less Hydraulic loss and energy consumption.
Hubert Chanson - One of the best experts on this subject based on the ideXlab platform.
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Hydraulic Design of stepped spillways and downstream energy dissipators for embankment dams
2007Co-Authors: Carlos A Gonzalez, Hubert ChansonAbstract:In recent years, the Design flows of many dams were re-evaluated, often resulting in discharges larger than the original Design. In many cases, the occurrence of the revised flows could result in dam overtopping because of insufficient storage and spillway capacity. An experimental study was conducted herein to gain a better understanding of the flow properties in stepped chutes with slopes typical of embankment dams. The work was based upon a Froude similitude in large-size experimental facilities. A total of 10 configurations were tested including smooth steps, steps equipped with devices to enhance energy dissipation and rough steps. The present results yield a new Design procedure. The Design method includes some key issues not foreseen in prior studies : e.g., gradually varied flow, type of flow regime, flow resistance. It is believed that the outcomes are valid for a wide range of chute geometry and flow conditions typical of embankment chutes.
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teaching Hydraulic Design in an australian undergraduate civil engineering curriculum
2001Co-Authors: Hubert ChansonAbstract:Since the early European settlements, Australia's economy has been highly dependent upon its water supply, although limited because of the dry climate. Today, the Australian continent is equipped with a large number of Hydraulic structures per capita, and Hydraulic engineering expertise is critical to future developments. In the universities, the civil engineering and environmental engineering undergraduate courses include a significant number of fluid mechanics and Hydraulics subjects, including an introduction to Hydraulic Design. At the University of Queensland, the teaching of Hydraulic Design is focused on the sound application of the basic principles of fluid mechanics. Basic applications include the Hydraulic Design of spillways and culverts. Each type of Design is supported by a series of lectures and a case study involving homework, a field visit, and a series of tutorials. Practical classes (laboratory and field visit) are an indispensable complement of the lectures. The subject assessment is based upon a combination of homework, practicals, and end-of-semester examination grades.
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Hydraulic Design of stepped spillways and downstream energy dissipators
2001Co-Authors: Hubert ChansonAbstract:Stepped channels and spillways have been used for centuries. Recently, new construction materials, (e.g. RCC, gabions) and Design techniques (e.g. embankment overtopping protection) have increased the interest in stepped chutes. The steps produce considerable energy dissipation along the chute and reduce the size of the required downstream energy dissipation basin. This paper reviews the characteristics of modern stepped spillways. The basic flow patterns are described. Basic equations are developed, taking into account the free surface aeration in skimming flows. The calculations of the residual energy to be dissipated in the downstream dissipator are discussed. Simple Design guidelines for the downstream energy dissipators are provided for use by professionals.
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Introducing originality and innovation in engineering teaching: The Hydraulic Design of culverts
2000Co-Authors: Hubert ChansonAbstract:Recently, the teaching of engineering Design has become a presentation of standards and codes rather than the learning of sound Design practices. Too many students request formulae and equations to solve a Design exercise and they fail to develop any Design originality. The present student attitude leads to young graduate engineers without critical ability and innovative flair. The writer has developed an innovative Hydraulic Design exercise based upon culvert Design. Each Design exercise could lead to more than one correct Design per student in the class. Students have to learn basic Design calculations based upon lecture material, notes, field visits and laboratory experiment. The practical component (laboratory, field visit) contributes significantly to their understanding of the complete system, including some basic safety and professional issues.
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Hydraulic Design of stepped cascades channels weirs and spillways
1994Co-Authors: Hubert ChansonAbstract:Stepped channels and spillways are used since more than 2,500 years. Recently, new construction materials (e.g. RCC, gabions) have increased the interest for stepped chutes. The steps increase significantly the rate of energy dissipation taking place along the chute and reduce the size of the required downstream energy dissipation basin. Stepped cascades are used also in water treatment plants to enhance the air-water transfer of atmospheric gases (e.g. oxygen, nitrogen) and of volatile organic components (VOC). A first part describes the historical progress of stepped channels and spillways from the Antiquity up to today. Then the monograph reviews the Hydraulic characteristics of stepped channel flows. Two different flow regimes can take place : nappe flow regime for small discharges and flat channel slopes, and skimming flow regime. The Hydraulics of each flow regime is described. The effects of flow aeration and air bubble entrainment are discussed. Further the process of air-water gas transfer taking place above stepped chute is described. Later practical examples of Hydraulic Design are presented : e.g. stepped fountains, stepped weirs, gabion stepped spillways, earth dam spillways with precast concrete blocks, roller compacted concrete (RCC) weirs, debris dams. At the end, the author presents a critical review of the risks of accidents and failures with stepped channels. It is shown that the hydrodynamic forces on the step faces are much larger than on smooth chute bottoms.
Suizheng Qiu - One of the best experts on this subject based on the ideXlab platform.
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thermal Hydraulic Design and analysis of a small modular molten salt reactor msr with solid fuel
2018Co-Authors: Chenglong Wang, Dalin Zhang, Wenxi Tian, Kaichao Sun, Suizheng QiuAbstract:Summary A 20 MWth, 540 EFPD once through fuel cycle small modular molten salt reactor with solid fuel is proposed by Massachusetts Institute of Technology for off-grid applications. In this paper, various thermal-Hydraulic analysis methods including computational fluid dynamics, Reactor Excursion Leak Analysis Program (RELAP5), and DAKOTA are adopted step-by-step for the reactor Design based on the neutronic analysis results. First, 1/12th full core thermal Hydraulic analysis is performed by using STAR CCM+ with most conservative considerations. Second, the transient safety behaviors of reactor system with risky assumptions are conducted by using REALP5. Finally, due to the unknown factors affecting reactor thermal-Hydraulic characteristics, the uncertainty quantification and sensitivity analysis for the Designed reactor is performed with DAKOTA code coupled with RELAP5. Numerical results show that a more uniform temperature distribution with reduced peak temperatures of fuel and coolant across the reactor core has been achieved. Enough safety margin is maintained even under most severe transient accident. The uncertainties in the heat transfer coefficient and helium gap conductivity factor are the most remarkable contributors to the statistical results of peaking fuel temperature. All above results preliminarily indicate the feasibility of the current small modular molten salt reactor Design and provide the further optimization direction from reactor thermal-Hydraulic prospective.
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thermal Hydraulic Design of water cooled pressure tube blanket for a fusion driven subcritical reactor
2013Co-Authors: Xinli Gao, Wenxi Tian, Suizheng QiuAbstract:Abstract A Water-cooled Pressure Tube Energy production blanket (WPTE) for fusion driven subcritical reactor has been Designed to achieve 3000 MW thermal power with self-sustaining tritium cycle. Pressurized water has great advantages in energy production; however the high pressure may cause some severe structural Design issues. This paper proposes a new concept of water-cooled blanket. To solve the problem of the high pressure of the coolant, the pressure tube was adopted in the Design and in the meantime, the thickness of the first wall can be significantly reduced as result of adopting pressure tube. The numerically simulating and calculating of temperature, stress distribution and flow analyses were carried out and the feasibility of using water as coolant was discussed. The results demonstrated the engineering feasibility of the water-cooled fusion–fission hybrid reactor blanket module.
Yongxue Zhang - One of the best experts on this subject based on the ideXlab platform.
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theory and application of two dimension viscous Hydraulic Design of the ultra low specific speed centrifugal pump
2020Co-Authors: Cong Wang, Yongxue Zhang, Hucan Hou, Zhiyi YuanAbstract:Low efficiency and bad cavitation performance restrict the development of the ultra-low specific-speed centrifugal pump (ULSSCP). In this research, combined turbulent boundary layer theory with two-dimension Design and two-dimension viscous Hydraulic Design method has been proposed to reDesign a ULSSCP. Through the solution of the displacement thickness in the boundary layer, a less curved blade profile with a larger outlet angle was obtained. Then the Hydraulic and cavitation performance of the reference pump and the Designed pump were numerically studied. The comparison of performance of the reference pump calculated by the numerical and experimental results revealed a better agreement. Research shows that the average Hydraulic efficiency and head of the Designed pump improve by 2.9% and 3.3%, respectively. Besides, the Designed pump has a better cavitation performance. Finally, through the internal flow analysis with entropy production diagnostic model, a 24.8% drop in head loss occurred in the Designe...
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theory and application of two dimension viscous Hydraulic Design of the ultra low specific speed centrifugal pump
2020Co-Authors: Cong Wang, Yongxue Zhang, Hucan Hou, Zhiyi YuanAbstract:Low efficiency and bad cavitation performance restrict the development of the ultra-low specific-speed centrifugal pump (ULSSCP). In this research, combined turbulent boundary layer theory with two...
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optimal Hydraulic Design of an ultra low specific speed centrifugal pump based on the local entropy production theory
2019Co-Authors: Yongxue Zhang, Xin Zhou, Hucan Hou, Zhitao Zuo, Haisheng ChenAbstract:The ultra-low specific speed centrifugal pump has been widely applied in aerospace engineering, metallurgy, and other industrial fields. However, its Hydraulic Design lacks specialized theory and m...
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the optimal Hydraulic Design of centrifugal impeller using genetic algorithm with bvf
2014Co-Authors: Xin Zhou, Yongxue Zhang, Hucan HouAbstract:Derived from idea of combining the advantages of two-dimensional Hydraulic Design theory, genetic algorithm, and boundary vorticity flux diagnosis, an optimal Hydraulic Design method of centrifugal pump impeller was developed. Given Design parameters, the desired optimal centrifugal impeller can be obtained after several iterations by this method. Another 5 impellers with the same parameters were also Designed by using single arc, double arcs, triple arcs, logarithmic spiral, and linear-variable angle spiral as blade profiles to make comparisons. Using Reynolds averaged N-S equations with a RNG k-e two-equation turbulence model and log-law wall function to solve 3D turbulent flow field in the flow channel between blades of 6 Designed impellers by CFD code FLUENT, the investigation on velocity distributions, pressure distributions, boundary vorticity flux distributions on blade surfaces, and Hydraulic performance of impellers was presented and the comparisons of impellers by different Design methods were demonstrated. The results showed that the Hydraulic performance of impeller Designed by this method is much better than the other 5 impellers under Design operation condition with almost the same head, higher efficiency, and lower rotating torque, which implied less Hydraulic loss and energy consumption.
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3d blade Hydraulic Design method of the rotodynamic multiphase pump impeller and performance research
2014Co-Authors: Yongxue Zhang, Jinya Zhang, Hongwu Zhu, Shujie CaiAbstract:A Hydraulic Design method of three-dimensional blade was presented to Design the blades of the rotodynamic multiphase pump. Numerical simulations and bench test were conducted to investigate the pe...
Moon Hee Chang - One of the best experts on this subject based on the ideXlab platform.
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development of a computer code oncesg for the thermal Hydraulic Design of a once through steam generator
2000Co-Authors: Juhyeon Yoon, Moon Hee ChangAbstract:Development of the conceptual Design of a 300 MWt integral reactor, SMART (System-integrated Modular Advanced ReacTor), for utilization in nuclear cogeneration plants has been completed at the Korea Atomic Energy Research Institute (KAERI). The major primary components of the SMART such as modular helical steam generators, main circulation pumps and a self regulating pressurizer are integrated into a reactor vessel. It is a common practice to employ a once-through steam generator in integral reactor Designs because of its advantages in compactness and simplicity of the flow path arrangements. In this study, a thermal Hydraulic Design and performance analysis computer code for a once-through steam generator using helically coiled tubes, ONCESG, is developed. To benchmark the developed physical models and computer code, once-through steam generators developed by other Designers are simulated and ONCESG calculated results are compared with the Design data. The overall characteristics of heat transfer area, p...
