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Steel Bridge Construction of Hong Kong–Zhuhai–Macao Bridge
Wen-bo Gao,Quan-ke Su,Jin-wen Zhang,Hong-bing Xie,Feng Wen,Fang Li,Ji-zhu Liu 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.5
The 55-km-long Hong Kong–Zhuhai–Macao Bridge (HZMB) is the world’s longest sea-crossing bridge, connecting Hong Kong with Zhuhai and Macao at the mouth of the Pearl River Estuary in China, comprising 22.9-km-long steel bridges. HZMB is the leading steel bridge in China, with top-level manufacturing and installation technology. This paper outlines the steel bridge construction experiences of HZMB to provide comparisons for the construction of other long sea-crossing steel bridges at home or abroad. The main considerations of construction constraints, scheme selection, structural and aesthetic design of HZMB are presented, and the following points related to new strategies in the steel bridge construction of HZMB are elaborated: (1) construction quality assurance, (2) automatic manufacturing technology, (3) large segment off shore installation, (4) eco-friendly paint (content limitation of volatile organic compounds) and new multifunctional inspection gantry, and (5) Guss Mastic Asphalt steel deck pavement system. The successful implementation of those strategies shows that the steel bridge construction of HZMB promotes improvement in the overall construction and management level of the Chinese bridge industry. The advanced experience of HZMB has opened up broad prospects for the design and construction of off shore bridge engineering in China.
Hong Feng,Yu Wan,Zhang Fan 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.2
With the aim to enhance the capability of predicting cavitating flows for conventional cavitation models, a developed alternative numerical model was proposed based on an alternative truncated Rayleigh-Plesset equation and the homogeneous flow assumption. Particularly, the effect of vortex on mass transfer was accounted in the formulation of the proposed model. Turbulent cavitating flows under various flow rates in an axial flow pump with a specific speed n s = 692 were computed and compared by the proposed and the Schnerr-Sauer models, for which the experimental results were also presented for guidance. The results show that the cavitation performance predicted by the proposed model agrees better with the experiments than that by the Schnerr-Sauer model. The effect of vortex on mass transfer results in different patterns of the tip leakage vortex (TLV) cavitation near the tip leakage. Further, the solution of the proposed model reveals the corner vortex cavitation, shear layer cavitation and TLV cavitation could be integrated into a cloud vapor at critical cavitation number, and the cloud cavity sheds and collapses periodically near trailing edge of blade.
Concept Optimization for Mechanical Product Using Genetic Algorithm
Hong-Zhong Huang,Rui-Feng Bo,Xiang-Feng Fan 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.5
Conceptual design is the first step in the overall process of product design. Its intrinsic uncertainty, imprecision, and lack of information lead to the fact that current conceptual design activities in engineering have not been computerized and very few CAD systems are available to support conceptual design. In most of the current intelligent design systems, approach of principle synthesis, such as morphology matrix, bond graphic, or design catalogues, is usually adopted to deal with the concept generation, in which optional concepts are generally combined and enumerated through function analysis. However, as a large number of concepts are generated, it is difficult to evaluate and optimize these design candidates using regular algorithm. It is necessary to develop a new approach or a tool to solve the concept generation. Generally speaking, concept generation is a problem of concept synthesis. In substance, this process of developing design candidate is a combinatorial optimization process, viz., the process of concept generation can be regarded as a solution for a state-place composed of multi-concepts. In this paper, genetic algorithm is utilized as a feasible tool to solve the problem of combinatorial optimization in concept generation, in which the encoding method of morphology matrix based on function analysis is applied, and a sequence of optimal concepts are generated through the search and iterative process which is controlled by genetic operators, including selection, crossover, mutation, and reproduction in GA. Several crucial problems on GA are discussed in this paper, such as the calculation of fitness value and the criteria for heredity termination, which have a heavy effect on selection of better concepts. The feasibility and intellectualization of the proposed approach are demonstrated with an engineering case. In this work concept generation is implemented using GA, which can facilitate not only generating several better concepts, but also selecting the best concept. Thus optimal concepts can be conveniently developed and design efficiency can be greatly improved.
Hierarchical Colored Petri Nets Based Components for Workflow Systems
Feng Zhou,Rui-Feng Bo,Hong-Zhong Huang,Dan Ling,Qiang Miao 대한기계학회 2006 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.20 No.10
Workflow systems have benefited the enterprise and customer in many aspects. But with the increasing complexity of the system, workflow design becomes a complicated and time-consuming process. In this paper, we model the system based on the Hierarchical Colored Petri Nets (HCPN) to avoid the complexity of the system, and the super nets of the model are abstracted as independent components to increase the flexibility, acceptability and maintainability of the system. Another important characteristic of this model is its convenience for reuse and workflow mining. The development process of the overhead traveling crane was given to demonstrate the proposed method.
Hong-Liang Feng,Ji-Hua Huang,Jian Yang,Shao-Kun Zhou,Rong Zhang,Yue Wang,Shu-Hai Chen 대한금속·재료학회 2017 ELECTRONIC MATERIALS LETTERS Vol.13 No.6
Ni/Ni-Sn/Ni sandwiched simulated package structures weresuccessfully bonded under low temperature and low pressure byNi-Sn transient liquid-phase sintering bonding. The results showthat, after isothermally holding for 240 min at 300 °C and 180 minat 340 °C, Sn was completely transformed into Ni3Sn4 intermetalliccompounds. When the Ni3Sn4 phases around Ni particles werepressed together, the porosity of the bonding layer increased, whichobviously differed from the normal sintering densification process. With further analysis of this phenomenon, it was found that largevolume shrinkage (14.94% at 340 °C) occurred when Ni reactedwith Sn to form Ni3Sn4, which caused void formation. Amechanistic model of the microstructural evolution in the bondinglayer was proposed. Meanwhile, the resistivity of the bonding layerwas measured and analyzed by using the four-probe method; themicrostructural evolution was well reflected by the resistivity ofthe bonding layer. The relationship between the resistivity andmicrostructure was also discussed in detail.
A Passive Lossless Soft-Switching Single Inductor Dual Buck Full-Bridge Inverter
Hong, Feng,Wu, Yu,Ye, Zunjing,Ji, Baojian,Zhou, Yufei The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2
A novel passive lossless soft-switching single inductor dual buck full-bridge inverter (PLSSIDBFBI) is presented in this paper. To accomplish this, a passive lossless snubber circuit is added to a dual buck full-bridge inverter. Therefore, the advantages of the dual buck full-bridge inverter are included in the proposed inverter, and the inverter has just one filter inductor, which can decrease the system volume and improve the integration. In addition, the passive lossless snubber circuit achieves soft-switching by its own resonance, and all of the energy stored in the passive lossless snubber circuit can be transferred to load. A comparison between eight topologies is performed in this paper, and the analysis shows that the proposed soft-switching inverter topology has high reliability and efficiency. Finally, experimental results obtained with a 1 kW prototype verify the theoretical analysis and demonstrate the prominent characteristics of a reduced switching loss and improved efficiency.
A Passive Lossless Soft-Switching Single Inductor Dual Buck Full-Bridge Inverter
Feng Hong,Yu Wu,Zunjing Ye,Baojian Ji,Yufei Zhou 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2
A novel passive lossless soft-switching single inductor dual buck full-bridge inverter (PLSSIDBFBI) is presented in this paper. To accomplish this, a passive lossless snubber circuit is added to a dual buck full-bridge inverter. Therefore, the advantages of the dual buck full-bridge inverter are included in the proposed inverter, and the inverter has just one filter inductor, which can decrease the system volume and improve the integration. In addition, the passive lossless snubber circuit achieves soft-switching by its own resonance, and all of the energy stored in the passive lossless snubber circuit can be transferred to load. A comparison between eight topologies is performed in this paper, and the analysis shows that the proposed soft-switching inverter topology has high reliability and efficiency. Finally, experimental results obtained with a 1 kW prototype verify the theoretical analysis and demonstrate the prominent characteristics of a reduced switching loss and improved efficiency.
Numerical Investigation of the Turbulent Cavitating Flow over Submerged Bodies
Hong Feng,Gao Zhenjun,Liu Lili,Yuan Jianping 한국유체기계학회 2018 International journal of fluid machinery and syste Vol.11 No.1
A numerical method for the calculation of turbulent cavitating flow over submerged objects is proposed in present work. Cavitation is modeled via a single-fluid cavitation model which is derived based on a truncated form of the Rayleigh-Plesset equation and the mixture multiphase theory. The approach has been implemented by user-define function which is widely used in ANSYS FLUENT. Detailed results are presented for sheet cavitation over a submerged hemispherical object in a wide range of cavitation numbers and the cloud cavitation around a Clark-Y hydrofoil. In particular, for the hemispherical body, we compared the surface pressure distribution with experimental data which was available in literature. Later the cloud cavitation structure and its effect on the forces of the hydrofoil were studied. The comparisons between the simulating and experimental results show that present numerical approach has good capability to predict the surface pressure coefficient and the pulsation frequency at cavitation number σ=0.4, 0.55 and 0.65 of the hemispherical body under cavitation conditions. Meanwhile, for the hydrofoil, the proposed approach is sufficiently robust to predict the characteristics of the time-averaged lift and drag coefficients and the evolution of the cloud cavity with time.