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Wu X.Y.,Zhejiang institute of mechanical and electrical engineering Co. | Luo A.P.,Zhejiang Jianyu property management Co.
Advanced Materials Research | Year: 2014

In this paper, finite element model (FEM) of a reinforced concrete structure cantilevered slab was established in non-linear finite element software ABAQUS. Influence of cantilever length and tensile reinforcement on the structural displacement and vibration frequency was calculated. The results show that the vibration frequency of the first order and maximum displacement will various with the diameter of the reinforced cantilever slab and the length of the cantilevered slab. This paper will offer the references to the analysis and design of the cantilever slab. © (2014) Trans Tech Publications, Switzerland.


Wu X.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Luo A.,Zhejiang Jianyu Property Management Co.
Applied Mechanics and Materials | Year: 2012

The deployable structure of the ring truss have advantage properties, which can be used as an effective supporting structure of deployable antenna. The deployable experiment of ring truss antenna showed that there was asynchronous phenomenon at the course of the deployment. Dynamics theory including constraint equations and considering friction factor are built firstly. Then simulation is studied systematically for the deployment process of ring truss deployable antenna. At last, the conclusions are obtained that the friction insulted in tensile forces of the cable drive decrease and the asynchronous phenomenon in the process of the deployment. It will give some help to the design and manufacture of the ring truss antenna. © (2012) Trans Tech Publications, Switzerland.


Pan D.-J.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Li T.,Zhejiang University of Technology | Qi L.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Yu H.-C.,Zhejiang Institute of Mechanical and Electrical Engineering Co.
Zhuzao/Foundry | Year: 2011

The automatic production line of crankshaft with sand coated iron mould was analyzed in detail from aspects such as the main equipment, casting process, layout of the production line and the automatic control system. It is pointed out that the automatic production line shows the features of better applicability and broad application prospect. Meanwhile some existing problems and solution methods for the production line were discussed.


Lin Z.,Zhejiang Sci-Tech University | Lin Z.,The Zhejiang Provincial Key Laboratory of Fluid Transmission Technology | Lin Z.,Zhejiang Institute of Mechanical and Electrical Engineering co. | Ma G.,Zhejiang Sci-Tech University | And 8 more authors.
Journal of Natural Gas Science and Engineering | Year: 2016

This article is intended to elaborate different inlet velocities that respectively are 13 m/s,15 m/s and 17 m/s to influence flow resistance characteristics and the internal flow characteristics of gate valve in the medium-low pressure gas transmission. This paper presents the CFD analysis of flow resistance characteristics and the internal flow characteristics of gate valve in a gate valve with different inlet velocity. Gate valves under different inlet velocity have eight relative opening degrees that respectively are 1/8, 2/8, 3/8, 4/8, 5/8, 6/8, 7/8 and 1. For every relative opening degree of gate valve structure, the systematic CFD simulations of flow resistance, pressure fluid, velocity fluid, velocity streamline and pressure coefficient characteristics. The study mainly analyses the pressure field distribution, velocity distribution, the velocity streamline distribution when the relative opening degree is 1/8, 2/8 and 1. Experimental measurements are also conducted for flow resistance characteristics and then compared with simulated flow resistance results. The CFD simulated flow resistance results show a good agreement with that of experimental flow resistance based on the Reynolds Stress Model (RSM) turbulence model provided by fluent software. Through analysis of flow resistance properties and internal flow characteristics, we concluded that it is not stable before the relative opening degree 2/8 that the valve flow resistance characteristics and internal flow characteristics, which need to be optimized; however, the valve flow resistance characteristics and flow characteristics gradually can be gradually stabilized after the relative opening degree 2/8, and does not have the characteristics of regulating valve. In the process of gas transmission, pressure energy loss mainly occurs in the valve core. © 2016 Elsevier B.V.


Zhang Y.-L.,Zhejiang University | Zhu Z.-C.,Zhejiang University | Zhu Z.-C.,Zhejiang Sci-Tech University | Cui B.-L.,Zhejiang Sci-Tech University | And 2 more authors.
Kung Cheng Je Wu Li Hsueh Pao/Journal of Engineering Thermophysics | Year: 2012

To overcome the difficulty in implement of boundary conditions in the numerical simulation of transient flow in a centrifugal pump during stopping period, a closed-loop pipe system including the pump was built to accomplish a self-coupling computation. The results show that the decreasing course of flow rate lags behind that of rotational speed, and the head decreases more quickly. The continuous variations of flow angle or angle of attack are the root reason for the evolution of flow field in the pump during stopping period. The rotor-stator interaction makes flow rate present a slight fluctuation feature, in other words, the flow rate isn't invariable in a steady operating condition. During stopping period a considerably transient effect has been demonstrated, such an effect cannot be predicted precisely by means of a flow model based on the quasi-steady assumption so far. In conclusion, the transient characteristic of the centrifugal pump has preliminarily been revealed by using the CFD technique during stopping period, and the present method has provided a valuable reference for investigating into the transient behavior of other turbomachinery.


Pan D.-J.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | He Z.-M.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Xia X.-J.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Shen Y.-H.,Zhejiang Institute of Mechanical and Electrical Engineering Co.
Zhuzao/Foundry | Year: 2014

The casting technological characteristics of sand-faced metal mould casting in use of the wheel reductor shell production was analyzed, and the casting processing plan is determined. Through the solidification simulation software for solidification process simulation to optimize the plan, the as-cast production of wheel reductor shell is finally achieved with the use of sand-faced metal mould casting, which has achieved good economic benefits.


Zhu D.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Pan D.-J.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Shen Y.-H.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Xia X.-J.,Zhejiang Institute of Mechanical and Electrical Engineering Co.
Zhuzao/Foundry | Year: 2012

The five-way type automatic core shooting machine in the design ideas, main components, and application examples was introduced. The machine is stable in performance, achieving sand shooting and core-stripping in the same position, and then removing the core and sand feeding at the same time. The core shooting machine integrates machine, electricity and gas integration, which is controlled by PLC in the entire movement. The machine improves efficiency greatly, reduces labor intensity, and has been successfully used in the production of the axle sand core.


Li Y.,Zhejiang Sci-Tech University | Zhu Z.,Zhejiang Sci-Tech University | He W.,Hangzhou Dalu Industry Co. | He Z.,Zhejiang Institute of Mechanical and Electrical Engineering Co.
Chinese Journal of Mechanical Engineering (English Edition) | Year: 2012

The law governing the movement of particles in the centrifugal pump channel is complicated; thus, it is difficult to examine the solid-liquid two-phase turbulent flow in the pump. Consequently, the solid-liquid two-phase pump is designed based only on the unary theory. However, the obvious variety of centrifugal-pump internal flow appears because of the existence of solid phase, thus changing pump performance. Therefore, it is necessary to establish the flow characteristics of the solid-liquid two-phase pump. In the current paper, two-phase numerical simulation and centrifugal pump performance tests are carried out using different solid-particle diameters and two-phase mixture concentration conditions. Inner flow features are revealed by comparing the simulated and experimental results. The comparing results indicate that the influence of the solid-phase characteristics on centrifugal-pump performance is small when the flow rate is low, specifically when it is less than 2 m3/h. The maximum efficiency declines, and the best efficiency point tends toward the low flow-rate direction along with increasing solid-particle diameter and volume fraction, leading to reduced pump steady efficient range. The variation tendency of the pump head is basically consistent with that of the efficiency. The efficiency and head values of the two-phase mixture transportation are even larger than those of pure-water transportation under smaller particle diameter and volume fraction conditions at the low-flow-rate region. The change of the particle volume fraction has a greater effect on the pump performance than the change in the particle diameter. The experimental values are totally smaller than the simulated values. This research provides the theoretical foundation for the optimal design of centrifugal pump. © Chinese Mechanical Engineering Society and Springer-Verlag Berlin Heidelberg 2012.


Li Y.,Zhejiang Sci-Tech University | Cui Q.,Zhejiang Sci-Tech University | Zhu Z.,Zhejiang Sci-Tech University | He Z.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | Cui B.,Zhejiang Institute of Mechanical and Electrical Engineering Co.
ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011 | Year: 2011

Based on mixture model, the numerical simulation of solidliquid two-phase flow in a double channel pump (Specific speed ns = 81) was carried out. The effects of particle diameter, particle volume fraction and flow rate on solid volume concentration distribution, relative velocity distribution and abrasion characteristics were studied. The results reveal that in the impeller, more particles concentrate at the nut of the shaft end and the edge of the impeller outlet. So those regions are worn seriously. The abrasive types are sliding wear on the impeller outlet edge and impact wear on the nut respectively. In the wall of the volute, the concentrated areas of particles move round the anticlockwise direction when the mixture flow rate is larger. The reason is the mixture velocity is larger as the flow rate increases, and meanwhile the centrifugal force and gravity force are invariable. So the particles move round the impeller rotational direction consequently. In the volute, particles concentrate on the tongue and wall region, especially on the sections I, II, V and VII. So the areas are easily worn out. The abrasive type is the heavy sliding wear in the volute wall. Numerical simulation results are consistent with the actual situation. It follows that the calculating method is feasible. Copyright © 2011 by ASME.


Li Y.,Zhejiang Sci-Tech University | Zhu Z.,Zhejiang Sci-Tech University | He Z.,Zhejiang Institute of Mechanical and Electrical Engineering Co. | He W.,Hangzhou Dalu Industry Co.
Journal of Thermal Science | Year: 2011

Based on the solid-liquid two-phase mixture transportation test, the renormalization group (RNG) k-e turbulent model was utilized to simulate the solid-liquid two-phase turbulent flow in a centrifugal pump. By comparing the simulated and experimental results, inner flow features were revealed to improve the abrasion characteristic of the solid-liquid two-phase centrifugal pump. The influence of the solid phase on centrifugal pump abrasive performance is small when the particle volume fraction is less than 2.5%. The aggregation degree of the solid particles is enhanced as the particle diameter increases from 0.1 to 1 mm; however, the mixture density on the pressure side is reduced when the particle diameter increases to 1 mm for the impact of inertia. The wear on the hub is most severe for the shear stress on this position; it is also the largest. The wear characteristic is affected greatly by the parameters of the solid phase. The wear chracteristic can be optimized by decreasing the blade outlet angle. In the modified design, the blade angle is different, whereas the other geometric dimensions remain the same. The improved pump is simulated to contrast with the original pump. The results show that the values of mixture density and shear stress both decrease. The wear condition of the blade is improved to a certain extent. © 2011 Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag Berlin Heidelberg.

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