The Research of Calculation Method on Vertical Natural Frequency of the New Full-Prefabricated Floor

2016 ◽  
Vol 846 ◽  
pp. 506-511
Author(s):  
Chong Fang Sun ◽  
Shu Ting Liang ◽  
Xiao Jun Zhu
Keyword(s):  
Numerical Simulation ◽  
Natural Frequency ◽  
Calculation Method ◽  
Variable Stiffness ◽  
Series Method ◽  
Numerical Simulation Result ◽  
Stiffness Method ◽  
Calculation Results ◽  
New Type ◽  
Test Result

New-type floor is composed of three kinds of slabs joined together through fittings. It is a kind of anisotropic two-way slab. In order to study the calculation method of natural frequency, series method, variable thickness method and variable stiffness method are adopted to calculate the natural frequency. The calculation results of three methods are compared with test result and numerical simulation result. The conclusion is that the calculation result of the variable stiffness method is the closest to the real natural frequency of new-type floor.

scholarly journals Buried Depth of a Submarine Pipeline Based on Anchor Penetration

2019 ◽  
Vol 7 (8) ◽  
pp. 257
Author(s):  
Xueyuan Zhu ◽  
Qinglong Hao ◽  
Jie Zhang
Keyword(s):  
Numerical Simulation ◽  
Penetration Depth ◽  
Water Depth ◽  
Calculation Method ◽  
Water Surface ◽  
Submarine Pipeline ◽  
Projected Area ◽  
Actual Measurement ◽  
Calculation Results ◽  
The Relationship

Anchor penetration is an important issue involved in the study of submarine pipeline damage accidents. To explore the penetration of a ship’s anchor under certain conditions, this study investigated the motion and force of an anchor and formulated a calculation method for the bottoming speed of an anchor. Meanwhile, the depth of anchor penetration was calculated under different conditions according to bottoming speed through programming. Finally, the reliability of the calculation method for the penetration depth was verified by comparing the actual measurement and the numerical simulation. On the basis of the findings, the calculation results were further analyzed, and conclusions were derived regarding the relationship between anchor mass, the horizontal projected area of the anchor, the anchor height on the water surface, and water depth. The conclusions provide suggestions for the application of anchor penetration in terms of seabed depth with certain reference values.

Application Research on Natural Frequency Method in Single Terminal Traveling Wave Fault Location

2013 ◽  
Vol 341-342 ◽  
pp. 1393-1396
Author(s):  
Li Gao ◽  
Hong Chun Shu
Keyword(s):  
Numerical Simulation ◽  
Natural Frequency ◽  
Traveling Wave ◽  
Fault Location ◽  
Travelling Wave ◽  
Application Research ◽  
Frequency Method ◽  
Location Method ◽  
Calculation Results

A method is provided to make natural frequency method be applied to single terminal traveling wave fault location in the paper. A group of fault distance suspected is calculated by single terminal method of traveling wave fault location method firstly, then deal with current travelling wave of fault by FFT to get the natural frequency reflecting fault location so that a fault distance can be calculated by it. Contrast the fault distance from natural frequency method and everyone of the group of fault distance suspected from single terminal method of traveling wave fault location method to determine the suspected fault distance closed to it is the calculation results we want. Numerical simulation shows the method can improve effectively the reliability of single terminal traveling wave fault location.

The Modal Analysis of Roller Chain Drives

2011 ◽  
Vol 291-294 ◽  
pp. 1551-1554 ◽  
Author(s):  
Bao Lin Li ◽  
Shuai Fan ◽  
Yan Zhang
Keyword(s):  
Numerical Simulation ◽  
Theoretical Calculation ◽  
Natural Frequency ◽  
Engineering Application ◽  
Simplified Model ◽  
Harmonic Response ◽  
Roller Chain ◽  
Calculation Results ◽  
Chain Drives ◽  
Ansys Workbench

Aiming at calculating the natural frequency of roller chain drives, the software Catia was used for modeling the roller chain drives accurately and Ansys Workbench was applied to analyze the modal and harmonic response of the tension side chains, comparing the natural frequency and the theoretical calculation results of simplified model. The results showed that the deviation increased with the increase of the order of natural frequency and modal numerical simulation provides certain reference for engineering application.

scholarly journals Dynamic Behavior and Serviceability Analysis of a New Type of U-Shaped Steel-Concrete Composite Floor Slab

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Yaqin Lu ◽  
Hongkun Shang ◽  
Zhengnong Li ◽  
Kejian Ma ◽  
Lan Jiang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Natural Frequency ◽  
Experimental Test ◽  
Experimental Tests ◽  
Modal Assurance Criterion ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Calculation Results ◽  
New Type

A new type of U-shaped steel-concrete composite floor is analyzed in detail. The experimental test and finite element analysis of the floor are conducted to study the natural frequency and serviceability characteristics of the new composite floor structure. The natural frequency of the floor is measured under the environmental random vibration stimulating method, and the peak acceleration of the floor is measured under pedestrian-induced load. The experimental test results show that the U-shaped steel-concrete composite floor has better antiseismic behaviors and meet the specified serviceability requirements. The finite element analysis results indicate the constraints have a great impact on the calculation results. The experimental tests and FEM results of the floor are compared based on the modal assurance criterion, and the results are in good agreement. The experimental test acceleration curves demonstrate that the peak values meet the requirements of Chinese specification.

scholarly journals Study on elastic deformation calculation method of a composite-metal hybrid assembling stringed truss bridge

2019 ◽  
Vol 275 ◽  
pp. 02017 ◽  
Author(s):  
Zigang Zeng ◽  
Li Chen ◽  
Dong Zhao ◽  
Mao Haifeng ◽  
Zhang Dongdong ◽  
...  
Keyword(s):  
Calculation Method ◽  
Live Load ◽  
Truss Bridges ◽  
Steel Bar ◽  
Calculation Results ◽  
New Type ◽  
The Difference ◽  
Steel Sleeve ◽  
Truss Bridge ◽  
Bolt Connection

A composite-metal hybrid assembling stringed truss bridge which based on pre-tightened tooth connection can make full use of the strength of the FRP fiber in the direction of the fiber, and is of higher bearing capacity than the FRP truss bridges with traditional adhesive or bolt connection. However, whether the calculation method of FRP truss bridge with traditional bondingor bolt connection is suitable for this new type of bridge needs to be researched because of the difference on the structural form and connection mode. In order to obtain the suitable method of this kind of bridge, a new method for calculating live load deformation which consider the influence of end of the steel bar sleeve of rod stiffness was established in this paper; the deformation experiment of truss bridge was carried out. The experiment and calculation results show: compared with the calculation method of the live load deformation of the traditional FRP truss bridge, the calculation method of live load deformation considering the effect of the steel sleeve on the end of the rod is in good agreement with the live load deformation obtained by the experiment; the calculation method of inelastic deflection has also been verified by the experimental results.

scholarly journals Numerical and Experimental Study of Lightning Stroke to BIPV Modules

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 748
Author(s):  
Xiaoyan Bian ◽  
Yao Zhang ◽  
Qibin Zhou ◽  
Ting Cao ◽  
Bengang Wei
Keyword(s):  
Numerical Simulation ◽  
Experimental Study ◽  
Coupling Model ◽  
Maximum Temperature ◽  
Lightning Stroke ◽  
Study Results ◽  
Pv Modules ◽  
New Type ◽  
Metal Frame ◽  
Current Flows

Building Integrated Photovoltaic (BIPV) modules are a new type of photovoltaic (PV) modules that are widely used in distributed PV stations on the roof of buildings for power generation. Due to the high installation location, BIPV modules suffer from lightning hazard greatly. In order to evaluate the risk of lightning stroke and consequent damage to BIPV modules, the studies on the lightning attachment characteristics and the lightning energy withstand capability are conducted, respectively, based on numerical and experimental methods in this paper. In the study of lightning attachment characteristics, the numerical simulation results show that it is easier for the charges to concentrate on the upper edge of the BIPV metal frame. Therefore, the electric field strength at the upper edge is enhanced to emit upward leaders and attract the lightning downward leaders. The conclusion is verified through the long-gap discharge experiment in a high voltage lab. From the experimental study of multi-discharge in the lab, it is found that the lightning interception efficiency of the BIPV module is improved by 114% compared with the traditional PV modules. In the study of lightning energy withstand capability, a thermoelectric coupling model is established. With this model, the potential, current and temperature can be calculated in the multi-physical field numerical simulation. The results show that the maximum temperature of the metal frame increases by 16.07 °C when 100 kA lightning current flows through it and does not bring any damage to the PV modules. The numerical results have a good consistency with the experimental study results obtained from the 100 kA impulse current experiment in the lab.

Sublimation of composite ice and its influence on performance of ice shells

2021 ◽  
Vol 36 (1) ◽  
pp. 67-77
Author(s):  
Yue Wu ◽  
Junkai Huang ◽  
Jiafeng Chen
Keyword(s):  
Numerical Simulation ◽  
Shell Structure ◽  
Composite Shell ◽  
Engineering Practice ◽  
Sublimation Rate ◽  
Long Span ◽  
Static Performance ◽  
New Type ◽  
Ice Sublimation ◽  
Composite Shell Structure

The long-span ice composite shell structure is a new type of ice and snow structure developed in recent years. The engineering practice of ice composite shell shows that sublimation is one of the important reasons for its damage and even collapse. In this paper, we firstly supplemented the existing H-K equation and obtained the revised ice sublimation equation through indoor evaporative plate experiment considering the influence of admixtures and wind speed. Afterwards, combining the simulations of solar radiation and CFD, the numerical simulation of sublimation distribution on the surface of were realized by programming in Grasshopper platform. During sublimation, the thickness of the ice composite shell decreases by 0.38 mm every 10 days and the sublimation rate on the sunny side was 1.7 times that on the shady side. Finally, the static performance and stability of the sublimated ice composite spherical shell were analyzed. After 70 days of sublimation, the thickness of the ice composite shell structure becomes thinner and uneven, which leads its sensitivity to external load increases.

scholarly journals Numerical Simulation of Intrachamber Processes in the Power Plant

2021 ◽  
Vol 11 (11) ◽  
pp. 4990
Author(s):  
Boris Benderskiy ◽  
Peter Frankovský ◽  
Alena Chernova
Keyword(s):  
Numerical Simulation ◽  
Power Plant ◽  
Flow Structure ◽  
Power Plants ◽  
Control Volume ◽  
Conjugate Problem ◽  
Topological Features ◽  
Gas Dynamic ◽  
Calculation Results ◽  
Volume Method

This paper considers the issues of numerical modeling of nonstationary spatial gas dynamics in the pre-nozzle volume of the combustion chamber of a power plant with a cylindrical slot channel at the power plant of the mass supply surface. The numerical simulation for spatial objects is based on the solution conjugate problem of heat exchange by the control volume method in the open integrated platform for numerical simulation of continuum mechanics problems (openFoam). The calculation results for gas-dynamic and thermal processes in the power plant with a four-nozzle cover are presented. The analysis of gas-dynamic parameters and thermal flows near the nozzle cover, depending on the canal geometry, is given. The topological features of the flow structure and thermophysical parameters near the nozzle cap were studied. For the first time, the transformation of topological features of the flow structure in the pre-nozzle volume at changes in the mass channel’s geometry is revealed, described, and analyzed. The dependence of the Nusselt number in the central point of stagnation on the time of the power plants operation is revealed.

Numerical Simulation Study on Cooling Characteristics of a New Type of Film Hole

2020 ◽  
Author(s):  
Chunhai Guo ◽  
Bin Wang ◽  
Zhenya Kang ◽  
Wenwu Zhang ◽  
Huilong Zheng
Keyword(s):  
Numerical Simulation ◽  
Simulation Study ◽  
New Type

Numerical Simulation of Cavitating Flow in a Francis Turbine

2008 ◽  
Author(s):  
Lingjiu Zhou ◽  
Zhengwei Wang ◽  
Yongyao Luo ◽  
Guangjie Peng
Keyword(s):  
Numerical Simulation ◽  
Transport Equation ◽  
Flow Rate ◽  
Suction Side ◽  
Cavitating Flow ◽  
Francis Turbine ◽  
Efficiency Change ◽  
Experiment Data ◽  
Calculation Results ◽  
Vapor Fraction

The 3-D unsteady Reynolds averaged Navier-tokes equations based on the pseudo-homogeneous flow theory and a vapor fraction transport-equation that accounts for non-condensable gas are solved to simulate cavitating flow in a Francis turbine. The calculation results agreed with experiment data reasonably. With the decrease of the Thoma number, the cavity first appears near the centre of the hub. At this stage the flow rate and the efficiency change little. Then the cavity near the centre of the hub grows thick and the cavities also appear on the blade suction side near outlet. With further reduce of the Thoma number the cavitation extends to the whole flow path, which causes flow rate and efficiency decrease rapidly.

Sign in / Sign up

Export Citation Format

Share Document