Insight into ozone profile climatology over northeast China from aircraft measurement and numerical simulation

2021 ◽  
Vol 785 ◽  
pp. 147308
Author(s):  
Hongyue Wang ◽  
Ke Ding ◽  
Xin Huang ◽  
Wuke Wang ◽  
Aijun Ding
Keyword(s):  
Numerical Simulation ◽  
Northeast China ◽  
Aircraft Measurement ◽  
Ozone Profile ◽  
Insight Into

The Influence of Measured Trajectory Based Model Parameters Correcting on Simulation Precision of Power System Dynamic Frequency

2013 ◽  
Vol 448-453 ◽  
pp. 2545-2550
Author(s):  
Gang Mu ◽  
Ming Li ◽  
Jun An ◽  
Xing Wei Xu ◽  
Shuai Shao
Keyword(s):  
Numerical Simulation ◽  
Simulation Model ◽  
Process Simulation ◽  
Northeast China ◽  
Operation Mode ◽  
Measured Data ◽  
Model Parameters ◽  
Conservative Operation ◽  
Generator Frequency ◽  
Dynamic Frequency

Although numerical simulation is an important method of researching dynamic frequency process, obvious deviations have been found between numerical simulation and the measured trajectory in many accidents. And the existing simulation model and parameters cannot describe the actual dynamic process of frequency accurately. Research was carried out on the influence of four parameters to the dynamic frequency process, which based on the WSCC system. The four parameters include the inertia constant of generator, generator frequency coefficient, dead band and turbine intermediate superheating coefficient. Northeast China power grid and measured data are used to verify the above research conclusion. Checking the dynamic frequency process simulation model and parameters can improve the accuracy of dynamic frequency process simulation on the base of the measured trajectory and the physical characteristics of the parameters. It can also give efficient foundation for the setting work of UFLS, overcoming the previous conservative operation mode and so on.

Numerical Simulation of Damage to a Soil Embankment from Tsunami Overflow

2009 ◽  
Vol 4 (6) ◽  
pp. 469-478 ◽  
Author(s):  
Hiroyuki Fujii ◽  
◽  
Shintaro Hotta ◽  
Nobuo Shuto ◽  
Keyword(s):  
Numerical Simulation ◽  
Field Data ◽  
Erosion Rate ◽  
Fixed Bed ◽  
Present Situation ◽  
Short Wave ◽  
Water Flows ◽  
The Past ◽  
Downstream Slope ◽  
Insight Into

There have been many studies on tsunami forces acting on structures, but few studies on tsunami-induced water flows that move a lot of sands or soils, resulting in damages to such structures as road embankments and seawalls. In the present study, the damage of soil embankments by tsunami overflow is discussed. Hydraulic experiments on movable beds reveal that the erosion of the downstream slope and the scouring at the rear toe are important factors in the erosion of soil embankments. An erosion rate law is experimentally established. Current velocity measured on a fixed bed verifies the application of the CADMAS-SURF to the present situation. A numerical method to simulate the erosion of soil embankments is developed using these data. It is applied to gain insight into the Shuto diagram (2001) about the damages of embankment obtained from field data for local tsunamis of short wave period in the past. Among six tests, reasonable agreements were obtained in four cases. In other two cases, the method gave the larger erosion than the expected ones from the diagram.

Insight into fundamental aspects of the EDM process using multidischarge numerical simulation

2010 ◽  
Vol 52 (1-4) ◽  
pp. 195-206 ◽  
Author(s):  
Borja Izquierdo ◽  
José Antonio Sánchez ◽  
Naiara Ortega ◽  
Soraya Plaza ◽  
Iñigo Pombo
Keyword(s):  
Numerical Simulation ◽  
Edm Process ◽  
Insight Into

Fracture Toughness of Northeast China Larch

2012 ◽  
Vol 517 ◽  
pp. 661-668 ◽  
Author(s):  
L.P. Qiu ◽  
En Chun Zhu ◽  
Hua Zhang Zhou ◽  
L.Y. Liu
Keyword(s):  
Numerical Simulation ◽  
Fracture Toughness ◽  
Stress Intensity ◽  
Crack Propagation ◽  
Material Properties ◽  
Northeast China ◽  
Numerical Approach ◽  
Mode I ◽  
Mode Ii ◽  
Full Size

Wood, as a green and environment-friendly building material, is widely used in building engineering. Naturally grown, wood has various defects like knots, cracks and inclined grain. Fracture Mechanics is thus an efficient tool to investigate the mechanical behavior of wood and wood-based composite products. According to Linear-elastic Fracture Mechanics (LEFM), fracture toughness can be introduced to measure the resistance to crack propagation. Crack was assumed to occur when the stress intensity factorKreached a critical valueKC.Fracture in wood usually involves not only the Mode I type (open) fracture, but also the Mode II type (shear) fracture. For getting a better understanding of the crack growth phenomenon of Northeast China Larch, it is, therefore, essential to assess theKICandKIIC, which are the critical stress intensity factors for Mode I and Mode II type fracture, respectively. In the current study,KICandKIIC, of Northeast China Larch were determined through tests with compact tension specimens and tests with compact symmetric shear specimens, respectively. In addition, the material properties tests were also performed. All of the specimens were cut from the same batch of Glulam beams. Based on the obtained data from experiments, LEFM was employed to explain the fracture failure in the form of crack propagation. Using Extended Finite Element Method (XFEM), simulation of the crack propagation in Mode I and Mode II was performed incorporating ABAQUS. The crack propagation and the load-displacement curves of numerical simulation were in good agreement with experiments, which validated that the proposed numerical approach is suitable for analysis of crack growth in the specimens. As part of a larger program to investigate the fracture behavior of Glulam beams made of Northeast China Larch, this study provides the material properties and validation of the numerical simulation approach. A series of experiments of full-size curved Glulam beams subject to bending and the corresponding simulations extending the numerical approach of this study to the cases of full-size wood composite members are under development.

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