scholarly journals Simplified Algorithm Model for Explosion Shockwave Load in the Cabin

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Qing-hua Chen ◽  
Yue-qiu Jiang ◽  
Yu-xin Gao ◽  
Yu-hang Liu ◽  
Jia-qi Yang
Keyword(s):  
Numerical Modeling ◽  
Numerical Model ◽  
Damage Assessment ◽  
Central Area ◽  
Engineering Model ◽  
Wall Area ◽  
Simulation Calculation ◽  
Internal Explosion ◽  
Calculation Results ◽  
Simplified Algorithm

In order to obtain the shockwave load simplified algorithm model for the semiarmored projectile internal explosion in the cabin, this research made use of AUTODYN to provide a numerical modeling method for explosion in the cabin and verified the accuracy of the method via the experiment. Internal explosion simulation calculation was conducted on the operating condition numerical model with different cabin structural dimensions and different explosive loads. The cabin internal explosion space was divided into the noncorner central area, near-wall area, two-sided corner area, and three-sided corner area. Through regression of the abovementioned calculation results, an engineering model to calculate the shockwave load was obtained. It is hoped that the model can offer some references to the antiexplosion design for the ship cabin and for damage assessment of the internal explosion.

Groundwater flow simulation and its application in GaoSong ore field, China

2018 ◽  
Vol 10 (2) ◽  
pp. 276-284 ◽  
Author(s):  
Gang Chen ◽  
Shiguang Xu ◽  
Chunxue Liu ◽  
Lei Lu ◽  
Liang Guo
Keyword(s):  
Numerical Model ◽  
Flow Field ◽  
Groundwater Flow ◽  
Mine Water ◽  
Permeability Coefficient ◽  
Water Inrush ◽  
Seepage Field ◽  
Groundwater Seepage ◽  
Calculation Results ◽  
Groundwater Flow Field

Abstract Mine water inrush is one of the important factors threatening safe production in mines. The accurate understanding of the mine groundwater flow field can effectively reduce the hazards of mine water inrush. Numerical simulation is an important method to study the groundwater flow field. This paper numerically simulates the groundwater seepage field in the GaoSong ore field. In order to ensure the accuracy of the numerical model, the research team completed 3,724 field fissure measurements in the study area. The fracture measurement results were analyzed using the GEOFRAC method and the whole-area fracture network data were generated. On this basis, the rock mass permeability coefficient tensor of the aquifer in the study area was calculated. The tensor calculation results are used in the numerical model of groundwater flow. After calculation, the obtained numerical model can better represent the groundwater seepage field in the study area. In addition, we designed three different numerical models for calculation, mainly to explore the influence of the tensor assignment of permeability coefficient on the calculation results of water yield of the mine. The results showed that irrational fathom tensor assignment would cause a significant deviation in calculation results.

scholarly journals Geological region by multi-signal method of gravity anomaly data in central Vietnam area

2021 ◽  
Vol 62 (5) ◽  
pp. 43-54
Author(s):  
Hong Thi Phan ◽  
Petrov Aleksey Vladimirovich ◽  
Phuong Minh Do ◽  
Luu Truong Nguyen ◽  
Keyword(s):  
Central Area ◽  
Tectonic Activity ◽  
Horizontal Gradient ◽  
Spectral Correlation ◽  
Sliding Windows ◽  
The North ◽  
Central Vietnam ◽  
Two Dimensional Filtering ◽  
Calculation Results ◽  
Signal Method

This paper presents the research results of applying the combined method of probabilistic statistical approaches, energy density spectral correlation, two-dimensional filtering in dynamic sliding windows, full horizontal gradient and heterogeneous axis tracking method to process and interpret the Bughe gravitational anomaly field in central area Vietnam. The calculation results have shown the superiority of the twodimensional filter in dynamic sliding windows compared to the filters in fixed windows in GEOSOFT software, GMT software. According to the physical characteristics of the field, the study area was divided into 13 homogeneous classes, this result is consistent with the geological-tectonic data in the area. In the north and northeast, the stabilized rock layers are characterized by homogeneous layers that extend in the northwestsoutheast direction. In the south and southwest, there is complex tectonic activity characterized by high density rock layers overlain by low density rock layers in each fault band with different directions of development. This suggests that there may be deeply buried mineral deposits of magmatic origin in central area Vietnam.

NUMERICAL SIMULATION OF THE LIGHT AIRCRAFT PROPELLER NOISE UNDER STATIC CONDITION

Akustika ◽  
2021 ◽  
pp. 100-106
Author(s):  
sergey Timushev ◽  
Alexey Yakovlev ◽  
Petr Moshkov
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Numerical Modeling ◽  
Vortex Method ◽  
Static Condition ◽  
Semiempirical Model ◽  
Calculation Methods ◽  
Propeller Noise ◽  
Calculation Results ◽  
Static Conditions

The problem of simulation the noise generated during the operation of the propeller is considered. Calculation methods are described and numerical simulation of the noise of a light aircraft propeller by the acoustic-vortex method is performed. The results of numerical modeling of the tonal components of the propeller noise when operating under static conditions are compared with experimental data and calculation results based on a semiempirical model.

scholarly journals Dating the Irrigation System of the Samarkand Oasis: A Geoarchaeological Study

Radiocarbon ◽  
2012 ◽  
Vol 54 (1) ◽  
pp. 91-105 ◽  
Author(s):  
Luca C Malatesta ◽  
Sébastien Castelltort ◽  
Simone Mantellini ◽  
Vincenzo Picotti ◽  
Irka Hajdas ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Numerical Model ◽  
Radiocarbon Dating ◽  
Overland Flow ◽  
Irrigation System ◽  
Archaeological Sites ◽  
New Approach ◽  
Sedimentary Deposits ◽  
New Evidence ◽  
Southern Flank

The oasis of Samarkand in the Middle Zeravshan Valley (modern Uzbekistan) was a major political and economic center in ancient western Central Asia. The chronology of its irrigation system was, until now, only constrained by the quality and quantity of archaeological findings and several different hypotheses have been proposed for it. We use a new approach combining archaeological surveying, radiocarbon dating, sedimentary analysis, and the numerical modeling of a flood event to offer new evidence for, and quantitative dating of, the development of irrigation system on the southern flank of the Middle Zeravshan Valley. We analyzed 13 bones and charcoals from 3 archaeological sites and obtained new 14C ages from Afrasiab (ancient Samarkand), a dwelling damaged by flooding in the 2nd century AD (site code: SAM-174) and the fortress of Kafir Kala. We established the origin of sedimentary deposits at the sites to infer the presence of the 2 most important canals of the southern flank: the Dargom and the Yanghiaryk. Finally, we show with a numerical model of overland flow that a natural flood was unlikely to have produced the damage observed at SAM-174. The combined results of the study indicate that the canals south of Samarkand existed, and were mainly developed, in the 2nd century AD and were not connected to the main feeding canal of Afrasiab at that time.

scholarly journals Field surveys and numerical modeling of the August 2016 Typhoon Lionrock along the northeastern coast of Japan: the first typhoon making landfall in Tohoku region

2020 ◽  
Vol 105 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Mohammad Heidarzadeh ◽  
Takumu Iwamoto ◽  
Tomohiro Takagawa ◽  
Hiroshi Takagi
Keyword(s):  
Numerical Modeling ◽  
Numerical Model ◽  
Tide Gauge ◽  
Wave Runup ◽  
Field Surveys ◽  
Death Toll ◽  
Hurricane Wind ◽  
Northeastern Japan ◽  
Strong Winds ◽  
Severe Flooding

AbstractTyphoon Lionrock, also known as the national number 1610 in Japan, caused severe flooding in east Japan in August 28–31, 2016, leaving a death toll of 22. With a maximum sustained wind speed of ~ 220 km/h from the Joint Typhoon Warning Center’s best track, Lionrock was classified as a category 4 hurricane in Saffir–Simpson Hurricane Wind Scale and as a typhoon in Japan Meteorological Agency’s scale. Lionrock was among unique typhoons as it started its landfall from north of Japan. Here, we studied the characteristics of this typhoon through tide gauge data analysis, field surveys and numerical modeling. Tide gauge analysis showed that the surges generated by Lionrock were in the ranges of 15–55 cm with surge duration of 0.8–3.1 days. Our field surveys revealed that the damage to coastal communities/structures was moderate although it caused severe flooding inland. We measured a maximum coastal wave runup of 4.3 m in Iwaisaki. Such a runup was smaller than that generated by other category 4 typhoons hitting Japan in the past. Our numerical model was able to reproduce the storm surge generated by the 2016 Typhoon Lionrock. This validated numerical model can be used in the future for typhoon-hazard studies along the coast of northeastern Japan. Despite relatively small surge/wave runups in coastal areas, Lionrock’s death toll was more than that of some other category 4 typhoons. We attribute this to various primary (e.g., flooding, surges, waves, strong winds) and secondary (e.g., landslides, coastal erosions, debris flows, wind-blown debris) mechanisms and their combinations and interactions that contribute to damage/death during a typhoon event.

The Research on Traction Simulation for a New Hybrid Power Train

2013 ◽  
Vol 300-301 ◽  
pp. 327-332
Author(s):  
Guo Liang Wang ◽  
Ji Ye Zhang ◽  
Xiao Hui Xu ◽  
Ming Li
Keyword(s):  
Power System ◽  
Strong Support ◽  
Power Train ◽  
Hybrid Power System ◽  
Design And Optimization ◽  
Hybrid Power ◽  
Coupling Relationship ◽  
Simulation Calculation ◽  
Train Operation ◽  
Calculation Results

A new hybrid power system with the “power grid-battery-ultracapacitor” was presented. The coupling relationship between the new hybrid power system and train driving was studied on the basis of considering the coupling relationship between train dynamics and the new hybrid power system. A traction simulation system was established. It could be used for traction simulation calculation on hybrid power train. It provided support for dynamics analysis of the new hybrid power train, design and optimization of the new hybrid power system and optimization of the train operation. In the end, traction simulation calculation for hybrid power train was done with actual line. The calculation results provided strong support for the development of the hybrid power train.

2-D AUTOMATIC COMPOSITION OF NODAL VALUES FROM NUMERICAL MODEL USING SCRIPT PROGRAMMING

2013 ◽  
Vol 62 (1) ◽  
Author(s):  
Rudi Heriansyah
Keyword(s):  
Finite Element ◽  
Numerical Modeling ◽  
Numerical Model ◽  
Finite Difference ◽  
Two Dimensional ◽  
Commercial Software ◽  
One Dimensional ◽  
Automatic Composition ◽  
The Individual ◽  
Individual Nodes

There are many commercial software to perform numerical modeling based on finite element (FEM) and finite difference (FDM) methods. It is often a requirement to the designer, that the values of the individual nodes in the numerical model are known. Usually, these softwares provide two methods to achieve this; firstly, by clicking directly onto the nodes of interest and secondly, by saving or exporting the whole nodal values to an external file. The former way is appropriate for models with small number of nodes, but as the number of nodes increases, it is no longer an efficient or effective way. Through the latter method, all nodal values are obtained, however the values are one-dimensional, and in some cases, only certain nodal values are required for presentation. In this paper, an algorithm for automatic composition of nodal values obtained from the second method mentioned above. The composed nodal values will be in two-dimensional form as this is the format used for uniform shaped model (square or rectangular). Since numerical softwares usually have facilities to save the data in a spreadsheet format, the proposed algorithm is implemented in this environment by using spreadsheet script programming.

Numerical Modeling of a Nonlinear MEMS Membrane

2004 ◽  
Author(s):  
Owen I. Crabtree ◽  
Sinisa Dj. Mesarovic ◽  
Ismail Demir ◽  
Robert F. Richards ◽  
David F. Bahr ◽  
...  
Keyword(s):  
Residual Stress ◽  
Numerical Modeling ◽  
Numerical Model ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Empirical Data ◽  
Geometrically Nonlinear ◽  
Mems Device ◽  
The Finite Difference Method ◽  
Stress Layer

A numerical model is developed to understand the behavior of a laminated, piezoelectric, geometrically nonlinear MEMS device. The finite difference method is chosen, along with the Newmark technique to model the static and vibrational behavior. This technique is validated by comparison to empirical data. The developed model is exercised to understand and optimize the device by studying residual stress, layer thicknesses, and electrode sizes with the goal of reduction of fundamental frequency and increase of charge output.

Experimental and Numerical Investigation of Dynamic Impact on Universal Breakaway Steel Post

2019 ◽  
Author(s):  
Javad Mehrmashhadi ◽  
Mojdeh A. Pajouh ◽  
John D. Reid
Keyword(s):  
Experimental Data ◽  
Numerical Modeling ◽  
Numerical Model ◽  
Dynamic Impact ◽  
Roadside Safety ◽  
Impact Performance ◽  
Component Testing ◽  
Long Span ◽  
Finite Element Package ◽  
The Impact

Abstract A closed guardrail system, known as “bullnose” guardrail system, was previously developed to prevent out-of-control vehicles from falling into the elephant trap. The bullnose guardrail system originally used Controlled Release Terminal (CRT) wood posts to aid in the energy absorption of the system. However, the use of CRT had several drawbacks such as grading and the need for regular inspections. Universal Breakaway Steel Post (UBSP) was then developed by the researchers at Midwest Roadside Safety Facility as a surrogate for CRT. In this study, the impact performance of UBSP on the weak-axis and strong-axis was studied through numerical modeling and component testing (bogie testing). A numerical model was developed using an advanced finite element package LS-DYNA to simulate the impact on UBSP. The numerical results were compared to experimental data. Further research on soil models was recommended. The numerical model will be used to investigate other applications for UBSP such as the Midwest Guardrail System (MGS) long span system, guardrail end terminal designs, or crash cushions.

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