scholarly journals Analysis on The Effect of Groyne Type Impermeable Placement on Sediment Distribution in Lariang River Bend

2021 ◽  
Vol 004 (01) ◽  
pp. 043-061
Author(s):  
Wahyu Prasetyo ◽  
Pitojo Juwono ◽  
Dian Sisinggih
Keyword(s):  
River Flow ◽  
Model Simulation ◽  
Simulation Models ◽  
Sediment Distribution ◽  
Maximum Change ◽  
Sediment Deposits ◽  
Riverbed Sediment ◽  
Simulation Results ◽  
River Bends ◽  
River Bend

Sedimentation and erosion caused by differences in discharge is a problem that often occurs at river bends. One of the functions of placing the groyne is to reduce the river flow velocity along the riverbank, accelerate sedimentation, and ensure the embankment or river bank's safety against scouring. This study aimed to determine the distribution of current velocity, distribution of riverbed shear stress, and sediment distribution to the effect of groyne placement. There are 7 (seven) simulation models used to get the most effective groyne placement. From the model simulation results by adding a groyne building on the river's outer bend for the simulation model scenario 2 to scenario 7, the largest sedimentation production is in scenario 3, namely the height of riverbed sediment deposits 230 hours of 1.094 m. Furthermore, the groyne building's effective placement is determined based on a maximum change in the riverbed scenario. In scenario 3, the placement and dimensions of the groyne length of 17.5 m; distance between groyne 24.4 m; the groyne is inclined upstream in the direction of flow 10°

scholarly journals Finding the optimum groin layout for the Konaweha river banks protection via 2D numerical modeling

2021 ◽  
Vol 930 (1) ◽  
pp. 012031
Author(s):  
J Zulfan ◽  
B M Ginting ◽  
M N Hidayat ◽  
R Rimawan
Keyword(s):  
Numerical Modeling ◽  
Flow Velocity ◽  
River Flow ◽  
Alluvial Soil ◽  
Flow Distribution ◽  
Critical Issue ◽  
River Bank ◽  
Structural Failures ◽  
River Bends ◽  
River Bend

Abstract River bank erosion has become a critical issue, especially for river bends with an alluvial soil type. Mostly, river bank erosions have caused structural failures because many national roads in Indonesia are placed near the river bend areas. Groins can reduce flow velocity, thereby increasing riverbank stability. However, most groins were installed in the river without impacting the river flow due to the improper design. This paper analyzes the use of groins placed at the river bend of the Konaweha River to protect the river bank with a length of 250 m from erosion. The evaluation employs 2D numerical modeling using MIKE21 FM to observe the influence of the groin on the river velocity, flow distribution pattern, and water level. Sixteen model scenarios with four groin configurations were tested for 25-year discharge, 2-year discharge, normal discharge 600 m3/s, and low discharge 197 m3/s to achieve the most effective plan. Based on the simulation results, Scenarios with five groins are recommended to reduce the flow velocity along the outer river bank from 2 to 0.3 m/s, thus minimizing the erosion. In addition, the spacing of groins being twice the groin length is recommended.

scholarly journals A Review of Numerical Simulations of Secondary Flows in River Bends

Water ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 884
Author(s):  
Rawaa Shaheed ◽  
Abdolmajid Mohammadian ◽  
Xiaohui Yan
Keyword(s):  
Numerical Modeling ◽  
Numerical Simulations ◽  
Secondary Flow ◽  
Cross Section ◽  
Turbulence Models ◽  
Main Flow ◽  
Secondary Flows ◽  
River Bends ◽  
River Cross Section ◽  
River Bend

River bends are one of the common elements in most natural rivers, and secondary flow is one of the most important flow features in the bends. The secondary flow is perpendicular to the main flow and has a helical path moving towards the outer bank at the upper part of the river cross-section, and towards the inner bank at the lower part of the river cross-section. The secondary flow causes a redistribution in the main flow. Accordingly, this redistribution and sediment transport by the secondary flow may lead to the formation of a typical pattern of river bend profile. It is important to study and understand the flow pattern in order to predict the profile and the position of the bend in the river. However, there are a lack of comprehensive reviews on the advances in numerical modeling of bend secondary flow in the literature. Therefore, this study comprehensively reviews the fundamentals of secondary flow, the governing equations and boundary conditions for numerical simulations, and previous numerical studies on river bend flows. Most importantly, it reviews various numerical simulation strategies and performance of various turbulence models in simulating the flow in river bends and concludes that the main problem is finding the appropriate model for each case of turbulent flow. The present review summarizes the recent advances in numerical modeling of secondary flow and points out the key challenges, which can provide useful information for future studies.

Investigation on penetration model of shaped charge jet in water

2016 ◽  
Vol 30 (02) ◽  
pp. 1550268 ◽  
Author(s):  
Jinwei Shi ◽  
Xingbai Luo ◽  
Jinming Li ◽  
Jianwei Jiang
Keyword(s):  
Numerical Simulation ◽  
Theoretical Model ◽  
Model Simulation ◽  
Theoretical Models ◽  
Theoretical Research ◽  
Water Medium ◽  
Simulation Results ◽  
Jet Penetration ◽  
The Impact ◽  
Penetration Velocity

To analyze the process of jet penetration in water medium quantitatively, the properties of jet penetration spaced target with water interlayer were studied through test and numerical simulation. Two theoretical models of jet penetration in water were proposed. The theoretical model 1 was established considering the impact of the shock wave, combined with the shock equation Rankine–Hugoniot and the virtual origin calculation method. The theoretical model 2 was obtained by fitting theoretical analysis and numerical simulation results. The effectiveness and universality of the two theoretical models were compared through the numerical simulation results. Both the models can reflect the relationship between the penetration velocity and the penetration distance in water well, and both the deviation and stability of theoretical model 1 are better than 2, the lower penetration velocity, and the larger deviation of the theoretical model 2. Therefore, the theoretical model 1 can reflect the properties of jet penetration in water effectively, and provide the reference of model simulation and theoretical research.

Hybrid Fluid Flow Simulation Combining Full Physics Simulation and Artificial Intelligence

2021 ◽  
Author(s):  
Mokhles Mezghani ◽  
Mustafa AlIbrahim ◽  
Majdi Baddourah
Keyword(s):  
Artificial Intelligence ◽  
Reservoir Simulation ◽  
History Matching ◽  
Hybrid Approach ◽  
Flow Simulation ◽  
Latin Hypercube Sampling ◽  
Simulation Models ◽  
Fine Scale ◽  
Simulation Results ◽  
Optimization Loop

Abstract Reservoir simulation is a key tool for predicting the dynamic behavior of the reservoir and optimizing its development. Fine scale CPU demanding simulation grids are necessary to improve the accuracy of the simulation results. We propose a hybrid modeling approach to minimize the weight of the full physics model by dynamically building and updating an artificial intelligence (AI) based model. The AI model can be used to quickly mimic the full physics (FP) model. The methodology that we propose consists of starting with running the FP model, an associated AI model is systematically updated using the newly performed FP runs. Once the mismatch between the two models is below a predefined cutoff the FP model is switch off and only the AI model is used. The FP model is switched on at the end of the exercise either to confirm the AI model decision and stop the study or to reject this decision (high mismatch between FP and AI model) and upgrade the AI model. The proposed workflow was applied to a synthetic reservoir model, where the objective is to match the average reservoir pressure. For this study, to better account for reservoir heterogeneity, fine scale simulation grid (approximately 50 million cells) is necessary to improve the accuracy of the reservoir simulation results. Reservoir simulation using FP model and 1024 CPUs requires approximately 14 hours. During this history matching exercise, six parameters have been selected to be part of the optimization loop. Therefore, a Latin Hypercube Sampling (LHS) using seven FP runs is used to initiate the hybrid approach and build the first AI model. During history matching, only the AI model is used. At the convergence of the optimization loop, a final FP model run is performed either to confirm the convergence for the FP model or to re iterate the same approach starting from the LHS around the converged solution. The following AI model will be updated using all the FP simulations done in the study. This approach allows the achievement of the history matching with very acceptable quality match, however with much less computational resources and CPU time. CPU intensive, multimillion-cell simulation models are commonly utilized in reservoir development. Completing a reservoir study in acceptable timeframe is a real challenge for such a situation. The development of new concepts/techniques is a real need to successfully complete a reservoir study. The hybrid approach that we are proposing is showing very promising results to handle such a challenge.

scholarly journals Eden Model Simulation of Re-Epithelialization and Angiogenesis of an Epidermal Wound

Processes ◽  
2018 ◽  
Vol 6 (11) ◽  
pp. 207
Author(s):  
Ephraim Agyingi ◽  
Luke Wakabayashi ◽  
Tamas Wiandt ◽  
Sophia Maggelakis
Keyword(s):  
Model Simulation ◽  
Cutaneous Wound Healing ◽  
Epidermal Stem Cells ◽  
Wound Edge ◽  
Wound Area ◽  
Cutaneous Wound ◽  
Simulation Results ◽  
Eden Model ◽  
And Migration ◽  
Proliferation And Migration

Among the vital processes of cutaneous wound healing are epithelialization and angiogenesis. The former leads to the successful closure of the wound while the latter ensures that nutrients are delivered to the wound region during and after healing is completed. These processes are regulated by various cytokines and growth factors that subtend their proliferation and migration into the wound region until full healing is attained. Wound epithelialization can be enhanced by the administration of epidermal stem cells (ESC) or impaired by the presence of an infection. This paper uses the Eden model of a growing cluster to independently simulate the processes of epithelialization and angiogenesis in a cutaneous wound for different geometries. Further, simulations illustrating bacterial infection are provided. Our simulation results demonstrate contraction and closure for any wound geometry due to a collective migration of epidermal cells from the wound edge in fractal form and the diffusion of capillary sprouts with the laying down of capillary blocks behind moving tips into the wound area.

Design of Control of DC Motor

2014 ◽  
Vol 611 ◽  
pp. 325-331
Author(s):  
Ľubica Miková ◽  
Michal Kelemen ◽  
Vladislav Maxim ◽  
Jaromír Jezný
Keyword(s):  
Mathematical Model ◽  
Virtual Environment ◽  
Computer Technology ◽  
Current Practice ◽  
Scientific Literature ◽  
Model Simulation ◽  
Graphical Interface ◽  
Dc Motors ◽  
Matlab Program ◽  
Simulation Results

In current practice the use of mathematical models is substantially widespread, reason being the recent increase in development of programs for this purpose, with the option of model simulation in a virtual environment, proportional to the evolving computer technology. The article contains a mathematical model created using Matlab program. The simulation results are compared with scientific literature that addresses DC motors and evaluated. For simplicity, a graphical interface was created.

Model Simulation of the Software Compatibility Testing Based on Android System

2014 ◽  
Vol 687-691 ◽  
pp. 2640-2643
Author(s):  
Xiang Gang Wang
Keyword(s):  
Model Simulation ◽  
System Simulation ◽  
Analysis Model ◽  
Compatibility Analysis ◽  
Detection Analysis ◽  
Android System ◽  
Simulation Results

in current, the software compatibility testing of Android system has been a difficulty, mainly because the software features of which has bigger difference cannot establish constrained detection analysis model. To solve this problem, a new compatibility analysis model of Android system is proposed. Android portfolio software is made compatibility testing modeling with a decomposition thought. The software features after decomposition are made repartition test modeling. The steady probability in different region combination is analyzed, and thus it represents the compatibility of Android system. Simulation results show that this kind of model can preferably complete the compatibility analysis work of Android system.

scholarly journals Studi Pengaruh Sudut Belokan Sungai Terhadap Volume Gerusan

2017 ◽  
Vol 4 (1) ◽  
pp. 60 ◽  
Author(s):  
Hasdaryatmin Djufri
Keyword(s):  
Experimental Model ◽  
Water Flow ◽  
Model Tests ◽  
Sand Layer ◽  
Flow Discharge ◽  
Layer Density ◽  
Artificial Channel ◽  
River Bends ◽  
The Stability ◽  
River Bend

Scouring occurs along the streams and generally increases in their bend areas. This occurence threaten the stability of buildings and facilities built around those areas. This study was conducted by experimental model tests in a laboratory using an artificial channel made of sand with diameter of 0,47 mm and the sand layer density of 1,47 gr/cm3. To assess the effect of river bends on the extent of scours, the water flow was simulated on the artificial channel in 9 times i.e.; 3 variations in the angle of river bends (α) and 3 variations in the flow discharge (Q) for each river bend variation. This study revealed that the volume of scours positively correlated to the angle of river bends. The volume of scours decreased more 20% when the angle of river bends decresed from 60º to 30º. The increase of the flow discharge also enlarged the volume of scours more than 100% at the river bends with small angles

Effect of Strain Rate on the Simulation of MEMS Safety and Arming Device

2014 ◽  
Vol 609-610 ◽  
pp. 849-855
Author(s):  
Wen Rui Ma ◽  
Guang He
Keyword(s):  
Finite Element Analysis ◽  
Strain Rate ◽  
Impact Load ◽  
Simulation Models ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Experimental Results ◽  
Analysis Software ◽  
Element Analysis ◽  
Simulation Results

Under launch impact load, LIGA nickel that manufacturing MEMS fuze safety and arming (S&A) device will have obvious strain rate effect. By using finite element analysis software ANSYS/LS-DYNA, simulation models of a small-caliber ammunition MEMS fuze setback S&A device with strain rate effect and without strain rate effect were respectively established. The results of the two simulation modules were quite different. Comparisons between experimental results and simulation results show that simulation results considering strain rate effect agree well with experimental results, which proves strain rate effect should not be ignored in the simulation of MEMS S&A device.

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