1407 A Study of Impact Pressure by Particle Method for Dam Breaking

The moving particle semi-implicit method is a meshless particle method for incompressible fluid and has proven useful in a wide variety of engineering applications of free-surface flows. Despite its wide applicability, the moving particle semi-implicit method has the defects of spurious unphysical pressure oscillation. Three various divergence approximation formulas, including basic divergence approximation formula, difference divergence approximation formula, and symmetric divergence approximation formula are proposed in this paper. The proposed three divergence approximation formulas are then applied for discretization of source term in pressure Poisson equation. Two numerical tests, including hydrostatic pressure problem and dam-breaking problem, are carried out to assess the performance of different formulas in enhancing and stabilizing the pressure calculation. The results demonstrate that the pressure calculated by basic divergence approximation formula and difference divergence approximation formula fluctuates severely. However, application of symmetric divergence approximation formula can result in a more accurate and stabilized pressure.

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Application Research of an Efficient and Stable Boundary Processing Method for the SPH Method

Water ◽

10.3390/w11051110 ◽

2019 ◽

Vol 11 (5) ◽

pp. 1110 ◽

Cited By ~ 1

Author(s):

Xing Huang ◽

Wu Chen ◽

Zhe Hu ◽

Xing Zheng ◽

Shanqin Jin ◽

...

Keyword(s):

Interpolation Method ◽

Particle Method ◽

Processing Method ◽

Sph Method ◽

Ghost Particle ◽

Stable Boundary ◽

Research Fields ◽

Particle Hydrodynamics ◽

Improvement Effect ◽

Dam Breaking

The boundary truncation of the kernel function affects the numerical accuracy and calculation stability of the smooth particle hydrodynamics (SPH) method and has been one of the key research fields for this method. In this paper, an efficient and stable boundary processing method for the SPH method was introduced by adopting an improved boundary interpolation method (i.e., the improved Shepard method) which needs only the sum of direct accumulation for fixed-boundary particles to improve the numerical stability and computational efficiency of the fixed ghost particle method. The improvement effect of the method was demonstrated by comparing it with different interpolation methods using the cases of still water, a wave generated by dam-breaking, and a solitary wave attacking problem with fixed walls and a moveable wall. The results showed that the new boundary processing method for SPH can help remarkably improve the efficiency of calculation and reduce the oscillations of pressure when simulating various flows.

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ESTIMATION OF TSUNAMI WAVE IMPACT PRESSURE ON RIVER STRUCTURES BY AN IMPROVED PARTICLE METHOD

Journal of Japan Society of Civil Engineers Ser A1 (Structural Engineering & Earthquake Engineering (SE/EE)) ◽

10.2208/jscejseee.70.i_605 ◽

2014 ◽

Vol 70 (4) ◽

pp. I_605-I_615

Author(s):

Takaaki ABE ◽

Yoshishige SATOH ◽

Yasuhiro YOSHIKAWA ◽

Akashi ITOH ◽

Toshiyuki Ootsuki ◽

...

Keyword(s):

Tsunami Wave ◽

Particle Method ◽

Impact Pressure ◽

Wave Impact

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Numerical Investigation of Shallow Liquid Sloshing in a Baffled Tank and the Associated Damping Effect by BM-MPS Method

Journal of Marine Science and Engineering ◽

10.3390/jmse9101110 ◽

2021 ◽

Vol 9 (10) ◽

pp. 1110

Author(s):

Lizhu Wang ◽

Min Xu ◽

Qian Zhang

Keyword(s):

Pressure Gradient ◽

Particle Method ◽

Liquid Sloshing ◽

Impact Pressure ◽

Rotational Excitation ◽

Damping Effect ◽

Static Water ◽

Background Mesh ◽

Vertical Baffle ◽

Reasonable Use

Understanding the damping mechanism of baffles is helpful to make more reasonable use of them in suppressing liquid sloshing. In this study, the damping effect and mechanism of vertical baffles in shallow liquid sloshing under a rotational excitation are investigated by an improved particle method. By incorporation of a background mesh scheme and a modified pressure gradient model, the accuracy of impact pressure during sloshing is significantly enhanced. Combined with the advantages of the particle method, the present numerical method is a wonderful tool for the investigation of liquid sloshing issues. Through the analysis of impact pressure, the influences of baffle height and baffle position on the damping mechanism are discussed. The results show that the damping effect of vertical baffles increases with the increase of the elevation of baffle top and decreases with the increase of the elevation of the baffle bottom. Moreover, the resonance characteristics of sloshing are altered when static water is divided into two parts by the vertical baffle. The dominant damping mechanism of vertical baffles depends on the configurations.

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