scholarly journals Research on Response Characteristics of Hydraulic Gate Subjected to Non-contact Underwater Explosion Load

2020 ◽  
Vol 1634 ◽  
pp. 012148
Author(s):  
Zhuoyi Yang ◽  
Xingquan Sun ◽  
Lei Song ◽  
Hui Wang ◽  
Fulin Yu
Keyword(s):  
Underwater Explosion ◽  
Response Characteristics ◽  
Explosion Load

The influence of strain rate on the cavitation time and deformation of an underwater impulsively rectangular plate

2021 ◽  
pp. 030932472110208
Author(s):  
Habib Ramezannejad Azarboni ◽  
Abolfazl Darvizeh
Keyword(s):  
Constitutive Equation ◽  
Strain Rate ◽  
Rectangular Plate ◽  
Total Pressure ◽  
Elastoplastic Deformation ◽  
Underwater Explosion ◽  
Strain Rate Effect ◽  
Linear Solution ◽  
Explosion Load ◽  
Explosive Forming

The effect of strain rate on the cavitation time and elastoplastic deformation of steel rectangular plate subjected to underwater explosion load is analytically and numerically investigated in this study. At the cavitation time, the total pressure of the explosion is eliminated so that the cavitation time plays a significant role in the elastoplastic deformation of underwater explosive forming of plate. Taking into account the strain rate effect, the Cowper-Symond constitutive equation of mild steel is employed. Exact linear solution using the Eigen function and numerical linear and nonlinear solution using finite difference method (FDM) of dynamic response of impulsively plate is obtained. Implementing the linear work hardening, the stress, strain, displacement, and velocity in any steps of loading are calculated. The time of cavitation can be recognized in elastic or plastic regimes by applying the Cowper-Symond constitutive equation. Considering the strain rate influence, the effects of charge mass and standoff are investigated to occur of cavitation and time dependent deflection and velocity of a rectangular plate.

Wall effect of underwater explosion load based on wave motion theories

2014 ◽  
Vol 28 (5) ◽  
pp. 587-598 ◽  
Author(s):  
Wei Xiao ◽  
Xiong-liang Yao ◽  
Jun Guo
Keyword(s):  
Wave Motion ◽  
Underwater Explosion ◽  
Wall Effect ◽  
Explosion Load

Investigation of the Effect of the Deck Simulator on the Shock Spectrum of Floating Shock Platform

2016 ◽  
Author(s):  
Yao Xiongliang ◽  
Cui Xiongwei ◽  
Wang Jun ◽  
Zhang Wenqi
Keyword(s):  
Underwater Explosion ◽  
Structural Difference ◽  
Body Motion ◽  
Structural Form ◽  
The Real ◽  
Assessment Tests ◽  
Shock Environment ◽  
Explosion Load ◽  
The Impact ◽  
Is Design

The investigation of the effect of the deck simulator on the shock spectrum of floating shock platform is conducted in this paper. Generally, the impact assessment tests of large-medium sized shipboard equipment are conducted on the floating shock platform. The structural form of the floating shock platform is similar to the barge’s structural form, with a strong double bottom which can ensure the safety of the bottom structure under the underwater explosion load. The tested equipment is fixed on the inner bottom plating as same as it is fixed on the real ship. It is obvious that there is a huge structural difference between floating shock platform and the real ship. The response of the real ship under explosion load is flexible-body motion, while the main response of the floating shock platform is rigid-body motion[1]. The deck can be regarded as a filter acting on the shock environment which can cause difference between the shock environments of ship and floating shock platform[2]. To decrease the shock environment difference, a special deck which is called deck simulator here is design. Through the numerical simulation and analysis, the FSP with a deck simulator can decrease the shock environment difference and can be used to test equipment with special mounting frequency demand. These conclusions have a certain guiding significance for the assessment of ship equipment in engineering applications.

The Effect of Roundness on the Buckling Strength for the Submerged Pressure Hull

2014 ◽  
Vol 644-650 ◽  
pp. 5133-5137
Author(s):  
Ching Yu Hsu ◽  
Cho Chung Liang ◽  
Tso Liang Teng ◽  
Chia Wei Chang
Keyword(s):  
Underwater Explosion ◽  
Cylinder Pressure ◽  
Pressure Loading ◽  
Finite Element Program ◽  
Buckling Strength ◽  
Element Program ◽  
Analysis Models ◽  
Explosion Load ◽  
Very High ◽  
Design Pressure

The pressure hull is the most important part of resisting pressure structures of the structural systems. The submerged pressure hull is subjected to very high hydrostatic pressure or underwater explosion load, which creates large compressive stress resultants. Due to this the pressure hull is susceptible to buckling. Buckling phenomena analysis is of greater importance in the design of the submerged pressure hulls. For the pressure hulls with local out-of-roundness, the operating depth will be greatly influenced and thus decreasing capability to resist pressure loading. Thus, this work employs the ABAQUS finite element program to analyze the effect of roundness on the buckling strength for the cylinder pressure hull. Sex kinds of out-of-roundness rateφ, 0%, 1%, 3%, 5%, 10% and 15%, were studied in this study. The bulking depth and collapse depth for the cylinder pressure hull with different out-of-roundness rate were calculated. The Analysis models and results of this study contribute to efforts to design pressure hull structures.

scholarly journals Effect of Computational Parameters on Output Properties of Underwater Explosion by Intelligent Numerical Simulation

2021 ◽  
Vol 2083 (3) ◽  
pp. 032086
Author(s):  
Yonghui Zheng ◽  
Jifeng Wei ◽  
Rui Xiao
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
Near Field ◽  
Great Influence ◽  
Underwater Explosion ◽  
Propagation Distance ◽  
Rigid Boundary ◽  
Simple Method ◽  
Mesh Density ◽  
Explosion Load

Abstract The computational parameters are of great influence on underwater explosion load. A one-dimensional wedge model is established to analyze the influence of boundary condition (BC), water domain and mesh density on the numerical simulation results. The results show that flowout BC is rigid boundary and transmit BC is not suitable for simulating the collapses phase of bubble pulsation. According to propagation distance of shock wave and its reflected wave, a simple method to calculate appropriate water domain is proposed. A positive correlation between mesh density (λ) and calculated peak pressure of shock wave (P m) is found. When λ tends to infinity, simulated Pm in near field is quite reliable, but the values in relatively far field are lower than empirical results.

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