Bufan Chu^1,2, Qiwen Liu^1,2, Lisheng Liu^1,2,3,*, Xin Lai^1,2, Hai Mei^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 151-178, 2020, DOI:10.32604/cmes.2020.010115

Abstract In this study, a new bond-based peridynamic model is proposed to describe the dynamic properties of ceramics under impact loading. Ceramic materials show pseudo-plastic behavior under certain compressive loadings with high strain-rate, while the characteristic brittleness of the material dominates when it is subjected to tensile loading. In this model, brittle response under tension, softening plasticity under compression and strain-rate effect of ceramics are considered, which makes it possible to accurately capture the overall dynamic process of ceramics. This enables the investigation of the fracture mechanism for ceramic materials, during ballistic impact, in more detail. Furthermore, a bond-force updating algorithm… More >

Ivan V. Kazachkov^1,2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.5, pp. 491-507, 2019, DOI:10.32604/fdmp.2019.06477

Abstract Non-classical subjects relating to the dynamics of jet and film flow and related heat transfer processes are considered. These problems, which are relevant to several technological applications, cannot completely be addressed in the frame of the canonical Navier-Stokes equations. The first example deals with the formation of a film flow as a result of the hydraulic shock of a vertical jet impinging on a horizontal plane. The effective thickness of the film resulting from the hydraulic shock is much less than the value obtained using the conventional approach (relying on the assumption of smooth flow), while the corresponding speed is… More >

Montemayor Trejo^1,* José Alfredo, Alejandro Zermeño González², Jesús Olague Ramirez¹, Rogelio Aldaco Nuncio¹, Manuel Fortis Hernández¹, Enrique Salazar Sosa^1,3, José Cruz Rodríguez Rios¹, Cirilo Vázquez-Vázquez³

Phyton-International Journal of Experimental Botany, Vol.75, pp. 47-53, 2006, DOI:10.32604/phyton.2006.75.047

Abstract The objective of this study was to analyze the effect of different population densities and corn foliage structure in the penetration of photosynthetically active radiation, and its relationship to some yield parameters. The work was developed in the spring-summer cycle 2000 at the Ranch Hill Water, located in the kilometer 154 in the highway Saltillo – Matehuala. The Prime Time maize hybrid was established in a 3x2 factorial arrengement under a completely randomized block design and three replications. Two factors were studied: as factor a, three population densities (5.5, 7.4 and 11.1 plants m^-2), and as factor b, different foliage… More >

A. Rama Ch,ra Murthy¹, G.S. Palani¹, Nagesh R. Iyer¹

Structural Durability & Health Monitoring, Vol.4, No.4, pp. 221-230, 2008, DOI:10.3970/sdhm.2008.004.221

Abstract Empirical formulae based on experimental data to evaluate concrete penetration depth under impact loading are often used due to the complexity of the phenomena. Several design codes employ empirical formulae for the design of protective barriers. This paper presents the details of relative assessment of the use of well known empirical formulae for evaluation of concrete penetration depth under impact loading. The empirical formulae employed in the present studies include Conwep, Army corps, Haldar, Ammann and Whitney, UKAEA, BRL, Modified Petry and modified NDRC. Appropriate expressions and limitations for these empirical formulae have been provided. Performance of these empirical formulae… More >

Yanxu Guo¹, Peng Zhao², Qingsong Zhang¹, Rentai Liu^1,*, Lianzhen Zhang³, Yankai Liu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.4, pp. 321-342, 2019, DOI:10.32604/fdmp.2019.07844

Abstract To study the penetration mechanism of cement-based slurry in intersected fractures during grouting and the related pressure distribution, we have used two different variants of cement, namely, basic cement slurry and fast-setting cement slurry. The influence of a retarder, time-varying viscosity, fracture width and location of injection hole is also considered. A finite element software is used to implement two and three-dimensional numerical models for grouting of intersected fractures in hydrostatic conditions. Results show that there are significant differences in the diffusion morphology and pressure distribution depending on the considered cement slurry. Retarder can effectively slow down the rising rate… More >

Zhifan Zhang^*, Haoliang Hu, Cheng Wang^*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.3, pp. 46-46, 2019, DOI:10.32604/icces.2019.06145

Abstract A metal jet can be formed for a shaped charge subjected to air blast, which can cause local damage on structures. As for the high-velocity jet associated with underwater explosion, a high-pressure shock wave and a long-term bubble can be also generated. Underwater structures can be severely damaged by these three loadings. A Smooth Particle Hydrodynamic (SPH) method has advantages of solving problems of large deformations thanks to its mesh-free Lagrange formulation. Therefore, it is applied to simulate an entire process of a metal-jet penetration into underwater structures. First, a verification of near-field underwater explosion was carried out. The obtained… More >

Hisashi Serizawa¹, Shingo Sato², Fumikazu Miyasaka²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.1, pp. 14-14, 2019, DOI:10.32604/icces.2019.05606

Abstract It is important to predict the penetration shape of welded joints because the penetration shape strongly affects the strength of joints. As one of the methods for simulating gas metal arc welding (GMAW) process, a three-dimensional, non-stationary thermal model has been developed. By using a finite differential model based on the heat flow equation and taking account of the balance of gravity, surface tension and arc pressure, both molten pool and the penetration shape are successively demonstrated. Although the finger type penetration which is generally observed in metal insert gas (MIG) welding of aluminum alloy can reproduced by developing an… More >

D. A. Hu^1,2,3, C. Liang¹, X. Han¹, Y. Z. Chen⁴, W. F. Xu⁴

CMC-Computers, Materials & Continua, Vol.29, No.2, pp. 155-168, 2012, DOI:10.3970/cmc.2012.029.155

Abstract Penetration process of concrete plate is simulated by 3D FE-SPH adaptive coupling algorithm, which is based on experimental research of projectile with 25mm diameter penetrates concrete target. In experiment, a high speed camera is used to record dynamic deformation process of concrete plate. Acceleration responses of concrete are obtained by acceleration sensor, which is pre-embedded in target plate. This experiment is also simulated by 3D FE-SPH adaptive coupling algorithm to verify the numerical model. Numerical model is approximated initially by FEM, and distorted elements are automatically converted into meshless particles to simulate damage, splash of concrete by SPH method, when… More >

Ehsan Hedayati¹, Mohammad Vahedi²

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.3, pp. 295-323, 2017, DOI:10.3970/cmes.2017.113.307

Abstract Radius of ceramic cone can largely contribute into final solution of analytic models of penetration into ceramic/metal targets. In the present research, a modified model based on radius of ceramic cone was presented for ceramic/aluminum targets. In order to investigate and evaluate accuracy of the presented analytic model, obtained results were compared against the results of the Florence’s analytic model and also against numerical modeling results. The phenomenon of impact onto ceramic/aluminum composites were modeled using smoothed particle hydrodynamics (SPH) implemented utilizing ABAQUS Software. Results indicated that, with increasing initial velocity and ceramic thickness and decreasing support layer thickness, the… More >

Hui Zhang¹, Deli Gao^1,2, Xiaopin Xie¹

CMES-Computer Modeling in Engineering & Sciences, Vol.90, No.1, pp. 47-64, 2013, DOI:10.3970/cmes.2013.090.047

Abstract In oil & gas drilling engineering, the rock breaking efficiency as well as the trajectory of the Well should be quantitatively and accurately described by an ideal triaxial Rate of Penetration (ROP) model, taking into account the various objective and subjective factors. However, with the existing triaxial ROP models, it is difficult to achieve these goals. The applications of the existing ROP models are limited, especially in under-balanced drilling (air drilling, foam drilling etc.), because the unloading effect (i.e. the effect of the bottom hole differential pressure on the formation force) has been rarely considered. On the basis of a… More >