Fahad Sameer Alshammari¹, Md Fazlul Hoque², Harun-Or-Roshid², Muhammad Nadeem^3,*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.3, pp. 2197-2217, 2023, DOI:10.32604/cmes.2023.022301

Abstract We investigate the bounded travelling wave solutions of the Biswas-Arshed model (BAM) including the low group velocity dispersion and excluding the self-phase modulation. We integrate the nonlinear structure of the model to obtain bounded optical solitons which pass through the optical fibers in the non-Kerr media. The bifurcation technique of the dynamical system is used to achieve the parameter bifurcation sets and split the parameter space into various areas which correspond to different phase portraits. All bounded optical solitons and bounded periodic wave solutions are identified and derived conforming to each region of these phase portraits. We also apply the… More >

DONG HAN KIM¹, DONG RAK KWON^1,*, GI-YOUNG PARK¹, YONG SUK MOON²

BIOCELL, Vol.45, No.3, pp. 527-536, 2021, DOI:10.32604/biocell.2021.014350

Abstract This work aimed to investigate the synergetic therapeutic effects of polydeoxyribonucleotides (PDRN) combined with extracorporeal shock waves therapy (ESWT) and the effects of the therapy according to ESWT sequences on a chronic traumatic full-thickness rotator cuff tear (RCT) in rabbit models. For this purpose, thirty-two rabbits were randomly allocated into 4 groups. An excision was made to create a 5-mm sized full-thickness RCT right proximal to the insertion site on the supraspinatus. After 6 weeks, 4 different procedures (normal saline, Group 1; PDRN injection, Group 2; PDRN injection before ESWT, Group 3; PDRN injection after ESWT, Group 4) were performed.… More >

Bin Wang¹, Jing Zheng¹, Yuanyuan Yu^1,2, Runmin Lv¹, Changyue Xu^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.4, pp. 675-684, 2020, DOI:10.32604/fdmp.2020.09681

Abstract Rocket sleds belong to a category of large-scale test platforms running on the ground. The applications can be found in many fields, such as aerospace engineering, conventional weapons, and civil high-tech products. In the present work, shock-wave/rail-fasteners interaction is investigated numerically when the rocket sled is in supersonic flow conditions. Two typical rocket sled models are considered, i.e., an anti-D shaped version of the rocket sled and an axisymmetric slender-body variant. The dynamics for Mach number 2 have been simulated in the framework of a dynamic mesh method. The emerging shock waves can be categorized as head-shock, tailing-shock and reflected-shock.… More >

Tian Li^{1, *}, Xiaohan Zhang¹, Yao Jiang², Weihua Zhang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 121-130, 2020, DOI:10.32604/fdmp.2020.07976

Abstract The so-called Evacuated Tube Train (ETT) is currently being proposed as a high-speed transportation system potentially competitive with airplane transportation. Aerodynamic resistance is one of the most crucial factors for the successful design of an ETT. In the present work, a three-dimensional concept ETT model has been elaborated. The aerodynamic characteristics of the subsonic ETT have been numerically simulated under different conditions. The train’s running speed varies from 600 km/h up to 1200 km/h, and the blockage ratio is in the range between 0.1 and 0.3. As the blocking ratio and running speed increase, the resistance of the head car… More >

Souli Mhamed¹, Paul Du Bois², Essam Al-Bahkali^3,*

CMES-Computer Modeling in Engineering & Sciences, Vol.117, No.1, pp. 91-107, 2018, DOI:10.31614/cmes.2018.03888

Abstract When the simulation takes account of dissipative mechanisms, e.g. heat conduction and viscosity, the shocks become smeared out to produce thin layers of rapidly and continuously varying energy, density, pressure and velocity rather than discrete surfaces of mathematical discontinuity. In the mid twentieth century, Von Neumann and Richtmyer suggested the use of a viscous pressure term (bulk viscosity) in the equilibrium equations for ideal gases in order to examine the shock while avoiding numerical oscillations at the shock front. When the bulk viscosity is included in the conservation equations, the comprehensive physics present a continuous solution satisfying the Rankine-Hugoniot conditions.… More >

E. Krause¹, W. Schröder¹, M. Klaas¹, O. Thomer¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.1, pp. 41-46, 2008, DOI:10.3970/icces.2008.005.041

Abstract In supersonic flow the leading edge vortex of delta wings can encounter intersection by an oblique or a normal shock. The resulting interaction between the two influences the aerodynamic forces, in particular the lift, especially if vortex breakdown occurs. This problem was studied in an idealized form by assuming an isolated slender vortex being intersected by an oblique and a normal shock, respectively. The investigation was carried out in two coordinated companion studies, one using numerical solutions of the Euler and Navier-Stokes equations, and the other experimental techniques, i. e. flow visualization methods, and Laser-Doppler and particle-image velocimetry. The measurements… More >

K. Inaba¹, M. Yamamoto², J.E. Shepherd³, A. Matsuo⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.1, pp. 41-46, 2007, DOI:10.3970/icces.2007.004.041

Abstract The purpose of this research is to explore an explanation of detonation soot track formation, comparing with previous hypothesis of formation mechanism. Focusing on the role of shear stress in transporting soot along the surface, we investigated the non-reactive Mach reflections numerically with three-dimensional compressible Navier-Stokes simulations. Numerical results are compared with a two-dimensional detonation simulation and used to investigate the effect of shear stress spatial and temporal variations on soot redistributions. The motions of soot due to surface shear stress are numerically examined with treating soot as particles and fluid parcel. More >

Zhijie Huang^1,2,3, Zuyu Chen^1,2,3, Xiaodan Ren^4,*, Jing Hu³, Xuedong Zhang³, Lu Hai⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.1, pp. 139-155, 2019, DOI:10.31614/cmes.2019.04596

Abstract Damage and threats to hydraulic and submarine structures by underwater explosions (UNDEXs) have raised much attention. The centrifuge model test, compared to prototype test, is a more promising way to examine the problem while reducing cost and satisfying the similitude requirements of both Mach and Froude numbers simultaneously. This study used a systematic approach employing centrifuge model tests and numerical simulations to investigate the effects of UNDEXs on an air-backed steel plate. Nineteen methodical centrifuge tests of UNDEXs were conducted. The shock wave pressure, bubble oscillation pressure, acceleration and the strain of the air-backed steel plate were recorded and compared… More >

R. Messahel¹, M. Souli¹

CMES-Computer Modeling in Engineering & Sciences, Vol.96, No.6, pp. 435-455, 2013, DOI:10.3970/cmes.2013.096.435

Abstract Simulation of Fluid Structure Interaction FSI, problems becomes more and more the focus of computational engineering, where FEM (Finite element Methods) for structural mechanics and Finite Volume for CFD are dominant. New formulations have been developed for FSI applications using mesh free methods as SPH method, (Smooth Particle Hydrodynamic). Up to these days very little has been done to compare different methods and assess which one would be more suitable. For small deformation, FEM Lagrangian formulation can solve structure interface and material boundary accurately; the main limitation of the formulation is high mesh distortion for large deformation and moving structure.… More >

Souli, M.¹, Aquelet, N.², Al-Bahkali, E.³, Moatamedi, M.⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.91, No.2, pp. 119-133, 2013, DOI:10.3970/cmes.2013.091.119

Abstract To simulate accurately a pressure wave propagation problem, a fine mesh is required in order to capture peak pressures accurately. This may require a very large size problem with several millions of elements. To reduce CPU time and prevent high mesh distortion, a two-dimensional problem for blast ignition and pressure propagation is performed first on a fixed Eulerian mesh. When the pressure wave gets closer to the structure, a three dimensional ALE simulation follows, where the fluid mesh and structure mesh at the fluid structure interface are coincident. The three dimensional problem is performed after mapping history variables from the… More >