Analytical and numerical modeling of the transient elasto-dynamic response of a cylindrical tube to internal gaseous detonation (original) (raw)
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Analytical modeling of the elastic structural response of tubes to internal detonation loading
International Journal of Pressure Vessels and Piping, 2005
The internal detonation loading of cylindrical shells involves loads that propagate at high speeds. Since the speed of the gaseous detonation can be comparable to the flexural-wave-group speed, the excitations of flexural waves in the tube wall become significant. Flexural waves can result in high strains, which may exceed the equivalent static strains (caused by the same nominal loading pressure) by up to a factor of 4. This paper presents a new analytical model for the transient elastodynamic structural response of cylindrical shells with finite length to internal detonation loading. It is shown that, due to the consideration of the effects of transverse shear and rotary inertia, the predictions of dynamic structural response of tubes provided by this model are in better agreement with the experimental results, than existing analytical models. The model is verified through comparison with experimental results reported in the literature. q
Transient dynamic response of tubes to internal detonation loading
Journal of Sound and Vibration, 2006
This paper reports the analytical and numerical modeling of transient-dynamic response of tubes to internal detonation loading. Since gaseous detonation involves loads that propagate at high speeds, the excitations of flexural waves in the tube wall become significant. Flexural waves can result in high strains, which may exceed the equivalent static strains by up to a factor of 4. The presented analytical model, which considers the effects of transverse shear and rotary inertia, provides a very good simulation of the structural response of cylindrical tubes with finite length to internal detonation loading. It is shown that the predictions provided by this model are in better agreement with the experimental results, as compared to the existing analytical models. In the numerical part of this study, several finite element analyses are carried out to obtain the structural response of the tube to pressure loads moving at different speeds. The results of the analytical and numerical simulations are compared with experimental results reported in the literature. r
Dynamic Effects Under Gaseous Detonation and Mechanical Response of Piping Structures
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Science and Technology of Energetic Materials. – 2011. – Vol. 72, No. 4. – P. 116 – 122., 2011
The mathematical model, the numerical method and the parallelization technique are presented for the problems of detonation initiation by means of comparatively weak shock wave and propagation of detonation waves in threedimensional tubes of complex shapes. The mechanisms of detonation initiation in a tube with parabolic contraction and cone expansion and in a helical tube are analyzed. The results obtained are of interest both for basic research contributing to understanding of the mechanism of detonation initiation in tubes with curved walls and for applications from point of view of predictive modeling of accidents in chemical industry.
Numerical simulation of detonation initiation in a contoured tube
Combustion, Explosion, and Shock Waves. – 2009. – Vol. 45, No. 6. – P. 700 – 707., 2009
The effect of the wall contours in an axisymmetric tube on the transition from the shock wave to the detonation wave is studied numerically. Qualitative features and quantitative characteristics of the detonation initiation mechanism realized in a tube with a parabolic segment of the wall contour and conical expansion are found. The calculated results are presented in the form of "detonation curves" (angle of inclination of the contoured segment versus the Mach number of the initial shock wave) for various levels of tube blockage ratio.
International Journal of Pressure Vessels and Piping, 2010
Analytical solution of transverse shear strain vibration of a tube caused by internal gaseous detonation near the second critical speed (shear group velocity) is not reported in the literature. It is performed based on a steady state model and first order shear deformation theories (model I and II) in this paper, and the results are verified through comparison with the finite element results reported in the literature. There are no known experimental ways of directly measuring dynamic transverse shear strain and only theoretical results and numerical data are available. The finite element method is very time consuming compared with the analytical solution. It is shown in this paper that the resonance phenomenon of the transverse shear strain vibration near the second critical speed can be predicted by steady state model and first order shear deformation theories. The first order shear deformation theory (model II) has a good agreement with finite element results in prediction of dynamic amplification factors and critical speeds.
Detonation-driven fracture problems in tube under dynamic load have received plenty of attention because of various ranges of applications, such as oil and gas pipeline systems, new rocket engine such as pulse detonation engine, and pressurized aircraft fuselages. This paper reports the crack growth modeling in a thin aluminum tube under gaseous detonation load. Because of three-dimensional fracture dynamics with gas dynamics coupled phenomena, analytical modeling is complicated. Thus, a finite element method was applied. The finite element modeling and simulation of the tube under detonation moving load were performed using commercial code Abaqus. This simulation leads to obtain structural response of the tube to detonation load. The simulations were compared with experimental and analytical results from the literature for elasto-dynamic response of cylindrical shells with finite length under internal detonation loading. Cohesive element with traction–separation law was used for crack growth modeling along with crack tip opening displacement value obtained from experimental–numerical analysis from previous research. The final section of the paper is dedicated to investigating differences and comparisons between the numerical crack propagation simulations and experimental results reported in the literature. It has been demonstrated that using cohesive elements with some modifications can improve the numerical accuracy. The obtained results are more similar to the experimental results than numerical results available in literature.
Study of detonation process: numerical approach
Proceedings of the 2nd Conference on European Computing Conference, 2008
This paper is based on non-linear finite element analysis of the effects of the blast wave on structures, caused by the detonation of explosive materials. Dynamic response of a pipeline subjected to the shock wave produced by the detonation of high explosive materials is presented in this paper. Coupled Euler and Lagrange formulation are used in the finite element analysis of such problems to accurately represent the detonation phenomenon. Preliminary results allow for detailed analysis of the blast wave propagation and its influence on the pipeline.
Detonation-Driven Tube Fracture–Experiments and Validation JE Shepherd, J
Experiments were carried out in FY04 on detonation wave structure, detonation wave diffraction, and the fracture of thin-walled tubes by detonation waves. Computations were performed on detonation wave propagation and the elastic response of tubes to detonation loading. One new effort was initiated on the diffraction of detonation waves, and the other activities were a continuation of previous efforts described in the FY03 annual report.
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 2011
Explosive loading of closed cylindrical structures is one of the most complicated types of high rate loadings that can be applied on fully closed structure. Considering the complexities and unknown factors that affect the dynamic-plastic behaviour of a fully closed tubular shell under internal blast loading, the main objective of this article is to achieve a better understanding of the deformation of such a structure through different theoretical, empirical and also numerical approaches. Based on some simplifying assumptions, a new pressure–time profile for the internal explosive loading of cylindrical shells whose length is shorter than its diameter would be introduced in this manuscript. Afterwards, the fundamental equations of motion would be solved by the use of the aforementioned profile so that a practical formula for the calculation of maximum radial deformation of shell would be obtained. Comparison between the theoretical values and the results of the experimental tests con...