Energy release model of compaction band propagation

2005 ◽  
Vol 32 (16) ◽  
Author(s):  
J. W. Rudnicki
Keyword(s):  
Energy Release ◽  
Compaction Band ◽  
Release Model

scholarly journals Description of Muzzle Blast by Modified Ideal Scaling Models

1998 ◽  
Vol 5 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Kevin S. Fansler
Keyword(s):  
Energy Release ◽  
Location Parameter ◽  
Forward Direction ◽  
Data Correlation ◽  
Muzzle Blast ◽  
Data Scatter ◽  
Scaling Models ◽  
Two Parameters ◽  
Release Model ◽  
Instantaneous Energy

Gun blast data from a large variety of weapons are scaled and presented for both the instantaneous energy release and the constant energy deposition rate models. For both ideal explosion models, similar amounts of data scatter occur for the peak overpressure but the instantaneous energy release model correlated the impulse data significantly better, particularly for the region in front of the gun. Two parameters that characterize gun blast are used in conjunction with the ideal scaling models to improve the data correlation. The gun-emptying parameter works particularly well with the instantaneous energy release model to improve data correlation. In particular, the impulse, especially in the forward direction of the gun, is correlated significantly better using the instantaneous energy release model coupled with the use of the gun-emptying parameter. The use of the Mach disc location parameter improves the correlation only marginally. A predictive model is obtained from the modified instantaneous energy release correlation.

Research on work efficiency and energy release model of Al/PTFE mixture under electric ignition

2021 ◽  
Vol 127 ◽  
pp. 105517
Author(s):  
Enling Tang ◽  
Chang Liu ◽  
Yafei Han ◽  
Chuang Chen ◽  
Mengzhou Chang ◽  
...  
Keyword(s):  
Energy Release ◽  
Work Efficiency ◽  
Release Model

A Study on Damage Properties of Explosive Internal-Blast of Concrete

2012 ◽  
Vol 598 ◽  
pp. 420-424
Author(s):  
Qing Tao Wang ◽  
Jue Ding ◽  
Meng Kan Ying ◽  
Bao Liang Zhang
Keyword(s):  
Energy Release ◽  
Numerical Study ◽  
Damage Effect ◽  
Building Structures ◽  
Sph Method ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Detonation Process ◽  
Release Model ◽  
Heavy Damage

Blast can cause serious loss of people live and property，and heavy damage on building structures. So, a numerical study on internal-blast-field characteristics and dynamic response of concrete by aluminized explosive was conducted. Moreover, three energy release models of aluminized explosive with combustion effects were compared and analyzed. The numerical study shows that the ignition and growth model is one three-form equation of reaction rate, which can describe unsteady detonation process of non-ideal explosives well. So, in this paper, the energy release model of aluminized explosive based on the Lee-Tarver rate equation was utilized, and an internal-blast dynamic model of concrete was established. The smoothed particle hydrodynamics (SPH) method was adopted to research the explosion field and damage effects of concrete, and provides an important way to evaluate the damage effect of internal-blast of the concrete.

Calculating Energy Release Rate as a Function of Crack Length Using a Multiple-Step Crack Closure Technique in Tire Finite Element Models

2018 ◽  
Vol 46 (3) ◽  
pp. 130-152
Author(s):  
Dennis S. Kelliher
Keyword(s):  
Finite Element ◽  
Energy Release Rate ◽  
Crack Length ◽  
Energy Release ◽  
Crack Closure ◽  
Release Rate ◽  
Fatigue Behavior ◽  
Three Dimensions ◽  
Quantitative Prediction ◽  
Closure Technique

ABSTRACT When performing predictive durability analyses on tires using finite element methods, it is generally recognized that energy release rate (ERR) is the best measure by which to characterize the fatigue behavior of rubber. By addressing actual cracks in a simulation geometry, ERR provides a more appropriate durability criterion than the strain energy density (SED) of geometries without cracks. If determined as a function of crack length and loading history, and augmented with material crack growth properties, ERR allows for a quantitative prediction of fatigue life. Complications arise, however, from extra steps required to implement the calculation of ERR within the analysis process. This article presents an overview and some details of a method to perform such analyses. The method involves a preprocessing step that automates the creation of a ribbon crack within an axisymmetric-geometry finite element model at a predetermined location. After inflating and expanding to three dimensions to fully load the tire against a surface, full ribbon sections of the crack are then incrementally closed through multiple solution steps, finally achieving complete closure. A postprocessing step is developed to determine ERR as a function of crack length from this enforced crack closure technique. This includes an innovative approach to calculating ERR as the crack length approaches zero.

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