Using CFD for Blast Wave Predictions
نویسندگان
چکیده
Explosions will, in most cases, generate blast waves. While simple models (e.g., Multi Energy Method) are useful for simple explosion geometries, most practical explosions are far from trivial and require detailed analyses. For a reliable estimate of the blast from a gas explosion it is necessary to know the explosion strength. The source explosion may not be symmetric; the pressure waves will be reflected or deflected when hitting objects, or even worse, the blast waves may propagate inside buildings or tunnels with a very low rate of decay. The use of computational fluid dynamics (CFD) explosion models for near and far field blast wave predictions has many advantages. These include more precise estimates of the energy and resulting pressure of the blast wave, as well as the ability to evaluate non-symmetrical effects caused by realistic geometries, gas cloud variations and ignition locations. This is essential when evaluating the likelihood of a given leak source as cause of an explosion or equally when evaluating the potential risk associated with a given leak source for a consequence analysis. In addition, unlike simple methods, CFD explosion models can also evaluate detailed dynamic effects in the near and far field, which include time dependent pressure loads as well as reflection and focusing of the blast waves. This is particularly valuable when assessing actual near-field blast damage during an explosion investigation or potential near-field damage during a risk analysis for a facility. One main challenge in applying CFD, however, is that these models require more information about the actual facility, including geometry details and process information. Collecting the necessary geometry and process data may be quite time consuming. This paper will show some blast prediction validation examples for the CFD model FLACS. It will also provide examples of how directional effects or interaction with objects can significantly influence the dynamics of the blast wave. Finally, the challenge of obtaining useful predictions with insufficient details regarding the geometry will also be addressed.
منابع مشابه
A New Method for Very Fast Simulation of Blast Wave Propagation in Complex Built Environments
The paper is concerned with the development of a fast, accurate, and versatile method of simulating the propagation of a blast wave within complex built environments. An ability to complete a simulation of the propagation of a blast wave within a few seconds or minutes is an essential tool for evaluating its impact on key structures and to find an optimal design for components such as blast bar...
متن کاملCFD prediction of ship capsize: parametric rolling, broaching, surf-riding, and periodic motions
Stability against capsizing is one of the most fundamental requirements to design a ship. In this research, for the first time, CFD is performed to predict main modes of capsizing. CFD first is conducted to predict parametric rolling for a naval ship. Then CFD study of parametric rolling is extended for prediction of broaching both by using CFD as input to NDA model of broaching in replacement ...
متن کاملEXPERIMENTAL EVALUATION OF BLAST WAVE PARAMETERS IN UNDERWATER EXPLOSION OF HEXOGEN CHARGES
Behavior of blast wave in underwater explosion is of interest to metal forming community and ship designers. Underwater detonation is, also a potential hazard to the water intakes or a plant spent fuel pool. In this paper, some techniques for calculating free-field blast parameters such as pressure and impulse in underwater explosion and prediction of bubble pulsation parameters are presented a...
متن کاملStructural Response of Offshore Plants to Risk-Based Blast Load
Offshore oil and gas process plants are exposed to hazardous accidents such as explosion and fire, so that the structural components should resist such accidental loads. Given the possibilities of thousands of different scenarios for the occurrence of an accidental hazard, the best way to predict a reasonable size of a specific accidental load would be the employment of a probabilistic approach...
متن کاملInvestigation of blast-induced traumatic brain injury
OBJECTIVE Many troops deployed in Iraq and Afghanistan have sustained blast-related, closed-head injuries from being within non-lethal distance of detonated explosive devices. Little is known, however, about the mechanisms associated with blast exposure that give rise to traumatic brain injury (TBI). This study attempts to identify the precise conditions of focused stress wave energy within the...
متن کامل