To simulate explosion fragments, it is necessary to predict many variables such as fragment velocity, size distribution and projection angle. For active protection systems these predictions need to be made very quickl...To simulate explosion fragments, it is necessary to predict many variables such as fragment velocity, size distribution and projection angle. For active protection systems these predictions need to be made very quickly, before the weapon hits the target. Fast predictions also need to be made in real time simulations when the impact of many different computer models need to be assessed. The research presented in this paper focuses on creating a fast and accurate estimate of one of these variables - the initial fragment velocity. The Gurney equation was the first equation to calculate initial fragment velocity. This equation, sometimes with modifications, is still used today where finite element analysis or complex mathematical approaches are considered too computationally expensive. This paper enhances and improves Breech’s two-dimensional Gurney equation using available empirical data and the principals of conservation of momentum and energy. The results are computationally quick, providing improved accuracy for estimating initial fragment velocity. This will allow the developed model to be available for real-time simulation and fast computation, with improved accuracy when compared to existing approaches.展开更多
Explosion models based on Finite Element Analysis(FEA)can be used to simulate how a warhead fragments.However their execution times are extensive.Active protection systems need to make very fast predictions,before a f...Explosion models based on Finite Element Analysis(FEA)can be used to simulate how a warhead fragments.However their execution times are extensive.Active protection systems need to make very fast predictions,before a fast attacking weapon hits the target.Fast execution times are also needed in real time simulations where the impact of many different computer models is being assessed.Hence,FEA explosion models are not appropriate for these real-time systems.The research presented in this paper delivers a fast simulation model based on Mott’s equation that calculates the number and weight of fragments created by an explosion.In addition,the size and shape of fragments,unavailable in Mott’s equation,are calculated using photographic evidence and a distribution of a fragment’s length to its width.The model also identifies the origin of fragments on the warhead’s casing.The results are verified against experimental data and a fast execution time is achieved using uncomplicated simulation steps.The developed model then can be made available for real-time simulation and fast computation.展开更多
The majority of allied casualties from recent conflicts were caused by blast wave and fragments perforation damage from Improvised Explosive Devices. Survivability to this type of threat is a critical factor to consid...The majority of allied casualties from recent conflicts were caused by blast wave and fragments perforation damage from Improvised Explosive Devices. Survivability to this type of threat is a critical factor to consider for land platform design. This paper proposes an original approach to platform survivability assessment using a combination of Agent-Based(AB) simulation and Fault Tree Analysis(FTA) to predict the consequences of IED fragment impacts on the platform operational status. As a demonstration, this approach is applied to the comparison of different platform architectures to gain insight into the optimisation of the platform component topology.展开更多
文摘To simulate explosion fragments, it is necessary to predict many variables such as fragment velocity, size distribution and projection angle. For active protection systems these predictions need to be made very quickly, before the weapon hits the target. Fast predictions also need to be made in real time simulations when the impact of many different computer models need to be assessed. The research presented in this paper focuses on creating a fast and accurate estimate of one of these variables - the initial fragment velocity. The Gurney equation was the first equation to calculate initial fragment velocity. This equation, sometimes with modifications, is still used today where finite element analysis or complex mathematical approaches are considered too computationally expensive. This paper enhances and improves Breech’s two-dimensional Gurney equation using available empirical data and the principals of conservation of momentum and energy. The results are computationally quick, providing improved accuracy for estimating initial fragment velocity. This will allow the developed model to be available for real-time simulation and fast computation, with improved accuracy when compared to existing approaches.
文摘Explosion models based on Finite Element Analysis(FEA)can be used to simulate how a warhead fragments.However their execution times are extensive.Active protection systems need to make very fast predictions,before a fast attacking weapon hits the target.Fast execution times are also needed in real time simulations where the impact of many different computer models is being assessed.Hence,FEA explosion models are not appropriate for these real-time systems.The research presented in this paper delivers a fast simulation model based on Mott’s equation that calculates the number and weight of fragments created by an explosion.In addition,the size and shape of fragments,unavailable in Mott’s equation,are calculated using photographic evidence and a distribution of a fragment’s length to its width.The model also identifies the origin of fragments on the warhead’s casing.The results are verified against experimental data and a fast execution time is achieved using uncomplicated simulation steps.The developed model then can be made available for real-time simulation and fast computation.
文摘The majority of allied casualties from recent conflicts were caused by blast wave and fragments perforation damage from Improvised Explosive Devices. Survivability to this type of threat is a critical factor to consider for land platform design. This paper proposes an original approach to platform survivability assessment using a combination of Agent-Based(AB) simulation and Fault Tree Analysis(FTA) to predict the consequences of IED fragment impacts on the platform operational status. As a demonstration, this approach is applied to the comparison of different platform architectures to gain insight into the optimisation of the platform component topology.
