We provided our client with advanced blast modelling support to optimise and verify a new design. The task was to consider a mine detonation occurring beneath an armoured vehicle to a given threat level (STANAG-4569). We worked closely with the test house to ensure all details of the test set up and ground preparation were accurately captured within the model, for example, different hulls and soil types. Our approach significantly reduced costs due to the reduction in the amount of physical testing required.
Our client, a developer of a novel vehicle mine blast protection system, needed to verify the performance and optimise the design of the system before committing to costly, full-scale blast testing. All modelling activities needed to be validated against physical test data from ¼ scale blast trials.
We were asked to support the client with the provision of advanced blast modelling support through the use of ANSYS Autodyn, a piece of analytical software developed expressly with the purpose of simulating the response of materials to short duration severe loadings. The blast modelling task was to consider a mine detonation occurring beneath an armoured vehicle to a given threat level (STANAG-4569). The work was divided into 2 phases, initially modelling many detailed test setups, accounting for many variables, namely; charge size, soil type and vehicle hull form. Following successful validation of the analysis results against the testing data, the next stage of the work focussed on assessing the client’s new design and optimising the performance to provide proof of concept and quantify the potential benefit.
We began the task, by following our standard analysis framework. The first task to be completed was the generation of the detailed Analysis Plan; given the complexity of the modelling and number of combinations to be assessed, it was vital that there was a clear “reference” document, which all stakeholders reviewed and agreed prior to the commencement of the detailed modelling and physical testing. Once the methodology and approach had been developed, the initial focus of the work was to model the trials setup, so as to validate the modelling approach and response. Our engineers worked closely with the test house to ensure all details of the test set up and ground preparation was accurately captured within the analysis model. During the trials, various hull forms (different wedge angles) were tested along with a number of different soil types (dry sand, wet sand and clay as defined by AEP-55). Each trial was modelled within ANSYS Autodyn and a number of results extracted for comparison. Typically the items which were used to compare and correlate the result were; impulse, hull deformation and ejecta flow. Following the completion of the initial validation analyses, the most representative and accurate modelling setup was identified and used for all subsequent analysis. The second phase of the modelling work focussed on modelling the novel structure and quantifying the performance and optimisation of the design. All the work completed was summarised in a detailed report which was reviewed by an external 3rd party.
- We decreased risk; by validating the performance and response of the system without the need for physical testing.
- We reduced costs; this approach provided a significant reduction in the amount of physical testing required.
- We reduced time; the analysis approach was significantly quicker and allowed multiple iterations of design/setup.