FEA and CFD Based Simulation of Blast, Explosion & Fire
Contemporary design requirements associated with the protection of life and property often require consideration for blast effects resulting from either accidental or intentional explosions. Proper treatment of blast effects in structural systems requires specialized knowledge ranging from non-linear responses of structures to short-duration dynamic loading. Enteknograte’s Research engineers have extensive training and experience in managing all structural response considerations related to high-energy events, including blast design, explosion effects and mitigation, and finite clement modeling of blast events.
Design and validation of structures against blast loads are important for modern society in order to protect and secure its citizen. Since it is a challenge to validate and optimise protective structures against blast loads using full-scale experimental tests, we have to turn our attention towards advanced numerical tools like the finite element method. Several different finite element techniques can be used to describe the response of structures due to blast loads. Some of these are:
- A pure Lagrangian formulation,
- An initial Eulerian simulation (to determine the load) followed by a Lagrangian simulation (for the structural response) and
- A hybrid technique that combines the advantages of Eulerian and Lagrangian methods to have a full coupling between the blast waves and the deformation of the structure.
Ideally, all blast simulations should be carried out using the fully coupled Eulerian-Lagrangian approach, but this may not be practical as the computational time increases considerably when going from a pure Lagrangian to a fully coupled Eulerian-Lagrangian simulation.
Enteknograte engineers simulate the Blast and Explosion with innovative CAE and virtual prototyping available in the non-linear structural codes LS-DYNA, Ansys Autodyn, and ABAQUS. Enteknograte Engineers can simulate any type of Blast and Explosion such as air blast, Underwater explosion (UNDEX) and Fragmentation due to blast to survey structural integrity in High Rate Loading Condition.
Our engineers have strong backgrounds in FEM(Finite Element Method) and complicated Multiphysics simulation that need deep knowledge and are fluent in the codes like LS-DYNA, Ansys and ABAQUS. We can develop special purpose user subroutine (UMAT) based on clients need to empower simulation environment to overcome any complicated problem in Blast and explosion load condition and user defined material constitutive equation for composites and special purpose Concrete including fracture mechanics of concrete in different strain rate.
Computational Fluid Dynamics for BLAST, Explosion and Fire simulation
Blast loads on buildings can be determined through the use of computational fluid dynamics (CFD) computer programs. The basic premise of CFD modeling is to discretize the building and surrounding area encompassing the blast source and adjacent obstacles into small regular cells of finite volume and then solve the governing equations for conservation of mass, momentum, and energy within each cell, taking into account the effects of adjacent cells.
Among other uses, CFD is utilized to simulate the propagation of blast waves in an environment of obstacles, to simulate pressures on unusually-shaped buildings, to simulate leakage through openings into buildings, to simulate interior explosions, and to simulate near-field explosion effects. Where applicable, CFD can be used as an alternative to the more commonly used empirical methods.
It should be understood that CFD results are sensitive to modeling techniques and the software used. CFD programs can employ a true first principles approach which includes turbulence modeling and detailed combustion, or a semi-empirical approach where simplifications of the explosion source are made, based on test data and guidance, to simplify and speed the analysis. Phenomological models are sometimes used to simplify the analysis by using numerical modeling of selected explosion phenomena to capture important features of blast propagation. As with most simulations, the greater the detail of the model, the greater the potential accuracy of the result.
By using Accurate mechanisms that representing every class of explosion and Fire important for this analysis and combination of advanced computational fluid dynamics (CFD) simulation tools such as Kiva, Ansys Fluent, Ansys Forte, AVL Fire, Converge CFD, Siemens Star-ccm+ enable Enteknograte engineering team to most detailed simulation of Fire and Explosion in industrial and defense projects.
Enteknograte Research Blast engineering and Explosion mitigation capabilities include:
- The use of methods ranging from classical to nonlinear transient Finite Element Analysis (FEA)
- Industrial equipment subjected to accidental explosions
- Commercial curtain wall and window systems
- New construction and retrofit of existing systems
- Hardening of historical buildings
- Inventive solutions for unusual applications
Blast, Explosion and Fire simulation for Offshore Engineering
The finite element method (FEM) as a computational tool has been extensively used in the offshore industry. It has been applied both for global and local simulation to study the behavior of the offshore structures.
Design procedures for Blast and Explosion analysis of offshore structures
Explosions, fires and other accidents are major risks in the offshore industry. Extreme loads arising for structural from accidents create a challenge engineers in the design of safe and weight-efficient structures. The use of design procedures based on state-of-the-art computational technology allows for weight-optimised structural designs that meet defined safety requirements.
FE modelling for offshore structures resistant to explosions and fires
Design procedures for creating offshore structures resistant to explosions and fires are normally based on the selection of design principles such as deterministic, probabilistic and risk-based design.
Methods used in designing structures that are resistant to explosions and fires include simplified methods and non-linear FE modelling and analysis. FE models involve accurate description of modelling techniques including modelling of structures, materials, and fire and explosion loads.
Assessment of fire and explosion loads
Enteknograte performs assessment of fire and explosion loads using state-of-the-art CFD software. Based on assessments of fire and explosion loads, deterministic or probabilistic models of loads are established for direct use in the design process for offshore installations.
Enteknograte carries out structural design verification as well as studies of structures subjected to fires and explosions. Complex FE models of structures are developed and used in response and structural strength simulations.
Blast-resistant walls and partitions for offshore structures
The following aspects are normally considered in order to achieve an optimum design of blast-resistant walls and partitions:
- Definition of design explosion and fire loads
- Establishment of the behavior of materials to be used for the design for high rate loads
- Determination of the behavior and strength of walls by means of non-linear FE modelling
FEA and CFD Based Simulation
Reduce Development Cost
Test Before Manufacturing
Considering complexity and needs to have new procedure and constitutive equation, we must try to develop new FEA and CFD based software to overcome engineering challenges.
FEA and CFD based Programming needs experience and deep knowledge in both Solid or fluid mechanics and programming language such as Matlab, Fortran, C++ and Python.
We use subroutine’s with programming languages such as Fortan, C and Python in CFD and FEA sofware such as Abaqus, Ansys, Fluent and Star-ccm+ to add new capability and Constitutive equation.