Topology optimization of the thin-walled honeycomb core at fixed mass and volume occupancy for enhancing the sandwich panel’s air blast mitigation performance
Murlidhar Patel, Shivdayal Patel, Neeraj Kumar Bhoi, Santhosh Kumar Kamarapu, Shivanku Chauhan
Abstract
Air blast attacks are rapidly increasing in the current scenario, resulting in lots of people severely injured and losing their lives, and infrastructures are critically damaged. Honeycomb sandwich panels have outstanding specific strengths with efficient energy-absorbing ability and are widely employed as protective panels against extreme air blast loadings. Improvement in the air blast mitigation performance of the honeycomb sandwich panels without increasing their mass and volume occupancy is the challenging task for weight-critical applications. Therefore, in the present explicit numerical study, the effect of honeycomb core topologies (square, reentrant, octagonal, and circular) on the blast performance of the high-strength AL-6XN sandwich panels is investigated at constant mass and volume for 1–3 TNT air blast loadings. The unit cell volume occupancy of the different honeycomb cores is also maintained constantly. The rate-dependent Johnson-Cook material model was used for achieving realistic plastic deformations in the designed sandwich panels. To identify an optimal honeycomb core design, the blast performance of the designed honeycomb sandwich panels of the equal mass is compared in terms of their face sheets center point deflections, face sheets radial deflections, changes in kinetic energy, changes in internal energy, plastic dissipation energy (PDE), deformation modes, and equivalent plastic strain (PEEQ) of the core structures. The obtained results indicated that the circular honeycomb core used sandwich panels have better blast resistance than the other designed sandwich panels of the identical mass in terms of smaller back face sheet’s center point deflection and radial deflection and higher energy absorption by the core structure. Hence, the circular honeycomb core is the most suitable candidate for designing protective structures against blast attacks, such as skid plates of armor vehicle.