Safety front shock damper (shock absorber) to protect containers in emergency falling

The article presents a front shock damper (shock absorber) for protecting containers with flying machines against fractures in case of emergency falling in the process of transportation and operation. Two numerical methods are proposed to calculate the stress-strain state and acceleration braking of a shock absorber in case of a vertical fall and impact with a stationary concrete surface. The methods are based on the use of ANSYS Workbench 16.1. The first technique consists in determining the stress-strain state on the assumption of quasi-static loads. The second, dynamical, method makes it possible to determine the reaction of a shock absorber to its impact with the concrete surface depending on time. What makes our technique special is that we take into account plastic properties of a material and actual contacts between the damper components. The methods proposed are validated by the analytical solution of the differential equation of container motion with the shock absorber in the elastic strain range. The methods are illustrated by an example of calculating a given damper. The results obtained by three methods show quite good agreement taking into account the calculation error. It is established that the energy of the shock absorber plastic-elastic strain upon an impact is more than half of the kinetic energy of the shock absorber in motion. The dependence of the shock-absorber braking acceleration both on the size of the crumpled area and on the time is determined.