The airbag simulation used by Radioss uses a special uniform
pressure airbag. Hence, regardless of state of inflation or shape, the pressure remains
uniform.
Perfect gas law and adiabatic conditions are assumed. Injected mass and temperature are defined as a time function. A sensor can define the inflater starting time.
Deflation of vent hole is available after reaching a pressure () for a given duration or at time () criteria. prevents deflation due to initial peak of pressure corresponding to
the jetting activation.Figure 1. Uniform Pressure Airbag
The key assumptions are:
Uniform airbag pressure kinetic energy is
negligible
Adiabatic conditions
The airbag simulation must include:
Injection of energy and mass
Bag mechanics (that is, unfolding, expansion, membrane tension, impacts, ...)