ABSTRACT
This work focused on creating a numerical model of an inflatable low density polyethylene (LDPE) bag that is able to model the stiffness and the inflated shape of a physical LDPE inflatable bag relatively well. This numerical model, once validated, can then be extended to a model with the same properties but with a more complex geometry eventually resembling a wing. Three bags with constant lengths but differing diameters were compared, each inflated to three different pressures with at least two of the bag’s pressures overlapping with one another. The stiffness of the numerical model was validated through simulating 4-point bending tests with an explicit solver and then comparing the force-displacement data of the two. The geometry of the inflatable bags both under load and no-load were captured using a 3D scanner and then converted into point clouds. Outlines of the physical and numerical bags were then plotted together as well as the goodness of fit quantified using the Hausdorff distance and Frechet distance. The force-displacement data of the numerical and physical models compared well with generally small errors. When large deviations in the data did occur they only occurred for a small portion of the data. The Hausdorff and Frechet distances between the numerical and physical models were also relatively small showing a good correlation between the size and shapes of the bags.
