Structural Performance of Candidate Ablatives for Uptake Section of Vertical Launching System.

The structural performance of several candidate ablatives for the uptake section of the Navys Vertical Launching System is investigated. The uptake is modeled using a fixed-fixed beam-loaded by a uniform pressure. Beam displacement field equations are solved, assuming that the ablatives exhibit bimodular behavior in tension and compression. The candidate ablatives are ranked according to predicted structural performance. The current uptake ablative, MXBE-350, possesses the highest factor of safety in this analysis, although all but one of the ablatives considered appears to be acceptable. Additionally, the effects of erosion on the magnitudes of the peak stresses seen by the virgin ablatives are analyzed by varying the thickness of the ablatives in the uptake. As the thickness of the ablative decreases, the peak stresses in the ablative decrease. Finally, the effect of the stiffness of the ablative on predicted stresses in the adhesive layer is computed. As the elastic modulus of the ablative increases, the stresses in the adhesive decrease.