Finite Element Analysis (FEA) was performed in SolidWorks on proposed Membrane Chamber Models. Simulations were performed for three different designs of the hole and peg straining system, a slotted system, a two peg system, and a three peg system. The slotted system extensively stretched the wall of the chamber; and therefore, this design had minimal stretching effects on the actual chamber area. This design was ruled out since the desired stretching response should be focused in the chamber area (since this is where the cells will be growing). The three and two peg designs both have increased stress distributions across the entire membrane; however, it appeared that the three peg design exhibited stress concentrations on the left side of the membrane (side of the membrane in motion). The two peg design produced desired stretching effects in the membrane area, and the stresses are more evenly distributed across the membrane when compared to the three peg design. Fillet dimensions have been modified in an attempt to distribute stresses across the membrane evenly; however, results have been inconclusive and more design options will be explored in the detailed design phase.
NOTE:In the design (and as modeled below), two pegs will remain stationary, while two pegs will cyclically move and stretch the membrane. Concerns for stress build-up lie near the two pegs that will be in motion.