Recycle Processor for Commercial Aircraft Wing Trimmings

Tons of composite trimmings are regularly generated as a result of current production methods in commercial aircraft wing component fabrication. Specific to this proposal, a local facility produces trimmings that range in thickness from about a centimeter to over two inches thick and varying widths from a few inches to six inches and lengths up to five feet. Reducing the cost of the disposition of these trimmings and a reduction of waste to landfill are the primary motivations for this work. A processor was devised that both separates fiber and reduces volume. This device is a vertical crusher/roller into which the ‘boards’ are inserted. An initial cogged wheel delaminates much of the board. Secondary wheels and hammers crush the matrix. The resulting matrix is captured at the bottom, while the fibers are pulled off to a side roller. Preliminary testing of a prototype indicates that a composite board takes 156 ksi to initiate delamination in bending. A sub-size device with components was designed and built. The device was designed in the fall of 2017 and constructed over the winter. By spring the system was operational and test data was generated for the processor. Test parameters include percent and amounts of recovered fiber, processing rates related to all the composite constituents, packing volumes, and overall energy management. A report was generated in concurrence with our MET489 Senior Project capstone course by the end of the current academic year.

Simple and Versatile Dynamic Model of Spherical Roller Bearing

Rolling element bearings are essential components of rotating machinery. The spherical roller bearing (SRB) is one variant witnessing increasing use because it is self-aligning and can support high loads. It is becoming increasingly important to understand how the SRB responds dynamically under a variety of conditions. This study introduces a computationally efficient, three-degree-of-freedom, SRB model that was developed to predict the transient dynamic behaviors of a rotor-SRB system. In the model, bearing forces and deflections were calculated as a function of contact deformation and bearing geometry parameters according to the nonlinear Hertzian contact theory. The results reveal how some of the more important parameters, such as diametral clearance, the number of rollers, and osculation number, influence ultimate bearing performance. One pair of calculations looked at bearing displacement with respect to time for two separate arrangements of the caged side-by-side roller arrays, when they are aligned and when they are staggered. As theory suggests, significantly lower displacement variations were predicted for the staggered arrangement. Following model verification, a numerical simulation was carried out successfully for a full rotor-bearing system to demonstrate the application of this newly developed SRB model in a typical real world analysis.