There are a vast number of applications in which composite axial turbomachines could prove beneficial, however, current manufacturing methods can be time or cost prohibitive. Over the past several years, a novel manufacturing process aimed at reducing costs and improving structural properties has been under development at Michigan State University. This prior work established the basic manufacturing concepts and demonstrated the feasibility of utilizing the novel wound composite impellers for a number of applications in the renewable energy sector. The features of scalability and modularity put forth by this previous work have been promising. The resulting geometries that could be produced were limited to variations of the unconventional "star" pattern design. These designs generate approximately a solid body (i.e. forced vortex) swirl distribution. This work reflects a substantial improvement of the manufacturing process for wound composite impellers, while also allowing the manufacturing of any modern 3D shaped impellers with preferred swirl distributions. This was achieved through sophistication of the mandrel (mold) design and fiber layup process. By dry winding the fiber and then utilizing a vacuum assisted resin transfer molding method for the infusion process, high quality impellers were obtained. Both front and rear stage impellers of a multistage axial compressor were manufactured thereby demonstrating the flexibility of the new manufacturing process. Additionally, shaft driven and integrated drive motor configurations were designed and demonstrated. Overlaying a laser scanned model onto the CAD model of an impeller was used to visually inspect how well the resulting blade shapes matched the original design and the preliminary data indicated good agreement. Measurements of basic geometric dimensions like shroud diameter, tip radius, hub radius at leading/trailing edges and axial chord length were within 20% agreement with their design values with most below 10% and several within 1% agreement.
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