Research

Aerospace Applications

An application that demonstrates the numerous detriments of the current process for design-to-analysis is related to unexpected tail buffeting of aircraft stabilizers due to flow disruptions, which has been identified as a critical issue in military aircraft that are outfitted for different types of missions. Under these conditions, the internal structure of the stabilizer offers critical support to ensure that the structure will not fail unexpectedly from increased fatigue due to buffeting. These types of structures that operate under varying conditions are extremely challenging to design and model using traditional methods that do not include a systematic, mission-specific approach. For this application, the internal structures in the horizontal stabilizer of a P-8A aircraft are parameterized to provide an efficient approach for achieving cost- or performance-based optimization to update or modify the structures to appropriately support new configurations or operating conditions. The patch coupling approaches [2.1] that are used to couple the ribs and spars in the stabilizer can also be applied to the analysis of many other types of airframe structures, including multipatch airframe components in a UH-60 Black Hawk helicopter.

Biomedical Applications

For many patients with valvular heart diseases, bioprosthetic heart valves are critical structures that support the treatment of vital components in the cardiac system. Despite their important role in cardiac function for patients who have undergone heart valve replacements procedures, these valves that have faced numerous challenges related to design and durability in recent years. The effectiveness of using an approach that incorporates parametric design and IGA for valvular applications is clearly demonstrated by the modeling and analysis of the tricuspid valve (TV), which involves a geometric description of the complex primary structures of the TV [3.1,3.2]. This work has addressed the significant computational challenges of simulating the TV through a parametric model definition and analysis methods that capture the full structural deformation of the valve closure observed from medical data. The advantages of parametric IGA also support significant future advancements in identifying potential design or durability issues in bioprosthetic aortic heart valves in the cardiac system. Incorporating computational fluid–structure interaction based on immersogeometric analysis, the initiation of leaflet flutter was identified and quantified in thinner bioprosthetic aortic valve tissues [3.3]. This work highlighted that using thinner tissues in bioprosthetic implants may impact critical valve performance issues, such as leaflet flutter, that can reduce the reliability and safety of these devices.