Kirigami, the practice of cutting patterns into thin sheets of material, has found several applications in recent years due to the complex geometric changes and emergent physical properties that arise when these materials are exposed to external forces. In this ongoing research, we show that when kirigami sheets are placed in fluid flow, they create a complex fluid-structure interaction (FSI) system that exhibits a variety of structural and fluid dynamic behaviors. Some patterns allow the material to smoothly elongate to a significant degree, but others give rise to instabilities such as buckling or limit cycle oscillations. Each type of pattern also creates a characteristic wake that evolves as the extent of the sheet's deployment changes. We have observed arrays of jets whose magnitude and orientation can be controlled through changes in the pattern geometry and incoming flow velocity, as well as vortex shedding at multiple length scales, ranging from the size of the individual cuts, up to the size of the overall cut pattern.
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