Breathing surfaces: Tension-Activated Kirigami (TAK) for passive airflow control in natural ventilation

This paper presents a computational design framework for integrating Tension-Activated Kirigami (TAK) into curvilinear architectural surfaces for passive airflow control. Conventional ventilation strategies often rely on fixed geometries or mechanically actuated components, which can limit adaptability and increase system complexity. This study explores an alternative approach in which airflow modulation is embedded within geometric design and material response. Drawing on kirigami principles, TAK patterns introduce strategic cuts that allow flat sheets to transform into strain-responsive surfaces, forming directional apertures under tension. The framework combines parametric modeling, finite element analysis (FEA), and computational fluid dynamics (CFD) within a coupled design process that relates geometric parameters to both structural deformation and airflow behavior. Simulation and prototyping are used to examine how variables such as slit-to-wall ratio and curvature-informed pattern distribution influence aperture formation and flow performance. The results show that TAK surfaces can redirect airflow, promote air mixing, and reduce stagnation, while maintaining controllable deformation under applied strain. These findings suggest that ventilation performance can be achieved through the interaction of geometry and material behavior, offering a low-energy and adaptable strategy for architectural applications such as roofs, façades, and lightweight enclosures.