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As part of the General Education (GenEd) program at the Pennsylvania State University, we offer an experimental course on flow visualization to undergraduate students. This course aims to bridge the gap between two distinct areas of knowledge: the art and science of fluid mechanics. Designed for students with minimal to no background in photography or physics, this nonmathematical course provides an opportunity for students to explore a variety of aesthetic issues through practical and creative assignments. The course consists of lectures on photography skills, fluid physics, visualization techniques, critique sessions, and a guest lecture. Assignments consist of images paired with written technical reports, and critique sessions. The primary objective of the course is "integrative thinking". Other course objectives evaluated through students’ assignments and projects are "creative thinking" and “effective communication”. Some samples of student work are presented, and the outcomes are discussed. This course proved to be very successful in attracting all students (male and female) in both engineering and non-engineering majors. 

In revolving or flapping wings, radial planetary vorticity tilting (PVTr) is a mechanism that contributes to the removal of radial (spanwise) vorticity within the leading-edge vortex (LEV), while vorticity advection increases its strength. Dimensional analysis predicts that the PVTr and advection should scale with the wing aspect-ratio (AR) in identical fashion, assuming a uniform characteristic length is used. However, the authors’ previous work suggests that the vorticity advection decreases more rapidly than the PVTr as AR increases, indicating that separate normalizations should be applied. Here, we aim to develop a comprehensive scaling for the PVTr and vorticity advection based on simulation results using computational fluid dynamics. Two sets of simulations of revolving rectangular wings at an angle of attack of 45° were performed, the first set with the wing-tip velocity maintained constant, so that the Reynolds number (Re) defined at the radius of gyration equals 110, and the second set with the wing angular velocity maintained constant, so that Re defined at one chord length equals 63.5. We proposed two independent length scales based on LEV geometry, i.e., wing-span for the radial and tangential directions and wing chord for the vertical direction. The LEV size in the radial and tangential directions was limited by the wing-span, while the vertical depth remained invariant. The use of two length scales successfully predicted not only the scaling for the PVTr and the vorticity advection but also the relative magnitude of advection in three directions, i.e., tangential advection was strongest, followed by the vertical (downwash) and then the radial that was negligible.