Abstract: m-fold symmetric vortex patch solutions form a particularly important class of vortex solutions for the incompressible Euler equations. In the two-dimensional case, numerous results exist. For example, the characteristic function of a disk centered at the origin represents a trivial vortex patch solution. Another well-known example is the Kirchhoff vortex patch. For the 3D incompressible Euler equations, however, while several results have been established for solutions with vorticity highly concentrated along helically symmetric curves (featuring small cross-sections), helical symmetric solutions with large cross-sections remain scarce. This talk presents joint work in which the Crandall–Rabinowitz bifurcation theorem is applied to prove the existence of m-fold symmetric helical vortex patch solutions (also known as m-fold Kelvin waves), whose cross-sections approximate disks. This talk is based on joint work with Daomin Cao, Boquan Fan and Guolin Qin.