U-bend ducts are met frequently in industrial applications, such as the cooling vanes of turbine blades. This application pertains to the shape optimization of such a duct, targeting the reduction of total pressure losses between the duct’s inlet and outlet. Within just 20 optimization cycles, a gradient-based optimization executed within OpenFOAM reduced losses by almost 45%! This was achieved by almost eliminating the recirculation zone just after the U-bend. 

Initial (left) and optimized (right) duct geometries along with the two slices on the middle of the duct height and the middle of the transversal flow direction, showcasing the velocity magnitude.