Images © Van Oossanen & Associates b.v.

We were asked to provide support in determining the flow and loading on a zero-speed fin for Quantum Controls. This company is constantly improving the design of their zero-speed fins so as to be able to reduce the fin area for a given performance. It is well known that non-retractable zero-speed fins possess an appreciable drag, with an important impact on attainable speeds, particularly at high speed.

Computational Fluid Dynamics (CFD) calculations revealed these fins to possess a very complex flow behaviour as can be seen from the figures.