Design and vibration testing of a flexible seal whisker model

Abstract

Harbor seal whiskers have a unique surface structure that dramatically reduces vortex induced vibrations as they move through the water. Concurrently with rigid whisker experiments, this project focuses on the design and testing of a flexible model. The rubber model was cast with integrated Kevlar strings, for tensioning purposes, and accelerometers to measure vibration data. The whisker model was mounted to the carriage in the MIT tow tank where it could be towed at a variety of speeds and tension settings. Accelerometer data clarity was a significant problem, but gradual improvements to the whisker mounting design allowed higher quality data to be gathered at a larger range of towing speeds. Using this data we observed correlations between towing speed, vibration frequency, g forces, and displacement in the whisker's vertical axis of motion. Further work could be done to examine whisker motion in multiple axes, as well as with different angles of attack.