The dynamometers have been designed for low friction torque at the propeller shaft and for this reason shaft seals are not fitted. As a result, the dynamometers are not watertight. If watertight propeller dynamometers are required, alternative designs are available. All dynamometers have a similar appearance although vary in size / rating to suit the intended specification required. The Dynamometers are compact with low weight and small dimensions and as such are suitable for use with models over a wide range of sizes however also offer with suitable accessories the ability of mounting two dynamometers driven through a gear box to allow the testing of twin screw models. The self propulsion dynamometer measures thrust and torque of the propellers during propulsion tests with ship models on smooth water and in waves in towing tanks.
....
