Parametric Optimization of Magnetohydrodynamic Thrusters for Efficient and Silent Ocean Propulsion

Today’s propulsion systems have many problems, majorly noise caused by the propeller, air pollution and injuries caused to marine life. Every day over 60,000 ships sail and each of them travels around 1000kms. These ships affect over 130 species. The average sound level estimated globally from marine traffic is 100 Hz, based on average shipping activity directed from automatic identification system (AIS) data for 2014. Propellers rotate up to 250 revolutions per minute and these propellers are about 25% faster than an average fan, impacting marine life. These propellers can cause more drag, kill various species of fishes and can sometimes mercilessly chop them into pieces. Additionally, they induce cavitation which means they generate bubbles when they revolve and when these bubbles burst, frequencies of up to 20,000 hertz can be generated. Magnetohydrodynamic thruster is a new and evolving type of electric propulsion system which is devoid of moving parts, with aims of creating efficient and silent thrust. In this study, the effect of several electrode parameters such as length, spacing, magnetic field strength, input voltage and surface area on the output thrust are experimentally tested and verified to determine an optimum design. Environmental factors such as salt concentration and water temperature are monitored as well. The optimum parameters in this parametric study can be extrapolated to determine the same for a real life application.