Using a Ship's Propeller for Hull Condition Monitoring

摘要

As a ship's hull condition degrades due to marine fouling, more power and fuel are needed to maintain service speeds. One by-product of this increased fuel consumption is increased greenhouse gas emissions. Rising fuel costs, hull maintenance expenses, and mounting environmental regulations make hull condition monitoring a crucial tool for prudent ship operators, to eliminate energy waste due to hull fouling, to reduce carbon emissions, and to eliminate the carriage of invasive species between ports. Methods for using a ship's propeller as a power absorption dynamometer employ the propeller as a measuring instrument to estimate either speed or power. The calibration is typically performed for clean hull conditions, allowing the resulting propeller model to be used to track ship performance degradation due to hull fouling against a standard "clean-hull" baseline. The propeller power absorption technique is presented, along with the salient results of using it to monitor two U.S. Navy sister ships over a one-year long time period. This information may be useful for U.S. Navy decision makers who are responsible for hull/propeller maintenance and hull paint selection