Experimental of Ballast Free System with Air-Injected Pressure Bubbles in Reducing Ship Resistance

The discharge of ballast water may introduce and transport unwanted marine organisms to the discharging area. Marine Environment Protection Committee (MEPC) IMO consider action as hazard due possibility having negative impact on receiving ecosystems. Many researchers have investigated possible solutions for management minimize risks including free system. concept system is replace conventional avoid use costly treatment However, application has created a new issue ship hull resistance. objectives this research are determine effect LNG resistance how air-injected pressure bubbles affecting overall performance. To achieve objectives, experimental tests in towing tank been carried out at Froude number 0.17 0.22 air-injection 0.5bar, 1.0bar 1.5bar. increased total range 5% 16%. reduced by 29.8% 8.9% average 0.5bar injection respectively. For 1.5bar pressure, certain speeds slightly 1.34% average. optimum reduction occurred 0.19 pressure. finding can be served guideline modification configuration numerical mode comparison real conditions.