Development of Ultra-High Efficiency, Silent Dual Propeller... "For Stealth Warships"

Korea Electrotechnology Research Institute Develops World's First 'Non-Contact Magnetic Gear-Based Counter-Rotating Propeller' Technology
Utilizing Magnetic Principles, Achieves 10% Improvement in Propulsion Efficiency and Minimizes Noise

Korea Electrotechnology Research Institute's 'Non-contact Magnetic Gear Based Counter-Rotating Propeller' (left for ships, right for aircraft)

[Asia Economy Reporter Kim Bong-su] Domestic researchers have developed a technology for the first time in the world that uses magnets to rotate two propellers in opposite directions, minimizing noise while improving propulsion efficiency by 10%. This technology is attracting attention for its potential use in stealth vessels and submarines.

The Korea Electrotechnology Research Institute (KERI) announced on the 7th that Dr. Hong Do-gwan's team at the Electric Power System Research Center has developed the world's first "non-contact magnetic gear-based counter-rotating propeller" technology that can improve the propulsion efficiency of ships and aircraft by more than 10%.

The "counter-rotating propeller" consists of two propellers rotating in opposite directions arranged along the shaft axis. The rotational energy generated by the front propeller is recovered and recycled as the rear propeller rotates in the opposite direction. Therefore, it offers high propulsion efficiency and energy-saving effects, leading to extensive research both domestically and internationally. The problem lies in the need for a so-called "mechanical gear," where teeth mesh to transmit power, which causes significant heat, noise, and vibration due to friction, as well as requiring regular maintenance such as lubrication supply for wear and cooling.

The research team solved this problem by developing a "non-contact magnetic gear" that transmits power without contact between gear components by utilizing the repulsive and attractive forces between the N and S poles of magnets, thereby generating propulsion for the counter-rotating propeller. They focused on the inherent capability of magnetic gears to enable counter-rotation and applied this to underwater and aerial propulsion systems.

The team overcame challenges in component combination and design, electro-mechanical performance analysis, prototype production, and performance testing. Recently, they completed a demonstration test of an underwater thruster using the non-contact magnetic gear near KERI's Changwon headquarters reservoir, achieving a maximum efficiency of 99%.

The counter-rotating propeller equipped with the non-contact magnetic gear offers not only high propulsion efficiency and fuel cost savings but also almost no noise and vibration due to the use of non-contact magnetic forces. These advantages are expected to be highly valued in the defense sector. Additionally, the nearly permanent lifespan of the system means minimal maintenance is required, which is another significant strength.

Dr. Hong stated, "The existing method is 'motor + single propeller,' and the next step is 'motor + complex mechanical gear + counter-rotating propeller.' Our achievement goes one step further by applying the world's first non-contact magnetic gear to replace mechanical gears." He added, "We will continue research and development to expand the application of our non-contact magnetic power transmission technology beyond underwater and aerial uses to various mobility fields."

Currently, the non-contact magnetic gear-based counter-rotating propeller developed by the research team has an output level of 3kW for unmanned vehicles. Through continuous research, they aim to achieve 10kW for unmanned vehicles this year and realize over 100kW performance next year, sufficient to carry dozens of people.

This content was produced with the assistance of AI translation services.