• Journal of Advanced Marine Engineering and Technology
• /
• v.34 no.8
• /
• pp.1128-1134
• /
• 2010

This paper is about the development of the 300W underwater thrusting system driven by a brushless DC motor (BLDC) for underwater robots. A design of the structure such as the structure analysis on the thrusting system using FEM and the design of the propeller using the fluid analysis has been performed. Also, a new structure such as decoupling and non-gear structure has been explained. The performance test of the designed and developed thrusting system in water and in air was undertaken and its results were compared with an existing product with high performance. The comparison results show that the developed thrusting system has better performance by 16% in forward thrusting force and by 12% in backward thrusting force.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.1142-1143
• /
• 2017

In this paper, Underwater propulsion test of SWASH(Small Waterplane Area Single Hull) type underwater vehicle with hybrid rocket system is performed. Watertight structure is applied to prevent a combustion chamber from water, and the control logic is constructed by setting the watertight ignition sequence. As a results, It is confirmed that the ignition is stable in water, and the propulsion system works well along the configured control sequence.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.120-127
• /
• 2017

High temperature oxygen and water vapor was generated from catalytic decomposition of rocket grade highly concentrated hydrogen peroxide, and monopropellant thruster system was developed and applied into space propulsion system. In this research, background research and conceptual design of underwater propulsion system using catalytic decomposition of hydrogen peroxide was progressed. Two types of system was designed with different steam injection methods. Propulsion system that has ring-type steam injector was manufactured and performance estimation of system was performed with different nozzle exit area. Performance evaluation with central steam injection type jet engine will be progressed in the future.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.23 no.3
• /
• pp.112-118
• /
• 2019

The development of an underwater rocket propulsion system was described in this paper. Throttle able liquid propellant and hybrid rocket propulsion systems were selected for underwater propulsion. A subscale liquid rocket combustion chamber and it's portable stand were developed and their applicability was examined. 1.5-ton.f and 1.8-ton.f hybrid rockets were developed for underwater applications. The test results indicated that the 18-ton.f hybrid rocket fully complies to the performance and underwater cruise stability requirements; thus, its development was concluded to be successfully complete.

• Journal of Navigation and Port Research
• /
• v.36 no.1
• /
• pp.35-41
• /
• 2012

In this paper, we analyze the current submarine cooling system and study control algorithms for cooling system. Cooling system are installed in the submarine propulsion motor to protect the motor from high-temperature by iron loss and copper loss. The cooling system control the sea water and fresh water pump RPM to keep the motor temperature stable by external environment and motor RPM holding time. The cooling system simulation program is made for checking the cooling performance, and simulation is performed with various control strategy. The results with proposed cooling algorithm is shown to improve the thermal stability and efficiency of cooling system.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.18 no.4
• /
• pp.50-60
• /
• 2014

Many countries are paying efforts to the research and development of water-breathing ramjet propulsion for submersible vehicle with the super-cavitation which makes traveling at high speed in underwater possible. In this study, a conceptual design of an underwater vehicle with water-breathing ramjet was carried out. Mission profiles and operating conditions are determined by examining the operation environment. Drag is estimated based on the theories of super-cavitation and fluid mechanics. The sizing and performance analysis of the components were performed using thrust required, thrust and specific impulse of designed engine were verified.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.298-299
• /
• 2015

수중함에서 전력시스템(PS:Power System)이란 함의 추진시스템 뿐만 아니라 함 내에 모든 부하들의 전력공급을 담당하는 매우 중요한 요소이다. 수중함에 있어 전력시스템의 고장은 안정성에 직결되는 요소이므로 이에 대한 분석과 신뢰성 확보는 필수적이다. 본 논문에서는 수중함의 전력생산부에서부터 부하까지 전력이 공급되는 과정을 전기계통도로 표현하여 이에 대해 고장나무분석을 실시하였으며, 기본구조와 계통 여유율을 고려한 전기적 구조의 고장나무분석을 실시하여 이에 따른 구조변화를 비교한다.

• 한국전기화학회:학술대회논문집
• /
• 2001.10a
• /
• pp.27-27
• /
• 2001

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2005.11a
• /
• pp.121-131
• /
• 2005

For thrust motion of high speed underwater torpedo the special hydro reactive fuels that burns in vapor water and water supply from aboard is used. The main component of this hydro reactive fuel is the powder of active metal (Mg, Al) that can burn in water vapor with large heat generation in the rocket combustion chamber. The thermodynamic analysis of combustion properties of the burning of the particles of these active metal in the vapor water have been carried out. The conception for the possible content variants of the hydro reactive fuels have been discussed using the geometrical and thermodynamic combustion conditions with the basic recommendation for contents of designed hydro reactive fuels in future.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.11
• /
• pp.1697-1705
• /
• 2022

The safety of marine construction workers and marine pollution problems are occurring due to large-scale offshore construction. In particular, underwater construction work in the sea has a higher risk than other work, so it is necessary to apply an unmanned alternative system that considers the safety of the workers. In this paper, the ROV system for offshore construction has been developed for underwater unmanned work. A monitoring system was developed for position control through the control of underwater propellants, pneumatic gripper, and monitoring of underwater work. As a result of the performance evaluation, the underwater movement speed of the ROV was evaluated to be 0.89 m/s, and it was confirmed that the maximum load of the pneumatic gripper was 80 kg. In addition, the network bandwidth required for underwater ROV control and underwater video streaming was evaluated to be more than 300Mbps, wired communication at 92.7 ~ 95.0Mbit/s at 205m, and wireless communication at 78.3 ~ 84.8Mbit/s.