• Title/Summary/Keyword: Deep-Sea

Search Result 1,129, Processing Time 0.031 seconds

Preconditioning Phase for Open Ocean Formation in the Northern Part of Subpolar Front of the East Sea (외양대류에 의한 동해 심층수의 형성 가능성)

  • Lee Chung Il;Cho Kyu Dae;Kim San-Woo;Yun Jong-Hwui;Park Sung-Eun
    • Proceedings of KOSOMES biannual meeting
    • /
    • 2004.11a
    • /
    • pp.117-122
    • /
    • 2004
  • In order to investigate the initial stage of deep water formation between Vladivostok and the subpolar front in the East Sea, the factors, temperature, salinity, dissolved oxygen, measured by multi-ship surveys in 1969 have been used Deep water formation in the East Sea occurs in essentially two different forms: near continent and open ocean formation the position of eddy derived from potential vorticity matches well with that of deep water formation. The vertical and horizontal distributions of potential vorticity, geostrophic current, temperature, salinity and dissolved oxygen give clues for the preconditioning phase of open ocean formation like a doming of isotherm, associated with a cyclonic circulation

  • PDF

A Fundamentals study on Heat Exchanger using Deep Ocean Water: Effects of Corrosion on Heat Transfer Performance (심층수 이용 열교환기 개발을 위한 기초연구: 열교환기 부식이 열교환기 성능에 미치는 영향)

  • Kwon, Young-Chul;Lee, Seok-Hyun;Huh, Cheol;Cho, Meang-Ik;Lee, Chang-Kyung;Kwon, Jeong-Tae
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.11
    • /
    • pp.5377-5384
    • /
    • 2013
  • This paper presents the effects of the tube materials and corrosion on the heat transfer performance of double-tube heat exchangers for the development of heat exchangers using deep sea water. Heat exchangers made of titanium, aluminum. stainless steel, iron, copper, and aluminum with electro-deposition coatings(Carbon black_$15{\mu}m$, Carbon black_$150{\mu}m$) were tested. Also, the heat transfer rate of each heat exchanger was calculated by using EES program. For the acceleration of corrosion by sea water, the temperature of sea water $70^{\circ}C$ and the concentration of salt 3.5% were considered. And the specimens were immersed in sea water during 6 weeks. From the above experiment and analysis, aluminum with electro-deposition coating(Carbon black_$150{\mu}m$) can be considered the most promising candidate for the replacement of titanium heat exchanger.

Preconditioning phase for open ocean formation in the northern part of subpolar front of the East Sea (동해에서 외양대류에 의한 심층수 형성 초기단계의 특성)

  • Lee, Chung-Il;Kim, Dong-Sun;Kim, Sang-Woo;Yun, Jong-Hwui
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.11 no.1 s.22
    • /
    • pp.77-82
    • /
    • 2005
  • In order to investigate the initial stage of deep water formation between Vladivostok and the subpolar front in the East Sea, the factors, temperature, salinity, dissolved oxygen, measured by multi-ship surveys in ]969 have been used. Deep water formation in the .cast Sea occurs in essentially two different forms: near continent and open ocean formation. The position of eddy derived from potential vorticity matches well with that of deep water formation. The vertical and horizontal distributions of potential vorticity, geostrophic current, temperature, salinity and dissolved oxygen give clues for the preconditioning phase qf open ocean formation like a doming of isotherm, associated with a cyclonic circulation.

  • PDF

Risk-based Design of On-board Facility for Lifting System Field Test of Deep-sea Mining System (심해저 광물자원 양광시스템 실증 시험을 위한 위험도 기반 선상 설비 설계)

  • Cho, Su-gil;Park, Sanghyun;Oh, Jaewon;Min, Cheonhong;Kim, Seongsoon;Kim, Hyung-Woo;Yeu, Tae Kyung;Jung, Jung Yeul;Bae, Jaeil;Hong, Sup
    • Journal of Ocean Engineering and Technology
    • /
    • v.30 no.6
    • /
    • pp.526-534
    • /
    • 2016
  • This study had the goal of designing onboard structures for a pre-pilot mining test (PPMT), which is required for the commercialization of the deep-sea mining industry. This PPMT is planned to validate the performance of a hydraulic lifting system and verify the concept of operating through a moon-pool in the east sea, Korea. All of the onboard equipment and facility were designed by KRISO. Because the test was performed at the first development, it is difficult to determine what risk will occur in the facility. Therefore, risk-based design is required in the facility for the PPMT, which includes the facility layout, failure mode and effect analysis (FMEA), and risk reduction plan. All of the expected performances of the lifting system itself and the onboard facilities were qualitatively validated using the risk-based design.

Vector form intrinsic finite-element analysis of static and dynamic behavior of deep-sea flexible pipe

  • Wu, Han;Zeng, Xiaohui;Xiao, Jianyu;Yu, Yang;Dai, Xin;Yu, Jianxing
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.12 no.1
    • /
    • pp.376-386
    • /
    • 2020
  • The aim of this study was to develop a new efficient strategy that uses the Vector form Intrinsic Finite-element (VFIFE) method to conduct the static and dynamic analyses of marine pipes. Nonlinear problems, such as large displacement, small strain, and contact and collision, can be analyzed using a unified calculation process in the VFIFE method according to the fundamental theories of point value description, path element, and reverse motion. This method enables analysis without the need to integrate the stiffness matrix of the structure, because only motion equations of particles established according to Newton's second law are required. These characteristics of the VFIFE facilitate the modeling and computation efficiencies in analyzing the nonlinear dynamic problem of flexible pipe with large deflections. In this study, a three-dimensional (3-D) dynamical model based on 3-D beam element was established according to the VFIFE method. The deep-sea flexible pipe was described by a set of spatial mass particles linked by 3-D beam element. The motion and configuration of the pipe are determined by these spatial particles. Based on this model, a simulation procedure to predict the 3-D dynamical behavior of flexible pipe was developed and verified. It was found that the spatial configuration and static internal force of the mining pipe can be obtained by calculating the stationary state of pipe motion. Using this simulation procedure, an analysis was conducted on the static and dynamic behaviors of the flexible mining pipe based on a 1000-m sea trial system. The results of the analysis proved that the VFIFE method can be efficiently applied to the static and dynamic analyses of marine pipes.

Applying Axiomatic Design to Design Evaluation of a Deep-Sea Manganese Nodule Miner (공리적 설계를 적용한 심해저 망간단괴 집광시스템의 설계평가)

  • Choi, Jong-Su;Hong, Sup;Kim, Hyung-Woo;Yeu, Tae-Kyung;Lee, Tae-Hee
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.13 no.3
    • /
    • pp.246-251
    • /
    • 2008
  • The conceptual design evaluation of Deep-Sea Manganese Nodule Miner(DSNM) based on Axiomatic Design was preformed. Functional Requirements(FRs) in functional domain and Design Parameters(DPs) in physical domain were embodied for the given concept design of DSNM. Interactions between FRs and DPs were sequentially analyzed from the first level hierarchy to the lower level hierarchy. The interactions were expressed as design matrices which showed the dependence or independence between FRs and DPs. The results showed that the design of DSNM was not a coupled one, but a decoupled. Finally, it was conceptually verified that DSNM was a good design satisfying the independence axiom of the Axiomatic Design.

Abnormal Winter Melting of the Arctic Sea Ice Cap Observed by the Spaceborne Passive Microwave Sensors

  • Lee, Seongsuk;Yi, Yu
    • Journal of Astronomy and Space Sciences
    • /
    • v.33 no.4
    • /
    • pp.305-311
    • /
    • 2016
  • The spatial size and variation of Arctic sea ice play an important role in Earth's climate system. These are affected by conditions in the polar atmosphere and Arctic sea temperatures. The Arctic sea ice concentration is calculated from brightness temperature data derived from the Defense Meteorological Satellite program (DMSP) F13 Special Sensor Microwave/Imagers (SSMI) and the DMSP F17 Special Sensor Microwave Imager/Sounder (SSMIS) sensors. Many previous studies point to significant reductions in sea ice and their causes. We investigated the variability of Arctic sea ice using the daily sea ice concentration data from passive microwave observations to identify the sea ice melting regions near the Arctic polar ice cap. We discovered the abnormal melting of the Arctic sea ice near the North Pole during the summer and the winter. This phenomenon is hard to explain only surface air temperature or solar heating as suggested by recent studies. We propose a hypothesis explaining this phenomenon. The heat from the deep sea in Arctic Ocean ridges and/or the hydrothermal vents might be contributing to the melting of Arctic sea ice. This hypothesis could be verified by the observation of warm water column structure below the melting or thinning arctic sea ice through the project such as Coriolis dataset for reanalysis (CORA).