• Title/Summary/Keyword: Heeling angle

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A Study of Real Ship Experiments to Estimate the Heeling Angle of Passenger Type Ship when Turning (여객선형의 선회 중 횡경사 추정에 관한 실선 실험 연구)

  • Kim, Hongbeom;Lee, Yunhyung;Park, Youngsun;Kong, Gilyoung
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.5
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    • pp.497-503
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    • 2018
  • Passenger ships and training ships have a common feature in that they serve many passengers. Thus, safe navigation is very important. During normal sailing, a ship may turn using various types of steering, including maneuvers to avoid collisions with dangerous target. When a ship turns, a heeling angle occurs. If trouble arises during sailing, a dangerous heeling angle may result or a capsizing accident. In this study, the heeling angle during turning was measured through experimentation with two training ships similar to passenger ships. These findings were compared with theoretical formulas for heeling angle when turning. We confirmed that the limit of the maximum heeling angle estimation using heeling angle formula when turning presented in IMO stability criteria. In addition, it was confirmed that the maximum estimated heeling angle can be reached by applying the result calculated in the theoretical formula 1.4 times when turning right and 1.1 times when turning left to reflect sailing speed when of rudder hard over. It is expected that this study will provide basis data for establishing safe operation standards for the prevention of dangerous heeling angles when turning.

Passenger evacuation simulation considering the heeling angle change during sinking

  • Kim, Hyuncheol;Roh, Myung-Il;Han, Soonhung
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.11 no.1
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    • pp.329-343
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    • 2019
  • In order to simulate the evacuation simulation of a ship during a sinking, the slope angle change of the ship must be reflected during the simulation. In this study, the passenger evacuation simulation is implemented by continuously applying the heeling angle change during sinking. To reflect crowd behavior, the human density and the congestion algorithm were developed in this research and the walking speed experiment in the special situation occurring in the inclined ship was conducted. Evacuation simulation was carried out by applying the experimental results and the change of the walking speed according to the heeling angle of the ship. In order to verify the evacuation simulation, test items suggested by International Maritime Organization (IMO) and SAFEGUARD Validation Data Set conducted on a large Ro-PAX ferry (SGVDS 1) which performed real evacuation trial in full-scale ships were performed and the results of simulation were analyzed. Based on hypothetical scenario of when a normal evacuation command is delivered to the passengers of MV SEWOL in time, we predicted and analyzed the evacuation process and the number of casualties.

Optimized Trim and Heeling Adjustment by Using Heuristic Algorithm (휴리스틱 알고리즘을 이용한 트림 및 힐링 각도 조절 최적화)

  • HONG CHUNG You;LEE JIN UK;PARK JE WOONG
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.11a
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    • pp.62-67
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    • 2004
  • Many ships in voyage experience weight and buoyancy distribution change by various reasons such as change of sea water density and waves, weather condition, and consumption of fuel, provisions, etc . The weight and buoyancy distribution change can bring the ships out of allowable trim, heeling angle. In these case, the ships should adjust trim and heeling angle by shifting of liquid cargo or ballasting, deballasting of ballast tanks for recovery of initial state or for a stable voyage. But, if the adjustment is performed incorrectly, ship's safety such as longitudinal strength, intact stability, propeller immersion, wide visibility, minimum forward draft cannot be secured correctly. So it is required that the adjustment of trim and heeling angle should be planned not by human operators but by optimization computer algorithm. To make an optimized plan to adjust trim and heeling angle guaranteeing the ship's safety and quickness of process, Uk! combined mechanical analysis and optimization algorithm. The candidate algorithms for the study were heuristic algorithm, meta-heuristic algorithm and uninformed searching algorithm. These are widely used in various kinds of optimization problems. Among them, heuristic algorithm $A^\ast$ was chosen for its optimality. The $A^\ast$ algorithm is then applied for the study. Three core elements of $A^\ast$ Algorithm consists of node, operator, evaluation function were modified and redefined. And we analyzed the $A^\ast$ algorithm by considering cooperation with loading instrument installed in most ships. Finally, the algorithm has been applied to tanker ship's various conditions such as Normal Ballast Condition, Homo Design Condition, Alternate Loading Condition, Also the test results are compared and discussed to confirm the efficiency and the usefulness of the methodology developed the system.

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A Study on Angle of Heel in Turning using Ship Maneuverability lndices (선박 조종성 지수를 이용한 선회 중 횡경사에 관한 기초연구)

  • Kim, Hong-Beom;Yim, Jeong-Bin
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2019.11a
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    • pp.269-269
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    • 2019
  • The ships are turning for the purpose of collision avoidence and change of course. It is possible that ships have capsizing accident when improper loading of cargo and excessive use rudder angle in turning. It is difficult for navigation officers to recognize the danger of heeling during a turn, because the dynamic state of the ship changes in real time. Thus, in this study, ship's heeling angle was predicted during turning using the maneuverability indices estimated from the ship's autopilot. The maneuverability indices estimated through the Kalman filter of Autopilot is real-time predictable. The turning radius was obtained from the estimated Index of turining ability and calculations of the heeling angle were possible in turning. It is intended to be used as a basic data on the prevention of danger heeling angle during turning.

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Numerical study on aerodynamics of banked wing in ground effect

  • Jia, Qing;Yang, Wei;Yang, Zhigang
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.8 no.2
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    • pp.209-217
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    • 2016
  • Unlike conventional airplane, a WIG craft experiences righting moment and adverse yaw moment in banked turning in ground effect. Numerical simulations are carried out to study the aerodynamics of banked wing in ground effect. Configurations of rectangular wing and delta wing are considered, and performance of endplates and ailerons during banking are also studied. The study shows that righting moment increase nonlinearly with heeling angle, and endplates enhance the righting. The asymmetric aerodynamic distribution along span of wing with heeling angle introduces adverse yaw moment. Heeling in ground effect with small ground clearance increases the vertical aerodynamic force and makes WIG craft climb. Deflections of ailerons introduce lift decrease and a light pitching motion. Delta wing shows advantage in banked turning for smaller righting moment and adverse yaw moment during banking.

Simulation Analysis on Passengers' Normal Evacuation Scenarios Considering the Changes of Heeling Angle during MV Sewol's Sinking (세월호 침몰시의 힐링각변화 조건에서 승객의 정상적인 탈출시나리오에 관한 시뮬레이션 분석)

  • Hwang, Kwang-Il
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.1
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    • pp.47-56
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    • 2015
  • Under the conditions of invested actual changes of heeling angles during MV Sewol's sinking, this study proposes passengers' evacuation scenarios, which are based on the assumption of normal orders of evacuation being given to the passengers, and evaluates using a marine-specialized human evacuation simulation tool. As results, when the heeling angle is set as 0 degree or 30 degree, it is found out that almost every passengers can success to evacuate to the musterstations, even though the evacuation times are different depending on the scenarios and the walking speeds. Meanwhile, when the heeling angle is varied as the Sewol incident, 3.1 %(Scenario Sc-Va which set chutes on port side as evacuation routes), 11.1 %(Sc-Vb, every open decks of port side as evacuation routes) and 20.0 %(Sc-Vc, every open decks of port and AFT sides as evacuation routes) among 476 passengers can successfully reach to the musterstations from their cabins with the condition of average walking speed as 2.04 m/s on flat. And only 0.8 %(Sc-Va), 3.8 %(Sc-Vb) and 10.7 %(Sc-Vc) can success to evacuate with the condition of average walking speed as 1.48 m/s on flat.

Fundamental Research for Escape Guidance System Development of Passenger Ship

  • Ryu, Eun-Gyeong;Yang, Chan-Su;Choi, Jang-Won
    • Journal of Navigation and Port Research
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    • v.41 no.2
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    • pp.39-46
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    • 2017
  • This study represents a fundamental research for a passenger-ship escape guidance system that is a ship-borne agent, and it is for the support of escape decision-making by providing accurate maritime safety information in real time. We conducted a passenger escaping experiment on a training ship, SAEYUDAL, using the situation-aware escape guidance system, which has been developed for on-board application based on products for buildings. It is shown that the system contributes to the shortening of the escape duration and the dispersion of the escaping persons by generating and guiding the safe escape routes which dangerous areas are considered. From the experiment on ship's heeling condition, it is revealed that the heeling angle is linearly related to the escape duration. Therefore, this study shows that the shortening of the escape duration enables a safe and rapid mustering that is the most important process under emergency and appropriate incident responses to minimize loss of lives.

The Effect of The Drift Velocity on The Ship Motion (표류(漂流)를 고려한 선체운동(船體運動))

  • J.H.,Hwang;Y.J.,Kim
    • Bulletin of the Society of Naval Architects of Korea
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    • v.18 no.3
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    • pp.29-38
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    • 1981
  • In general the drift result in ship heeling, thus it seems to be necessary to analyze the ship motion by considering both the drifting and heeling phenomena. In this paper, a drift velocity and a heeling angle are given as prior conditions, and then within the linear potential theory the hydrodynamic coefficients and wave exciting forces and moments are derived for a ship advancing and drifting with constant speeds. And numerical calculations are preformed for a cylindrical body of shiplike cross section at zerp forward velocity. The 2-D hydrodynamic forces and moments of a heeled cylinder are calculated by using the Frank Close-Fit method. These numerical results for the oscillating cylinder without drift velocity have shown better agreements with experimental data than the numerical results of Kobayashi[2]. The motion responses for a drifting cylinder are calculated ignoring the drift velocity effect in the free surface condition. The accuracy of these calculations can not be verified, because the experimental data are not available. Through these numerical calculations to so concluded that drift velocity effects on the body motion are signiffcant.

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A Study on the Effect of Wind Force and Moment Acting on T/S HANNARA (실습선 한나라호에 작용하는 풍압력 및 풍압모우멘트 영향에 관한 연구)

  • Lee, Yun-Sok
    • Journal of Navigation and Port Research
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    • v.31 no.3 s.119
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    • pp.223-228
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    • 2007
  • In recent trends of the enlargement and specialization, container ship, LNCG, PCC and passenger ship which have relatively large hull and superstructure above the water line, are already being operated in the world It is very important information for the safety operation of these vessels to estimate the ship's performance under the specific wind condition while berthing, unberthing or low-speed sailing. In this paper, the effect of wind force and moment acting on the training ship HANNARA is investigated by using the numerical calculations. The results of drift angle and counter rudder angle with the relative wind direction and force, the critical wind velocity with the ratio of wind velocity and ship's speed and maximum heeling angle with the wind velocity are shown The presented results can be applied directly to T/S HANNARA in berthing maneuver and avoiding typhoons, and utilized as an educational materials.