Effect of Coal Loading Conditions on Elastic Behavior of Large-Scale Floating Transshipment Station (LFTS)

2017 ◽  
Author(s):  
Hiroaki Eto ◽  
Chiaki Sato ◽  
Koichi Masuda ◽  
Tomoki Ikoma ◽  
Mitsuru Kubota ◽  
...  
Keyword(s):  
Large Scale ◽  
Static Stability ◽  
Asia Pacific ◽  
Elastic Behavior ◽  
Linear Potential ◽  
Loading Conditions ◽  
East Kalimantan ◽  
Sea Bed ◽  
Bulk Carriers ◽  
Linear Potential Theory

Japan imports coal from Indonesia, the main coal supplier in the Asia-Pacific region. Effective and efficient movement of coal down the Markham River in East Kalimantan, Indonesia, and onto bulk carriers is challenging because the river is shallow and generally cannot accommodate bulk carriers. The primary transportation system comprises small barges that are shuttled back and forth between the inland barge ports along the river and bulk carriers offshore. This system is very time-consuming. This paper proposes a large-scale floating coal transshipment station (LFTS) for loading, storing, and offloading coal. It will act as a relay base for barges and bulk carriers. Installing an LFTS offshore from East Kalimantan is expected to improve coal transport productivity. The proposed LFTS can store 5 times the capacity of one bulk carrier and can accommodate 2 bulk carriers at the same time during offloading. The LFTS is compartmentalized by bulkheads to segregate coal according to quality. This paper discusses LFTS static stability and its elastic deformation characteristics during coal loading operations. In this study, linear potential theory and the finite element method (FEM) were used to analyze the LFTS static hydroelastic motion. Due to the compartments, coal loading conditions can vary significantly and affect the local static deflection, so we modeled the overall deformation and rigidity under various operational scenarios. The results were compared to the allowable material stress to identify conditions that will produce material failure. Moreover, we evaluated operation in the shallow Kalimantan River, since the weight of loaded coal deepens the LFTS draft, reducing the clearance between the LFTS and sea bed. We found that this reduced clearance and large added mass impact the natural frequency of the LFTS.

Fundamental Study on Elastic Behavior of Large-Scale Floating Coal Stockyard

2016 ◽  
Author(s):  
Hiroaki Eto ◽  
Chiaki Sato ◽  
Koichi Masuda ◽  
Tomoki Ikoma ◽  
Tomoyuki Kishida ◽  
...  
Keyword(s):  
Mass Distribution ◽  
Large Scale ◽  
Asia Pacific ◽  
Elastic Behavior ◽  
Loading Conditions ◽  
Floating Structure ◽  
Fundamental Study ◽  
Local Rigidity ◽  
East Kalimantan ◽  
The Impact

This paper proposes a large-scale floating coal stockyard (LFCS) and discusses its elastic behavior. Indonesia has recently become the main country supplying coal in the Asia-Pacific region. However, there is concern that export to Japan will decrease as coal demand increases. Therefore, the trend of coal transport in Indonesia is a very important matter in ensuring the continued stable import of coal to Japan. It is difficult for bulk carriers to traverse the shallow terrain of the seabed of the Markham River in East Kalimantan to reach coastal areas. Additionally, an LFCS can be operated as a relay base for barges, and large coal carriers have been proposed for use in offshore areas. The LFCS is capable of loading, storing, and offloading coal. Installing an LFCS offshore Kalimantan is expected to improve coal transport productivity in the region. Under such circumstances, the design plan proposed in this paper can simultaneously perform independent loading and unloading without interference. The partial mass distribution and local rigidity of the LFCS varies depending on the coal loading conditions. In addition, because the structure has a planar shape, the response of the LFCS showed elastic behavior. Design example of such a huge floating structure with the great difference of the displacement is unparalleled, it is very important to clarify a design fundamental subject. The objectives of this study are to provide a preliminary LFCS design and investigate the impact of varying the mass distribution and local rigidity on not only the distribution of the distortion and internal stress but also on the dynamic hydroelastic motion of the LFCS when it is impacted by waves. Therefore, the wave response of the LFCS was analyzed under different loading conditions.

Effect of Coal Loading Conditions on Structural Characteristics of LFTS

2019 ◽  
Author(s):  
Hiroaki Eto ◽  
Koji Iizuka ◽  
Ryo Nishigochi ◽  
Tomoki Ikoma ◽  
Yasuhiro Aida ◽  
...  
Keyword(s):  
Stress Concentration ◽  
Loading Condition ◽  
Local Stress ◽  
Asia Pacific ◽  
Linear Potential ◽  
Detailed Model ◽  
Local Stress Concentration ◽  
East Kalimantan ◽  
Wave Response ◽  
Bulk Carriers

Abstract Indonesia is a main country supplying coal in the Asia-Pacific region, it is important to ensure a stable coal supply to Japan. Because the topography of the seabed near East Kalimantan Island, Indonesia’s main coal production area, is shallow, it is difficult for bulk carriers to reach the coast. Therefore, Large-Scale Floating Coal Transshipment Station (LFTS) was proposed, which will be used as a relay base between coal-barging barges from land and bulk carriers offshore. Installing an LFTS offshore from East Kalimantan is expected to improve coal transport productivity. LFTS can store coal equivalent to five times the capacity of one bulk carrier (total 500,000T), and can accommodate 2 bulk carriers at the same time during offloading. The scale of LFTS is 590m × 160m. The LFTS has a flat spread and the elastic behavior becomes the dominant Structure. The upper part of the LFTS is different rigidity partly because the partition wall to be loaded by dividing the coal into each quality is provided. Loaded coal not only changes the draft of the LFTS but also greatly deforms the LFTS and is expected to cause local stress concentration on the structural members. Therefore, this paper investigates wave response characteristics and stress characteristics with the coal loading of the LFTS, and then evaluation of structural strength by limit state design method. In this study, linear potential theory and the finite element method (FEM) were used to analyze the static hydroelastic motion under various coal loading condition and wave response of LFTS. And, to grasp the local stress concentration occurring inside the LFTS by using the response results, a detailed model modeling a complicated internal structure was prepared. Zooming analysis which is a method of giving the deformation result by the whole model of LFTS as forced displacement to the local detailed model was carried out. As a result, depending on the coal loading condition and wave conditions, it became clear that LFTS will be in a tough situation.

A Prediction Method of Hydroelastic Motion of Aircushion Type Floating Structures Considering With Draft Effect Into Hydrodynamic Forces

2008 ◽  
Author(s):  
Tomoki Ikoma ◽  
Masato Kobayashi ◽  
Koichi Masuda ◽  
Chang-Kyu Rheem ◽  
Hisaaki Maeda
Keyword(s):  
Potential Theory ◽  
Water Waves ◽  
Large Scale ◽  
Prediction Method ◽  
Linear Potential ◽  
Wave Loads ◽  
Floating Structure ◽  
Model Experiments ◽  
Very Large Floating Structure ◽  
Linear Potential Theory

An aircushion type floating structure can prevent to enlarge the wave drifting force restraining the hydroelastic response of it in water waves. The floating structure should be large scale to incident waves in order to make the best use of such advantages, i.e. it is a very large floating structure. The linear potential theory is useful to easily handle the wave force etc. on the aircushion type floating structure theoretically because it is predicted that its theory can give good results of behaviors of water elevation within aircushions and pressure and of wave loads on the structure qualitatively. The authors have confirmed from our past model experiments that non-linear effect does not always increase but for some exceptions. A prediction method of hydroelastic responses for the aircushion type very large floating structure by using the three-dimensional linear potential theory is shown in this paper. The validity of the method is proven and the application of the method is investigated by comparing the theoretical results with the results of the past model experiments.

A Fundamental Study on Plastic Strain Accompanying Deformation in Large-Scale Floating Coal Transshipment Station

2020 ◽  
Author(s):  
Ryo Nishigochi ◽  
Hiroaki Eto ◽  
Koji Iizuka ◽  
Tomoki Ikoma ◽  
Yasuhiro Aida ◽  
...  
Keyword(s):  
Plastic Strain ◽  
Loading Condition ◽  
Large Scale ◽  
Asia Pacific ◽  
Floating Body ◽  
Deformation Analysis ◽  
Wave Load ◽  
Oscillation Analysis ◽  
Entire Structure ◽  
Bulk Carriers

Abstract Indonesia is the main country supplying coal in the Asia-Pacific region, and in order to secure a stable supply of coal to neighboring countries, efficient coal transportation is required. East Kalimantan Island in Indonesia is the main coal-producing area, but the sea around the island is very shallow and bulk carriers for transporting coal cannot approach the coast. And then, Large-scale Floating Transposition Station for Loading Coal (hereafter LFTS) was proposed, which will be used as a transposition station between small coal barge coming down the river and bulk carriers that stays offshore. LFTS has a two-dimensional extent, and because the bulkheads for separating coal according to quality are installed on the floating body, the rigidity is partially different, and the draft also changes greatly according to the coal loading condition. In this way, LFTS has different characteristics from Mega-Float, which was built in Japan in the late 1990s with the aim of realizing a floating airport, so it is important to clarify its structural characteristics. In order to grasp the stress distribution acting on the structural member in consideration of the influence of the interaction between the overall deformation and the local deformation of LFTS, an analysis in which the entire structure is modeled in detail is desired. However, because members such as the internal bulkheads are arranged in a complicated manner in LFTS, a model in which the entire structure is modeled in detail requires enormous calculation costs in both capacity and time, it is difficult to perform the analysis. In existing research, various models have been studied, but there remains a problem in setting boundary conditions that reproduce the interaction between global and local deformations. And then, in this paper, a new modeling method of LFTS that can be analyzed efficiently was proposed. And the occurrence of stress concentration in the structural members of the LFTS was identified by systematically changing the external force conditions such as the coal loading condition and wave load assumed during the operation of the LFTS, and performing LFTS oscillation analysis and stress deformation analysis. Furthermore, the occurrence of plastic strain due to large deformation was investigated. The stiffening method that efficiently suppresses the occurrence of plastic strain was studied for the locations where the plastic strain was identified by the above analysis. These results demonstrate the importance of modeling large floating structures with complex structures.

A Fundamental Study on Motion Characteristics of the Large-Scale Floating Coal Transshipment Station by Elastic Mooring Lines

2020 ◽  
Author(s):  
Hiroaki Eto ◽  
Ryo Sekiguchi ◽  
Hitomi Kashima ◽  
Tomoki Ikoma ◽  
Yasuhiro Aida ◽  
...  
Keyword(s):  
Large Scale ◽  
Line Tension ◽  
Asia Pacific ◽  
Floating Body ◽  
Mooring Line ◽  
Mooring System ◽  
Mooring Lines ◽  
Fundamental Study ◽  
Bulk Carriers ◽  
Motion Characteristics

Abstract This paper describes the motion characteristics and cargo handling efficiency of the Large-Scale Floating Coal Transshipment Station (LFTS). Indonesia is the main country supplying coal in the Asia-Pacific region, it is important to ensure stable coal supply to Japan. Because the topography of the seabed near East Kalimantan Island, Indonesia’s main coal production area, is shallow, it is difficult for bulk carriers to reach the coast. And then, Large-scale Floating Transposition Station for Loading Coal (hereafter LFTS) was proposed, which will be used as a transposition station between small coal barge coming down the river and bulk carriers stay offshore. By installing LFTS, improvement of coal transport efficiency is expected. As a previous study, the motion characteristics of LFTS using a catenary chain in its mooring system were grasped. However, LFTS can carry up to 500,000 tons of coal, and the draft of LFTS tends to change greatly depending on the coal loading conditions. Besides, the tidal difference in the sea area where the LFTS is installed is about 2 m, and the mounting position of the mooring system on the LFTS side moves up and down by about 10 m at maximum due to changes in the draft and tidal differences. For this reason, when the mounting position of the mooring system is in the lowest state, the mooring line is loosened and the horizontal force is reduced, and it is considered that sufficient restraining force is not exhibited. And, when the mounting position of the mooring system becomes high, the mooring line tension increases and the mooring line may break in some cases. Therefore, in this study, an attempt was made to use an elastic mooring line as a mooring system for LFTS. An elastic mooring line is a mooring line that incorporates a highly stretchable material between mooring lines that connect anchors and floating body. Even if the mooring line attached to the LFTS moves up and down, an appropriate tension always acts on the elastic mooring line, and it can be expected to suppress the oscillation of the floating body and prevent the mooring line from breaking due to excessive tension. However, elastic mooring lines are mainly used for mooring small structures such as piers and aquaculture facilities, but there are no examples where these mooring lines have been applied to structures over 500m like LFTS. Therefore, elastic mooring lines are adopted for the mooring system of LFTS, systematically calculated according to various setting conditions of elastic mooring lines, and it is grasped whether elastic mooring lines can be applied to LFTS, and the motion characteristics of LFTS moored by elastic mooring lines was also grasped.

Simulation of Multiliquid-Layer Sloshing With Vessel Motion by Using Moving Particle Semi-Implicit Method

2015 ◽  
Vol 137 (5) ◽  
Author(s):  
Kyung Sung Kim ◽  
Moo-Hyun Kim ◽  
Jong-Chun Park
Keyword(s):  
Gas Production ◽  
Particle Simulation ◽  
Small Scale ◽  
Linear Potential ◽  
Operational Effectiveness ◽  
Mps Method ◽  
Moving Particle ◽  
Vessel Motion ◽  
Linear Potential Theory ◽  
Oil Gas

For oil/gas production/processing platforms, multiple liquid layers can exist and their respective sloshing motions can also affect operational effectiveness or platform performance. To numerically simulate those problems, a new multiliquid moving particle simulation (MPS) method is developed. In particular, to better simulate the relevant physics, robust self-buoyancy model, interface searching model, and surface-tension model are developed. The developed multiliquid MPS method is validated by comparisons against experiment in which three-liquid-sloshing experiment and the corresponding linear potential theory are given. The validated multiliquid MPS program is subsequently coupled with a vessel-motion program in time domain to investigate their dynamic-coupling effects. In case of multiple liquid layers, there exists a variety of sloshing natural frequencies for respective interfaces, so the relevant physics can be much more complicated compared with the single-liquid-tank case. The simulation program can also reproduce the detailed small-scale interface phenomenon called Kelvin–Helmholtz instability. The numerical simulations also show that properly designed liquid cargo tank can also function as a beneficial antirolling device.

scholarly journals Synoptic Control over Orographic Precipitation Distributions during the Olympics Mountains Experiment (OLYMPEX)

2018 ◽  
Vol 146 (4) ◽  
pp. 1023-1044 ◽  
Author(s):  
David J. Purnell ◽  
Daniel J. Kirshbaum
Keyword(s):  
Numerical Simulations ◽  
Physical Interpretation ◽  
Large Scale ◽  
Local Development ◽  
Moisture Flux ◽  
Heavy Precipitation ◽  
Static Stability ◽  
Orographic Precipitation ◽  
Areal Extent ◽  
Precipitation Enhancement

The synoptic controls on orographic precipitation during the Olympics Mountains Experiment (OLYMPEX) are investigated using observations and numerical simulations. Observational precipitation retrievals for six warm-frontal (WF), six warm-sector (WS), and six postfrontal (PF) periods indicate that heavy precipitation occurred in both WF and WS periods, but the latter saw larger orographic enhancements. Such enhancements extended well upstream of the terrain in WF periods but were focused over the windward slopes in both PF and WS periods. Quasi-idealized simulations, constrained by OLYMPEX data, reproduce the key synoptic sensitivities of the OLYMPEX precipitation distributions and thus facilitate physical interpretation. These sensitivities are largely explained by three upstream parameters: the large-scale precipitation rate [Formula: see text], the impinging horizontal moisture flux I, and the low-level static stability. Both WF and WS events exhibit large [Formula: see text] and I, and thus, heavy orographic precipitation, which is greatly enhanced in amplitude and areal extent by the seeder–feeder process. However, the stronger stability of the WF periods, particularly within the frontal inversion (even when it lies above crest level), causes their precipitation enhancement to weaken and shift upstream. In contrast, the small [Formula: see text] and I, larger static stability, and absence of stratiform feeder clouds in the nominally unsaturated and convective PF events yield much lighter time- and area-averaged precipitation. Modest enhancements still occur over the windward slopes due to the local development and invigoration of shallow convective showers.

scholarly journals POSITIONS OF STATES OF THE ASIA-PACIFIC REGION REGARDING THE ADOPTION OF RESOLUTIONS ON INTERNATIONAL INFORMATION SECURITY ISSUES WITHIN THE FRAMES OF THE UN

2019 ◽  
pp. 13-26
Author(s):  
Mykola Ryzhkov ◽  
Anastasiia Siabro
Keyword(s):  
Information Security ◽  
International Development ◽  
Information Technologies ◽  
Large Scale ◽  
New Technologies ◽  
Technological Development ◽  
Security System ◽  
Asia Pacific ◽  
Security Issues ◽  
The World

Achievements in the sphere of automatization and telecommunication are an essential component of transformation of the international peace and security system. This article presents, that consequences of changes are of a dual character. On the one hand, new technologies are becoming an important component of society modernization strategies in developing countries, on the other hand, they can be used for armament modernization or creation of new means of confrontation in modern international relations. APR countries face the most relevant issue of information technologies usage. The article deals with the process of discussion of new challenges and threats to international security, emerging as a result of development and large-scale implementation of information-communication technologies. Positions of states regarding the adoption of resolution in the sphere of international information security were studied through examples of Japan, India, and China. It is proved in the article, that information technologies have become an important component of the security system in the world. Technologies usage may lead to steady international development as well as to information arms race. That is why working out a common position on international information security issues is of crucial importance. It is within the framework of the UN, that different states of the world are given an opportunity to express their visions of the problem of international information security and work out common approaches to its solution. The article shows, that states’ positions have similar as well as different features. For instance, all states express concern regarding possible limitation of technology transfer for the establishment of a more controlled international political environment. But states’ positions have major differences as to mechanisms of information security provision. Thus, Japan and India strive to achieve a balanced system of international information security, which should at the same time have preventive mechanisms against the emergence of threats in the information and science and technology spheres and guarantee continuation of scientific-technological development, which is a crucial component of development and modernization strategies in many countries of the world. China came forward with position of strong regulation of international information security issues and suggested framing of corresponding regulations of the states’ conduct in the cyberspace.

scholarly journals Проблемы обеспечения несмещаемости груза при перевозках зерна навалом на универсальных судах

2020 ◽  
Author(s):  
M.A. Moskalenko ◽  
T.E. Malikova ◽  
S.M. Zatepyakin ◽  
I.B. Druz
Keyword(s):  
Free Surface ◽  
Scale Effect ◽  
Large Scale ◽  
Cost Effective ◽  
Loss Of Stability ◽  
Maritime Industry ◽  
Food Trade ◽  
Bulk Carriers ◽  
Grain Bulk ◽  
Freight Market

Морская отрасль является важнейшим звеном в международной торговле, так как морские суда представляют собой наиболее рентабельный способ доставки больших партий массовых грузов на значительные расстояния. Современная логистика перевозок массовых навалочных грузов идет по пути увеличения судовых партий и как следствие, за счет экономии издержек на эффекте масштаба последние годы произошел существенный рост размеров универсальных судов. На универсальных судах, за счет роста торговли продовольствием и сужения фрахтового рынка, в последние годы стали активно перевозиться зерновые навалочные грузы. Известно, что смещение навалочных грузов было связано с большими рисками опрокидывания от потери остойчивости для балкеров, где от потери остойчивости происходит более 46 процентов всех серьезных аварийных случаев. Проблема обеспечения остойчивости становится еще более актуальной при перевозке зерновых навалочных грузов, имеющих усадку примерно в два процента от своего объема, за счет чего во время рейса всегда образуются пустоты в трюмах между свободной поверхностью груза и палубой. Предполагается, что при максимально возможном смещении зерна его свободная поверхность образует с горизонталью углы в 15 и 25 градусов для заполненных и соответственно незаполненных отсеков. Для универсальных судов риски потери остойчивости от смещения груза при перевозках зерна, за счет масштабного эффекта большой удельной погрузочной кубатуры трюмов и высоты борта возрастают многократно.The Maritime industry is an important link in international trade because sea vessels are the most cost-effective way to deliver large quantities of bulk cargo over long distances. Modern transportation of cargo in bulk is on the path of increasing of shiploads and as a result, due to effective on scale effect, there has been a significant increase in the size of universal vessels in recent years. Grain bulk cargo has been actively transported on universal vessels in recent years due to the growth of food trade and the segmentation of the freight market. It is known fact that the displacement of bulk cargo in the vessel holds was associated with high risks of overturning from loss of stability for bulk carriers. More than 46 percent of all serious accidents occur from loss of stability. The problem of ensuring stability becomes even more urgent when transporting grain bulk cargo, which has a shrinkage of about two percent of its volume, which is a reason of free surface between the cargo and the deck inside of vessel holds. It is assumed that at the maximum possible displacement of the grain, its free surface forms angles of 15 and 25 degrees with the horizontal for filled and unfilled compartments, respectively. For multipurpose universal vessels, the risks of loss of stability during grain transportation due to cargo displacement and because of the large-scale effect of the large loading cubic capacity of the holds and the height of the side, increase many times.

scholarly journals PEMETAAN DAN ANALISA KONFLIK ANTARA MASYARAKAT DESA MENAMANG KIRI DAN PT SURYA HUTANI JAYA KABUPATEN KUTAI KARTANEGARA KALIMANTAN TIMUR

2020 ◽  
Vol 2 (4) ◽  
pp. 420-433
Author(s):  
Naldi Gantika
Keyword(s):  
Supply Chain ◽  
Asia Pacific ◽  
Plantation Forest ◽  
East Kalimantan ◽  
The People ◽  
Forestry Sector ◽  
Work Area ◽  
High Conservation ◽  
Conservation Values ◽  
Mediation Processes

The urge for a peaceful and fair settlement of forestry conflicts also encourages business actors in the Indonesian forestry sector to develop conflict resolution mechanisms through dialogue and mediation processes through both mandatory (mandatory) and voluntary (voluntary) mechanisms. The commitment to apply the principle of FPIC (Free, Prior and Informed Consent) or free consent without coercion along its industrial supply chain (Supply Chain) has been declared by plantation companies under the banner of the APP (Asian Pulp and Paper) or Sinar Mas forestry (SMF) group and the APRIL group (Asia Pacific Resources International Limited). Not only that, the commitment to maintaining High Conservation Values ​​contained in the company's work area was also expressed by the two major groups of players in the plantation forest industry in Indonesia. This condition has created opportunities for improved access and relations between the conflicting parties. In East Kalimantan, Conflict Mapping and Analysis was carried out in Menamang Kiri Village, Muara Kaman District, Kutai Kertanegara Regency. In the spatial mapping analysis that was carried out, part of the village of Menamang Kiri was within the concession of PT Surya Hutani Jaya (PT SRH), a wood supplier to APP. Mapping and Conflict Analysis is focused on extracting information related to governance and land management by PT SRH and the people of Menamang Kiri Village, conflicts or potential conflicts that arise and the parties involved, the perceptions of each party related to differences in interests, and policy analysis.

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