scholarly journals Status and needs for ice tank testing in a changing climate

2021 ◽  
Vol 1201 (1) ◽  
pp. 012060
Author(s):  
P Jochmann ◽  
G Ziemer ◽  
D Myland ◽  
N Reimer ◽  
Q Hisette
Keyword(s):  
First Generation ◽  
Model Tests ◽  
Future Trends ◽  
Century Model ◽  
Testing Methods ◽  
Arctic Regions ◽  
River Elbe ◽  
Offshore Activities ◽  
Ice Model ◽  
Naval Architect

Abstract 150 years ago, the first modern icebreaker in the world was designed by the naval architect Carl Ferdinand Steinhaus and built for purpose of removing ice barriers on the river Elbe in Hamburg, Germany. No model tests were performed at that time. Later, in the first half of the 20th century, “model tests” for ships were carried out in natural ice on lakes. In the 1950th the first-generation ice model basins were put in operation and ice model testing became a standard method in the icebreaker design process. This paper discusses the influence of the economic and environmental development in arctic regions, driven by shipping and offshore activities in environmental changing Arctic Waters, on the ice model basin design, equipment and testing methods. The developments will be presented with examples from The Hamburg Ship Model Basin (HSVA). To complete the overview, an outlook to future trends is attempted.

Ice Model Tests in Context of the Investment Value of an Offshore Vessel

2012 ◽  
Author(s):  
Rüdiger von Bock und Polach ◽  
Vinod Janardanan ◽  
Sören Ehlers
Keyword(s):  
Oil And Gas ◽  
Economic Value ◽  
Model Tests ◽  
Economic Consequences ◽  
Oil And Gas Exploration ◽  
Arctic Regions ◽  
Design Changes ◽  
Hull Structure ◽  
Ice Impacts ◽  
Ice Model

Offshore activities and shipping in Arctic regions increased significantly in the past decade due to fossil resources. These areas hold about 15% of the worlds oil and gas. Exploration or transportation in such harsh Arctic environments possesses additional risks for the crew, the material and the environment. Hence, ships need to be able to handle low temperatures and ice impacts. Ice class certificates issued by classification societies reflect the ships level of ice capability. They are further required to be admitted to ice covered waters or particular regions in seasons with a certain probability of ice occurrence. In most cases, offshore operations are not continued in ice and ships need to transit through ice after abandoning a site upon ice arrival. However, the daily costs of such specialized vessels are high with up to 0.5M$ day that are not reimbursed in downtimes or transit. Therefore, in Northern Arctic regions a higher ice class can significantly enhance the ships workability and therewith its economic value. The lower Polar ice classes, respectively Baltic ice classes, can only be determined analytically with empirically validated formulae for common cargo ships. Other ship types and ships with low L/B ratios are typically required to prove their ice capability through ice model tests. Nevertheless, ice model tests determine only the ice class of the propulsion system, whereas the ice class of the hull structure is determined by calculations. Furthermore, ice model tests are typically conducted towards the end of the design phase where eventual modifications are expensive and potentially threaten the construction schedule of the vessel. Often steel and equipment have already been procured and the manufacturing has begun. This paper presents an iterative procedure of ice model testing and design updates in order to enhance the performance of a particular offshore vessel to meet the requirements for a particular ice class. Thereby, it will be shown how an increase in investment costs for the design changes is compensated by the increasing value of the ships capabilities due to the higher ice class. Furthermore, the drop in value of the ship for the next lower ice class will be indicated as well as the economic consequences should the ship fail to reach the targeted ice class.

Oil Skimming Efficiency of the SOS: Scaling From GeoSim Model Tests to Full Scale Prototype Operations

2012 ◽  
Author(s):  
Günther F. Clauss ◽  
Sascha Kosleck ◽  
Florian Sprenger ◽  
Laura Grüter
Keyword(s):  
Flow Pattern ◽  
Oil Recovery ◽  
Open Water ◽  
Model Tests ◽  
Full Scale ◽  
Polluted Water ◽  
Water Separation ◽  
Weathering Processes ◽  
River Elbe ◽  
Hydrodynamic Effects

The severe ecological and economical aftermath of the 2010 ‘Deepwater Horizon’ catastrophe in the Gulf of Mexico clearly shows the insufficiency of current oil recovery systems which cannot operate in wave heights above 1.5m. To prevent emulsification and weathering processes, it is necessary to skim the oil film off the sea surface shortly after the accident. The autonomous SOS (Sea State-independent Oil Skimming System) developed within the framework of the research project SOS3 features high transit velocities, the capability of operating in rough seas and a massive intake of oil polluted water — and is therefore a unique technology. The oil water separation process of the SOS is purely based on hydrodynamic principles involving vortex evolution and a special flow pattern inside the internal moon pool. These requirements for efficient oil skimming operations depend on various hydrodynamic effects that would imply model testing in compliance with Froude’s and Reynolds’ law simultaneously — a physically impossible condition. Therefore GeoSim model tests with the SOS at model scales of 1:16, 1:25 and 1:36 are conducted with discrete particles of the correct density substituting the oil phase. The tendencies in flow pattern evolution and oil skimming efficiency are compared and extrapolated to full scale. Results from open water tests with the prototype of the SOS in the mouth of river Elbe serve for validation of the extrapolated results.

The Resistance of Ice Breaking Ships Based on Model Tests

2015 ◽  
Author(s):  
Seong-Rak Cho ◽  
Kuk-Jin Kang ◽  
Sungsu Lee
Keyword(s):  
Model Tests ◽  
Design Stage ◽  
Preliminary Design ◽  
Factors Associated ◽  
Preliminary Design Stage ◽  
Level Ice ◽  
Resistance Prediction ◽  
Ice Resistance ◽  
Priority Factor ◽  
Ice Model

The two most important tasks of ice breaking ships are first to secure a sailing route by breaking the thick sea ice and second to sail efficiently herself for purposes of exploration and transportation in the polar seas. The resistance of ice breaking ships is a priority factor at the preliminary design stage; not only must their sailing efficiency be satisfied, but the design of the propulsion system will be directly affected. Therefore, the performance of ice-breaking ships must be accurately calculated and evaluated through the use of model tests in an ice model basin before construction starts. In this paper, a new procedure is developed, based on model tests, to estimate a ship’s ice resistance during continuous icebreaking in level ice. Some of the factors associated with crushing failures are systematically considered in order to correctly estimate her ice-breaking resistance, while the effects of the hull geometry, as reflected in the length, breadth, and draft of ships, are considered in calculating buoyancy and clearing resistance. Multiple regression analysis is calculated with each ice resistance component. This study is intended to contribute to the improvement of the techniques for ice resistance prediction with ice breaking ships.

Panel Discussion on the Education of Engineers for the Ocean Industry: Future Trends

1977 ◽  
Vol 14 (03) ◽  
pp. 223-233
Author(s):  
T. Francis Ogilvie ◽  
I. Dyer ◽  
C. N. Payne
Keyword(s):  
Engineering Education ◽  
Panel Discussion ◽  
Future Trends ◽  
Ocean Engineering ◽  
Marine Engineer ◽  
Points Of View ◽  
Traditional Roles ◽  
Naval Architect

The traditional roles of the naval architect and marine engineer are expanding into the broad multidisciplinary field of ocean engineering. Education for this field—the problems, methods, and prospects—are explored in this paper, which comprises the points of view of three authorities in the field.

On the Scalability of Model-Scale Ice Experiments

2015 ◽  
Vol 137 (5) ◽  
Author(s):  
Rüdiger U. Franz von Bock und Polach ◽  
Sören Ehlers
Keyword(s):  
Mechanical Properties ◽  
Sea Ice ◽  
State Of The Art ◽  
Model Tests ◽  
Qualitative Assessment ◽  
Model Scale ◽  
Research Findings ◽  
Ice Model

Ice model tests are a frequently used mean to assess and predict the performance of ships and structures in ice. The model ice composition is adjusted to comply with Froude and Cauchy similitude. Recent research indicates that the internal mechanics of Aalto model-scale ice and sea ice differ significantly. This consequently limits the scalability and challenges state-of-the-art scaling procedures. This paper presents a qualitative assessment on selected topics to assess the differences between model-scale ice and sea ice and the influence of related experiments on determined mechanical properties. Furthermore, existing scaling approaches are discussed in context of recent research findings.

scholarly journals Mid-Infrared Waveguides: A Perspective

2016 ◽  
Vol 70 (10) ◽  
pp. 1625-1638 ◽  
Author(s):  
Thomas Schädle ◽  
Boris Mizaikoff
Keyword(s):  
Optical Fibers ◽  
First Generation ◽  
Classification Scheme ◽  
State Of The Art ◽  
Third Generation ◽  
Future Trends ◽  
Mid Infrared ◽  
Mir Spectroscopy ◽  
Sensing Systems ◽  
Infrared Waveguides

Significant advancements in waveguide technology in the mid-infrared (MIR) regime during recent decades have assisted in establishing MIR spectroscopic and sensing technologies as a routine tool among nondestructive analytical methods. In this review, the evolution of MIR waveguides along with state-of-the-art technologies facilitating next-generation MIR chem/bio sensors will be discussed introducing a classification scheme defining three “generations” of MIR waveguides: (1) conventional internal reflection elements as “first generation” waveguides; (2) MIR-transparent optical fibers as “second generation” waveguides; and most recently introduced(3) thin-film structures as “third generation” waveguides. Selected application examples for these each waveguide category along with future trends will highlight utility and perspectives for waveguide-based MIR spectroscopy and sensing systems.

Different Ways of Modeling Ice Drift Scenarios in Basin Tests

2013 ◽  
Author(s):  
Andrea Haase ◽  
Peter Jochmann
Keyword(s):  
Sea Ice ◽  
Relative Motion ◽  
Development Project ◽  
Model Tests ◽  
Contact Forces ◽  
Second Phase ◽  
Offshore Structure ◽  
Ice Drift ◽  
Ice Field ◽  
Ice Model

One known scenario from full scale sea ice investigations is a drifting managed ice field. This ice field may be driven by winds or currents or both and may eventually hit a vessel or an offshore structure. In case of a moving vessel the relative motion between vessel and ice may be determined by the vessels direction of motion or even its ambition to hold position against the drifting ice. All the above described scenarios deal with relative motions between several bodies. Along with the relative motion come the contact forces between the interacting bodies and last but not least the question of the failure of either of the bodies. As ice model tests are in general state of the art procedures to investigate the behavior of a vessel and the related loads in sea ice the question of how to model drift scenarios is of relevance here. Typically in ice model tests a drifting managed ice field is simulated by moving a model ship through a resting ice field. This paper addresses the differences in modeling the ice drift as described above and when moving the floes against a stationary vessel. For this purpose ice model tests of each kind are investigated and theoretical efforts are made to enlighten the topic. Also it is distinguished between the vessel being driven by its own propulsion system or by an external force. In summer 2011 and 2012 a comprehensive set of ice model tests was performed in the large ice tank of the Hamburg Ship Model Basin (HSVA). The tests are related to the research and development project DYPIC — Dynamic Positioning in Ice. Within the project two phases of model tests have been performed. The first phase has been documented and presented in [1] while the second phase is presented in [2]. The model setups described and analyzed in this paper all relate to tests performed within the scope of DYPIC.

Development of a Component-Based Scaling System for Ship-Ice Model Tests

1992 ◽  
Vol 36 (01) ◽  
pp. 77-87
Author(s):  
D. B. Colbourne ◽  
J. H. Lever
Keyword(s):  
Scaling Law ◽  
Model Tests ◽  
Experimental Procedure ◽  
Independent Components ◽  
Comprehensive Literature Review ◽  
Full Form ◽  
Scaling Parameters ◽  
Form Model ◽  
Ice Resistance ◽  
Ice Model

This paper presents the development and verification of a method for conducting and scaling ice resistance model tests based on division of the total resistance into three components. It is shown that each of these components is subject to a separate scaling law. A comprehensive literature review traces development of the concept of independent components in icebreaking resistance and covers development of nondimensional scaling parameters. A system of analysis and presentation is developed based on nondimensional parameters unique to each of the identified components. A set of experiments was carried out on a highly simplified full form model to verify the proposed experimental procedure. Data from these experiments demonstrate the excellent data collapse which can be achieved using the developed nondimensional presentation.

Study on Resistance Performance of Ice-Breaking Tanker According to Ship’s Length

2018 ◽  
Author(s):  
Seong-Rak Cho ◽  
Jinho Jang ◽  
Cheol-Hee Kim ◽  
Eun-Jin Oh ◽  
Kuk-Jin Kang ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Open Water ◽  
Model Tests ◽  
Ice Friction ◽  
Resistance Performance ◽  
Ice Model ◽  
Resistance Component

In this paper, ice model tests with different lengths of parallel middle-body were conducted to estimate accurate resistance performance of ice-breaking merchant vessels. Totally, three model ships were manufactured: The standard vessel is 90,000 DWT tanker to transport oil in the ARC7 condition, and two vessels have only different lengths of parallel middle-ship compared to the standard vessel. Ice breaking, ice friction, ice buoyancy, and open-water resistances were classified and measured in experiments, and each resistance component according to change of ship’s length is analyzed. In addition, the resistance formula of ice-breaking tanker is developed by a regression analysis.

Methodology to Investigate the Icebreaking Process of Ships With Non-Typical Icebreaking Bow Shapes

2020 ◽  
Author(s):  
Quentin Hisette ◽  
Daniela Myland
Keyword(s):  
Ice Sheets ◽  
Relevant Information ◽  
Model Tests ◽  
Interaction Process ◽  
Analysis Procedure ◽  
Load Cells ◽  
Level Ice ◽  
Ice Resistance ◽  
Different Thickness ◽  
Ice Model

Abstract For non-typical icebreaking ships the hull-ice interaction process in level ice comprises a combination of many different phenomena which is difficult to be described by existing straightforward approaches. In order to gain knowledge about the level ice resistance of such non-typical hull shapes for operation in ice, a methodology is developed and presented to identify and evaluate the level ice resistance as well as its distribution along the hull of ships with non-typical icebreaking bow shapes with high stem and/or small waterline angles. For this purpose, one ship model has been manufactured and instrumented with several multi-component load cells in the bow region of the waterline as well as with one large six-component load scale between the bow and the stern. Performing resistance model tests at several loading conditions, in model ice sheets of different thickness and at multiple speed values allows obtaining relevant information to meet the goals of the study. The paper focuses on the methodology used for the ice model tests and its analysis. Instrumentation of the model is fully described, together with an overview of the testing matrix and model test observations. Analysis procedure is described in details and applied on a representative test run of the campaign.

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