Measuring Ice Loading on Podded Propellers Systems

2003 ◽  
Author(s):  
Ayhan Akıntu¨rk ◽  
Stephen Jones ◽  
Corwyn Moores ◽  
John Bell
Keyword(s):  
Research Council ◽  
International Association ◽  
National Research Council ◽  
Experimental System ◽  
Propeller Shaft ◽  
Propulsion Systems ◽  
Lack Of Information ◽  
Ice Loads ◽  
Arctic Navigation ◽  
Thrust And Torque

Currently, work is ongoing to update all of the regulations governing the design of vessels for arctic navigation including the propulsion systems by the International Association of Classification Societies. However, there is a lack of information as to the loads occurring on podded propeller systems operating in ice. Hence, this study aims to close the knowledge gap for this type of propulsion systems. This paper describes the experimental setup designed and built at the National Research Council of Canada Institute for Marine Dynamics (NRC-IMD), for measuring ice loads on such a system. The experimental system is designed to measure the loads on three levels: 1– loads on an individual blade (six components), 2– loads on the propeller shaft (thrust and torque) and, the fore and aft bearings which support the propeller shaft (six components), 3– global forces and moments on the (propeller + pod + strut) system (six components).

Ice Loads on Azimuthing Podded Propulsors

2004 ◽  
Author(s):  
Ayhan Akinturk ◽  
Stephen J. Jones ◽  
Dale Duffy ◽  
Barbara Rowell
Keyword(s):  
Shear Strength ◽  
Flexural Strength ◽  
Ice Sheets ◽  
Experimental System ◽  
Experimental Setup ◽  
Propeller Shaft ◽  
Time Intervals ◽  
Ice Loads ◽  
Propulsion Unit ◽  
Initial Results

The paper describes the experimental setup and presents some of the results obtained. The experimental system is designed and built to measure the loads on the blade, on the propeller shaft bearings, on the shaft, and on the whole propulsion unit (global loads). Experiments have been conducted at various headings form 0° to 180°, thrust directions (aft or forward), and advance coefficients. In the experiments, ice sheets of 60 mm thickness were used. Target flexural strength of the ice sheets was 60 kPa at the start of the experiments. During the course of the experiments, thickness, flexural, compressive and shear strength values of the ice sheets were sampled at certain time intervals in order to record the variations in the ice properties. Initial results suggest that there was an increase of the loads exerted on the podded system due to ice. The increase varies at different azimuth angles and advance velocities.

scholarly journals Exigências nutricionais de cálcio para vacas leiteiras na microrregião de Sousa-PB a partir do uso de aplicativo para smartphone

2019 ◽  
Vol 1 (47) ◽  
pp. 181
Author(s):  
Gilderlândio Pinheiro Rodrigues ◽  
Beatriz Dantas Fernandes ◽  
Jéssica Monique Dos Santos Lima ◽  
Bismark Alves Da Silva ◽  
Daniel Cézar Da Silva ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Technological Innovation ◽  
Rural Areas ◽  
Research Council ◽  
National Research Council ◽  
Nutritional Requirements ◽  
Nutritional Management ◽  
Lactating Cows ◽  
Lack Of Information ◽  
Java Platform

<p class="Default">Technological innovation has had a remarkable rise and its use in rural areas has become a subdisidiary method for both producers and professionals in the agrarian area. In dairy cattle, there is a lack of information about nutritional management. The supply of minerals is inadequate and it does not meet the requirements of animals often. The objective of this study was to develop an application to estimate the nutritional requirements of calcium for dairy cows and to help producers to provide adequate amounts of this mineral. The application was created from the Java platform, using recommendations from the National Research Council (NRC), with calculation of requirements for maintenance of lactating and non-lactating cows, females in growth, gestation. The application enables the filling of data from animal characterization to the type and quantity of concentrate and forage provided. After filling the data the application will generate the result informing whether the cow in lactation has a deficit, surplus or if it is receiving adequate amounts of the mineral. It also demonstrates the amount of calcium that should be increased or decreased, according to the needs of each animal. Using the bovine calcium application, producers will provide an appropriate supplement, reducing unnecessary costs and increasing milk production.</p>

Investigating acoustics and wave behaviour in cross-laminated timber panels

2021 ◽  
Vol 263 (5) ◽  
pp. 1807-1812
Author(s):  
Chiaki Fenemore ◽  
Yi Yang ◽  
Michael Kingan ◽  
Brian Mace
Keyword(s):  
Building Materials ◽  
Research Council ◽  
Complex Geometry ◽  
National Research Council ◽  
Sound Transmission ◽  
Cross Laminated Timber ◽  
Acoustical Properties ◽  
Lack Of Information ◽  
Stiffness Matrices ◽  
Timber Product

Cross-laminated timber (CLT) is a timber product that is becoming increasingly popular in construction in NZ because of the ability to prefabricate panels off-site, as well as being lightweight and sustainable compared to other building materials. There is currently a lack of information on its acoustical properties, as the complex geometry through the thickness means it is difficult to model and predict sound transmission. The WFE (wave and finite element) method has been employed as it allows for a small segment of a material to be modelled using standard FE methods and can incorporate several material layers. It then requires finding the mass and stiffness matrices of the segment and post-processing them to determine the wave behaviour of the structure as a whole. The WFE method was used to model the sound transmission of several different CLT panels and these results were compared against measurements taken by the National Research Council Canada. In-house testing was also performed to obtain experimental wavenumbers, and these were also compared to wavenumbers produced by the WFE method.

Ice Loads on a Model Podded Propeller Blade in Milling Conditions

2005 ◽  
Author(s):  
Jungyong Wang ◽  
Ayhan Akinturk ◽  
Stephen J. Jones ◽  
Neil Bose
Keyword(s):  
Research Council ◽  
National Research Council ◽  
Propeller Blade ◽  
Hydrodynamic Loads ◽  
Ice Loads ◽  
Advance Ratio

Propeller-ice interaction experiments were conducted in the ice tank at the National Research Council of Canada’s Institute for Ocean Technology. A podded propeller was used in “Puller” mode and loads on an instrumented blade were measured. During the propeller-ice interaction, hydrodynamic loads and ice milling loads were acting on the propeller blade. This paper focuses on the ice milling loads both in water and in air. The ice milling loads, however, cannot be separated from the hydrodynamic loads perfectly. Even if the blade is milling the ice within an ice block, it is still experiencing hydrodynamic loads designated as inseparable hydrodynamic loads. The non-dimensional ice milling loads including inseparable hydrodynamic loads on the blade are presented against advance ratio with varied depths of cut. The results help to reduce the gap of knowledge for interaction between ice and propeller and give information about significant variables acting on the propeller blade during interaction.

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