Real-time and historical data gathering provided by specific Eniram technologies has proven again that this kind of visibility on board one vessel or across entire fleets is crucial information ship owners and operators need to know in order to fully optimize fuel and propulsion efficiency.
One of Eniram’s latest propulsion analysis studies involved global container operator Hamburg Süd. In early 2013, the company which operates a fleet of more than 105 vessels with a capacity of over 454,000 TEUs, replaced the pre-swirl stators originally installed on its Santa class vessels with the new Becker Marine Systems’ Twisted Fin (BTF), a further development of the Becker Mewis Duct®.
Eniram’s Dynamic Trimming Assistant (DTA) including the Eniram Vessel Platform (EVP) system for collecting real time data from the vessel had been installed aboard the container vessel Santa Catarina in 2011 to optimize vessel trim. In order to analyze the validity of the ship’s new propulsion system the high frequency data collected from the vessel was used. Eniram’s suite of optimal operational data-gathering and monitoring systems include those for trim, speed, engine load, and hull fouling.
The EVP system interfaces with a vessel’s data from the bridge and associated automated systems and measures real-time vessel performance and fuel consumption. In this case, it was important to see the results of improved efficiency of the propeller by optimizing distribution of water to the propeller.
Eniram’s systems gather data on a high-frequency highly-accurate basis; they take two measurements every minute as opposed to the traditional manual noon report recording of one measurement a day. The data is then stored in Eniram’s secure Data Bank for further analysis and future modelling. As part of my job as head analyst, I ensure we use the data to provide customers insight and information for strategic decision-making and efficient operations.
Model tank tests of the BTF had indicated a favourable effect on the fleet, and in the case of Hamburg Süd’s Santa Catarina, since we already had existing data collected from the ship for two years previous, in the flash of a few minutes, we were easily able to select operational data from three months previous to the twisted fin installation as well as three months afterward to carry out our propulsion efficiency analysis. Additionally, in order to analyze the vessel’s performance in similar conditions, periods in laden (draft more than 11 meters) and ballast (draft below 10 meters) were chosen for comparison.
The key system that produced results was Eniram’s Propulsion Power Decomposition (PPD) technology. No other major operations were done at the installation of the twisted fin, which meant that the change in performance was undoubtedly attributed to the twisted fin. The PPD model allows us to eliminate the impact of variable environmental conditions such as wind, sea state, trim and squat (called the dynamic sea margin) and create a hydrodynamic model of the vessel to simulate the impact to ensure a more accurate performance comparison in the before and after installation scenario.
We measured Santa Catarina in both laden and ballast conditions, divided the speed-power curves before and after the BTF installation and compared those to different speed areas. In laden conditions, there was no visible change under 15 knots. From 15 to 18 knots, there was a 1-3 % impact and above 18 knots, there was a 4-7% impact. The vessel’s average median operational speed being 19.4 knots.
With similar criteria, we measured the ballast data, which saw an improvement in propulsion efficiency of 2%. We then calculated how much time the vessel spent at sea at each speed and compared it to the energy consumption during that time and multiplied that propulsion energy by the impact of the BTF which resulted in a total of 3.5% propulsion energy savings.
Thanks to Eniram’s combined DTA and PPD technology and real-time sea condition data-collecting, we were able to confirm the original theoretical calculations worked. Our systems not only help continuously automate and streamline how ship efficiencies are measured but our systems also remove the possibility of human error when collecting data, saving operators time and money while providing complete clarity of a ship’s performance at sea.
ABOUT THE AUTHOR
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Pekka Autere is part of Eniram’s analytics team and has a broad experience in converting data into information and strategic guidance using mathematical and statistical modeling in different fields of application. He is responsible for developing automatic reporting and data analysis with our customers. He is a Master of Science in Automation and System Technology and System Analysis and a Master of Social Sciences in Economics. |
ABOUT ENIRAM
Established in 2005, Eniram provides the maritime industry with energy management technology to reduce fuel consumption and emissions. Created by experienced seafarers and technologists, Eniram’s solutions range from single onboard applications to comprehensive fleet analysis. Eniram is headquartered in Helsinki, Finland and has subsidiaries in the UK, the USA, Germany and Singapore. www.eniram.fi
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