ADCP's Application to Ocean Current Measurement in the Port of Shannon Foynes

1. Where is the Port of Shannon Foynes?

The Port of Shannon Foynes is located in County Limerick, Ireland, on the Shannon Estuary. It is a major and strategic port in the region.

Port Scale and Throughput

The port has a large scale and substantial throughput. It is a key player in the handling of all types of cargo, including liquid bulk (such as petroleum products), dry bulk (like coal, ores, and grains), and containers. The port's facilities and infrastructure allow it to handle significant volumes of imports and exports, playing a crucial role in the Irish and international trade network. The throughput figures have been on the increase over the years, reflecting its importance in the economic landscape.

Routes and Business

It has an excellent connectivity due to a vast network of routes on the sea. It shares this connectivity with other Irish harbors, as well as with those in the UK, Europe, and beyond. As far as the businesses that are associated with it, it is a versatile hub. It is considered as one of the crucial places for the storage of liquid fuels and their distribution pipeline with storage tanks. It has various dry bulk handling operations, which support the construction and energy production industries. It also deals in container traffic, thereby helping in the transportation of a wide range of manufactured goods.

Port Management and Operation

The management is very efficient and focuses on the safety and smooth operations of the port. The berthing of vessels is carefully planned and coordinated so that the waiting time for all vessels is minimized and full use is made of the berths. Safety and security are strictly observed in the protection of the port infrastructure, the vessels, and cargo. The operations team is in charge of cargo loading and unloading, the movements of ships within the facility, and the general upkeep of the facilities.

Port Facilities

The port is endowed with modern and extensive facilities. Deep-water berths can receive ocean-going vessels of large capacity, such as tankers, bulk carriers, and container ships. Quay sides are equipped with a variety of cargo-handling gear that includes cranes of different capacities, conveyor belts, and loading arms for liquid cargo. There are huge storage areas comprising warehouses, silos for grains, and large-scale liquid storage tanks.

Channel and Direct Shipping

The Shannon Estuary provides a natural and well-maintained channel for the port. Regular dredging operations are carried out to maintain the required depth for shipping. The port has direct shipping links that enable quick and efficient transportation of goods. These connections are important for the port's role in the supply chain and also for promoting trade in the region.

2. Why should we measure ocean currents in the Port of Shannon Foynes?

Measurement of ocean currents is necessary to be conducted at the Port of Shannon Foynes due to several reasons. To start with, vessel traffic requires current data to maintain safety of navigation. Its location on the estuary and its exposure to open sea link the vessels passing through it with variable current conditions. Unpredictable currents can be dangerous for ships while docking, undocking, and navigating the channel. Measuring the currents correctly will enable the port to give more accurate navigational information to ships, thus reducing the chances of accidents and the loss of life and cargo.

Current measurements are also of paramount importance for the efficient performance of port operations. Currents can affect the speed and accuracy of cargo handling operations. For instance, the current can significantly affect the position of a vessel while loading or unloading. The port will be in a better position to schedule these operations, optimize the use of berths, and increase the overall efficiency of cargo handling with accurate current data.

Finally, from an environmental point of view, the understanding of currents is very important in cases of potential pollution. Currents can determine the spread of pollutants such as oil spills or other hazardous substances. By measuring the currents, the port can take in-advance measures to reduce the environmental impact and protect the sensitive aquatic ecosystem of the Shannon Estuary and the surrounding coastal areas of the above body of water. Acoustic Doppler Current Profiler (ADCP) provides a more modern and convenient way of measuring current compared to traditional methods.

3. How do ADCPs using the principle of Doppler work?

The ADCPs work on the principle of the Doppler effect. They send acoustic signals into the water. These signals interact with moving particles in the water, such as suspended sediments or small organisms. When the acoustic signals are reflected back to the ADCP profiler, a frequency shift occurs due to the Doppler effect. The ADCP measures this frequency shift and calculates the velocity of the water particles, which in turn gives the velocity of the ocean current.

Ship-borne ADCP

Ship-borne ADCPs are mounted on vessels. During its movement through the port area and adjacent waters, the ADCP emits acoustic pulses in different directions, typically downward and sideways. As the ship moves, it measures the velocity of current at different levels of depth. This thus forms a very thorough profile of current conditions along the ship's track, thereby forming a good understanding of current patterns across the areas the vessel would cover.

Fixed ADCP

The fixed ADCPs are installed in some fixed locations in the port, either at the seabed or on quay walls. These ADCPs measure current continuously at a single point over a longer period. The data acquired for a long time will be valuable for understanding the characteristics of the long - term current in the most important areas of the port, such as the channel entrance or near the berths.

4. What's needed for high-quality measurement of Shannon Foynes port currents?

The equipment to be used for high-quality measurement of ocean currents in the Port of Shannon Foynes should be made of reliable materials. Since seawater is corrosive and the device may be exposed to physical damage caused by the marine environment, it should be able to withstand such conditions. Small size, light weight, and low power consumption are also advantageous. A compact and lightweight ADCP current meter is much easier to install and operate, whether on a ship or at a fixed location. Low power consumption will enable continuous operation without the need for frequent battery replacement or high energy demands. Cost-effectiveness is also a key factor in wide-scale deployment in the port.

The ADCP current profiler casing shall be fabricated from a Titanium alloy. This will definitely give good corrosion resistance in seawater and maintain its integrity over the long run. Also, the alloy is much stronger for its weight and will provide an acceptable trade-off between robustness and low weight. Another good point is the biocompatibility of this alloy, which minimizes adverse environmental impacts on the sea environment.

5. How to Choose the right equipment for current measurement?

The choice of the right equipment for current measurement in the Port of Shannon Foynes depends on the specific requirements.

Ship-borne ADCP

This is suitable when a broad overview of the current conditions in different parts of the port is needed. As the ship sails around the port, the ship-borne ADCP can collect data from various locations, providing a wide-range view of the current patterns in the port waters.

Bottom-mounted (Sitting on the seabed) ADCP

The type of ADCP meter, therefore, allows it to be suitable in a normal long-term monitoring at fixed points. To monitor, for instance, the constant current condition that has a strategic position to install them at certain critical points like the entrance into the channel or even berth areas around the entire port.

Buoy-mounted ADCPs are applicable where a fixed device installation either on the seabed or on a ship is not practical. They can be deployed in open water areas within the port to measure currents at different depths.

Regarding frequency selection, different frequencies are suitable for different water depths. A 600 kHz ADCP is appropriate for water depths up to 70 meters, a 300 kHz ADCP for depths up to 110 meters, and a 75 kHz ADCP for much deeper waters up to 1000 meters.

There are well-known ADCP brands like Teledyne RDI, Nortek, and Sontek. However, there is also a Chinese ADCP brand, China Sonar PandaADCP. It is made of all-titanium alloy material, which ensures its durability in the marine environment and offers an excellent cost-performance ratio. You can find more information on its website: (https://china-sonar.com/).

Here is a table with some well known ADCP instrument brands and models.