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

1. Where is Cork port?

Cork port is situated in Cork, Ireland. It is one of the important harbors of the country and has an impressive scale with remarkable throughput.

It has, by its scale, the most extensive quay lengths and terminal facilities areas that could accommodate different types of vessels, while its annual throughput has a considerable quantity of cargo, such as containers and bulk goods, including grains and coal. The port also handles quite a large number of passenger ships.

The port has a wide range of routes. It connects with numerous ports across Europe and other parts of the world, facilitating international trade. It is involved in various business activities that include import and export of goods for different industries such as manufacturing and agriculture.

About the management and operation of the port, there are professional teams managing everything for the smooth running day to day. The authorities have enforced strict safety and security measures to protect port infrastructure and vessels that call at ports.

The port facilities are well equipped. It has modern cranes for loading and unloading cargo, storage areas with appropriate warehousing facilities to keep different types of goods in good condition. There are also facilities for refueling ships and providing other necessary services to vessels.

The channel of the port is dredged regularly for safe passage: ships of different sizes take place. It has the proper navigational aids so that ships entering and leaving the port can have their direct navigation for vessels from various destinations.

2. Why should we measure the ocean currents in the Cork port?

Measurement of ocean currents in Cork port has a lot of significance with regard to its port operation and management. Firstly, accurate current data helps optimize vessel navigation. By understanding the direction and speed of the currents, ships are able to plan their entry and exit routes with much greater efficiency, thereby reducing fuel consumption and time taken for voyages. For instance, if the ships can take advantage of favorable currents, it will save them fuel costs, which is beneficial economically and also helps the environment.

The protection of port infrastructure is another important purpose. Strong or unusual ocean currents could affect the stability of quay walls, berths, and other port facilities. With accurate current measurements, port authorities can take measures in advance to reinforce or maintain such structures as may be necessary.

Additionally, ocean currents are important in marine environmental protection in the port area, where currents contribute to the transportation of pollutants and sediments. With current measurement data, appropriate measures can be taken to manage waste disposal and prevent excessive sediment accumulation that could affect the ecological balance of the port waters.

The ADCP current meter has grown out as a more advanced and handy means of current measurement as compared to the traditional ones. It can provide real-time, detailed information about ocean currents in different depths of the port area with relatively high accuracy.

3. How Do Doppler Principle ADCPs Work?

The working principle behind an ADCP flow meter is based on the Doppler principle. They emit acoustic signals into the water. When these acoustic waves encounter moving particles in the water, such as suspended sediments or small organisms that are carried by the ocean currents, the frequency of the reflected signals will change due to the Doppler effect. By analyzing the difference between the emitted and received frequencies, ADCPs can calculate the velocity of the moving particles and thus determine the speed and direction of the ocean currents.

Among those, in view of the port current measurement in Cork, mainly two common ADCP meter usage methods are given as:

Ship-borne ADCP: In this method, the ADCP current profiler is installed on a ship. As the ship moves around in the port area, the ADCP continuously emits acoustic signals and records the data. By combining the ship's own motion information with the measured current data from the ADCP, a comprehensive picture of the ocean currents in different locations within the port can be obtained. This is useful for surveying a relatively large area of the port waters.

Fixed ADCPs: Fixed ADCPs are installed at fixed locations in the port, such as on the seabed or on fixed structures like piers. They continuously record the ocean currents at a particular location over a prolonged period. This provides a long-term and stable recording of the current conditions in key areas of the port, which is valuable for understanding the regular patterns and any changes in the currents.

4. What is required for high-quality measurement of Cork port currents?

In the measurement of the ocean currents in Cork Port, several factors concerning equipment are important. The materials of the equipment should be highly reliable to withstand the harsh marine environment, including corrosion from seawater, pressure at different depths, and possible impacts from floating objects.

It should be small enough to facilitate easy installation, with minimal interference with any other port operations or structure. The equipment must have a light-weight design so that handling becomes easy, especially in the case of ship-borne ADCPs, which need to be relocated around on ships.

The power consumption should be low, especially for fixed ADCPs, which have to operate continuously for several months. Low power consumption reduces operational and maintenance costs. Low equipment cost also allows for wider deployment for full current measurement across the port.

The casing of ADCP profiler is preferably made from titanium alloy. Titanium alloy has several outstanding advantages. It has very good corrosion resistance in seawater, which means it can keep its structural integrity and performance for a long time in seawater. It also features a high strength-to-weight ratio, which enables durability with a relatively lightweight design. Besides, titanium alloy withstands high pressures at greater depths, which could be applied to different water depth situations in the port area.

5. How to Select the Appropriate Equipment for the Measurement of Current?

Selection of appropriate equipment for current measurement in Cork port depends on the purpose for which these measurements have to be carried out, whether:

Ship-borne ADCP: Where there is a requirement for conducting surveys on a broad area of port waters. Ships can survey different areas of the ports, and ADCPs onboard shall collect the data on currents traversed thereby.

Bottom-mounted ADCP: Especially suitable for long-term measurements at fixed locations within the port-for example, near berths or navigation channels of importance. It guarantees continuous and steady data of the local current conditions.

Buoy-mounted ADCP: This type is very handy when currents are to be measured in areas where installing fixed or using ship-borne ADCPs continuously is inconvenient. The buoys can be deployed in many positions within the port waters.

The depth of the water is another aspect to be considered, and with this, different frequencies are best for different water depths. For instance, an ADCP with a frequency of 600 kHz is adequate for water within 70 meters. In addition, when the water depth increases to up to 110 meters, then an ADCP with a frequency of 300 kHz is preferred. An ADCP with a frequency of 75 kHz provides good current measurements in water as deep as 1000 meters.

Among all ADCPs, the well-known brands include Teledyne RDI, Nortek, and Sontek. In addition, a very recommendable Chinese brand is the China Sonar PandaADCP. This ADCP is made from all-titanium alloy material; thus, ensuring durability, performance, and a pleasant working experience in the water environment. Most importantly, the cost-performance ratio is great. You can learn more about it from its official website: (https://china-sonar.com/).

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