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

1. Where is Coleraine port?

Coleraine port is situated in Northern Ireland. It is a smaller yet significant port in the area.

Port Scale and Throughput

While some of the bigger ports show more impressive throughput volumes, Coleraine port still receives a quantity of cargo. It fulfills its function of maintaining local trade and specific goods. Serving as a junction point for freight transport inland and around Coleraine, this enables the supply of farming produce, construction materials, and other vital merchandise.

Routes and Business

Its shipping routes connect the port to various regional ports. The shipping operations carried out are coastal and short - sea in nature. Commercially, the activities undertaken by the port include the export of local produce and import of goods related to the local industries and construction sectors.

Port Management and Operation

The port management ensures the effective use of its resources. Berthing arrangements are made to ensure smooth docking of vessels. The operation also emphasizes the safety and security of the port, with measures in place to protect the cargo and the infrastructure. The port staff coordinates the loading and unloading of goods to maintain a steady flow of operations.

Port Facilities

Coleraine port has basic but well-maintained facilities. It has a few berths that can accommodate vessels of different sizes suitable for its scale of operations. There are storage areas for holding cargo before and after transportation. The port also has equipment like cranes and forklifts to handle the loading and unloading of goods.

Channel and Direct Shipping

The channel of the port is dredged to maintain safe passage for ships. It might not have a very extensive direct shipping network as larger ports would, but it connects to key regional destinations nonetheless. This is essential for local economies and facilitates trade in goods that support local industries and businesses.

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

The measurement of ocean currents in the Coleraine port is important for a number of reasons. It would contribute to safe navigation by vessels. The relatively small size of the port and its channel layout make it necessary that accurate knowledge of current patterns be ascertained for ships to enter and leave the port without incident. Even small-to-medium-sized vessels can be affected by unexpected currents, and having up-to-date current information helps in providing precise navigational guidance.

Secondly, for efficient port operations, current measurements are valuable. Currents can influence the time and precision required for cargo handling. For example, if the current is strong, it can make the docking process more challenging and affect the stability of the vessel during loading and unloading. By having accurate current data, the port can better schedule these operations and optimize the use of its berths.

Finally, from an environmental point of view, knowledge of the currents aids in the monitoring and management of any potential cases of pollution. Currents will determine the spread of pollutants, and by measuring them, the port can take proactive measures to minimize the environmental impact. This is more advanced and efficient compared to traditional methods of measuring these currents.

3. How do ADCPs using the Doppler principle work?

The principle behind the operation of ADCPs is the Doppler principle. They emit acoustic signals into the water. These interact with the moving particles in the water, such as suspended sediments or small organisms. When the acoustic signals are reflected back to the ADCP current meter, a change in frequency due to the Doppler effect takes place. This frequency shift is measured by the ADCP, which then calculates the velocity of the water particles, hence giving the velocity of the ocean current.

Ship-borne ADCP

Ship-borne ADCPs are installed on vessels. While the ship is in motion around the area of the port, there is a release of the acoustic pulses from the ADCP flow meter in various directions, commonly downwards and sideways. During its journey, the device takes the current velocity at the various depths of travel, thereby giving a very detailed profile of the current conditions along the path which the ship covers, making for an accurate understanding of the current patterns in the area the ship covers.

Fixed ADCP

Fixed ADCPs are placed in fixed locations within the port, either on the seabed or on quay walls. These ADCPs continuously record current at a single point over time. The data collected over time is crucial for understanding the long-term current characteristics in key areas of the port, such as the entrance of the channel or near the berths.

4. What's required for high-quality measurement of Coleraine port currents?

For high-quality measurement in the ocean currents of Coleraine port, equipment with reliable materials is necessary. As seawater is corrosive and there is physical damage from the marine environment, this device must be designed with durability in mind. Its size should be small; it should be lightweight, with low power consumption. In short, an ADCP current profiler is more compact, lightweight, and therefore far easier to install and operate at any place, whether on board a ship or fixed location. Low power consumption enables this model of sonar instrument for continuous operation without frequent changes of batteries or high consumption of energy. Cost-effectiveness is another important factor for wide-scale deployment in a port.

The casing of ADCP profiler is preferably made of titanium alloy. Titanium alloy has excellent corrosion resistance in seawater, ensuring the long-term integrity of the device. Besides, it has a high strength-to-weight ratio, which means it can be strong and durable while keeping the weight relatively low. In addition, titanium alloy is biocompatible, which reduces the potential negative impact on the marine environment.

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

The choice of the right equipment for current measurement in Coleraine port 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. While the ship moves around the port, it is possible to collect shipborne ADCP data from various locations, providing a wide-ranging view of the current patterns in the port waters.

Bottom-mounted (Sitting on the seabed) ADCP

This type of ADCP meter is ideal for long-term and fixed-point monitoring. It can be installed at strategic points in the port, like at the entrance of the channel or near the berths, to continuously monitor the current condition in those specific areas.

Buoy-mounted ADCP

Buoy-mounted ADCPs are useful for applications where the installation of a fixed device on the seabed or on a ship is not practical. They can be deployed in open water areas inside the port to measure the current at different depths.

Not all ADCPs are created equally; each differs regarding a number of characteristics, mainly frequency selection. A 600 kHz ADCP should suffice in water as deep as 70 meters, a 300 kHz ADCP in as deep as 110 meters of water, and a 75 kHz ADCP in waters as deep as 1000 meters of water.

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.