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

1. Where is the Port of Cobh?

The Port of Cobh is situated on the south coast of Ireland, in Cork Harbour. It is a major and historic port with a strategic position.

Port Scale and Throughput

The port has a large scale and significant throughput. It is an important entrance and exit point for trade, receiving cargo in the form of containers, dry bulk, and liquid bulk, such as coal, grains, and petroleum products. The container traffic is a big part of its operations, facilitating the import and export of various manufactured goods. These facilities and infrastructure at the port allow for high-volume shipping, making it a crucial connection in both the Irish and international trade networks.

Route and Business

Cobh port is adequately connected by an efficient network of routes. It connects to the other Irish ports and also with the UK, Europe, and across the globe. Its business operations are diverse. It is a key center for transshipment of goods, with a large container terminal. Besides the shipment, it also has cruise ships handling facilities that bring in a lot of tourists in this area. Besides shipping, it supports other maritime-related businesses, like ship repair and maintenance.

Port Management and Operation

The port management is very efficient and concerned with safety and smooth operations. The berthing of vessels is carefully planned and coordinated in order to minimize waiting times and maximize the utilization of the port's berths. Stringent safety and security measures are implemented to safeguard both the port infrastructure, the vessels, and the cargo. The operations team, responsible for cargo loading and discharge, ship movements within the port, and facility maintenance.

Port Facilities

Modern and extensive facilities are available at the port, which is equipped with deep-water berths that can accommodate the largest ocean-going vessels, including container ships, bulk carriers, and cruise liners. The quay sides are furnished with a range of cargo-handling equipment like cranes of different capacities, conveyor belts, and loading arms for liquid cargo. There are also vast storage areas including warehouses, silos for grains, and large - scale liquid storage tanks. For cruise ships, there are passenger terminals with facilities such as waiting areas, shops, and restaurants.

Channel and Direct Shipping

Cork Harbour provides a natural and well-maintained channel for the port. Regular dredging operations are undertaken to maintain the depth required for shipping. The port has direct shipping links, which make the transportation of goods quicker and more efficient. These links are essential for the role of the port in the supply chain and also to promote trade in the region.

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

Measuring ocean currents in the Port of Cobh is quite necessary on a number of grounds. Firstly, from the point of view of vessel navigation safety, correct current data plays a significant role. The position of the port in Cork Harbour and its relation to the open sea means that vessels are exposed to the impact of several currents. Unpredictable currents can be dangerous to ships while docking, undocking, and navigating the channel. With the correct measurement of currents, the port can give more precise navigational information to ships to avoid accidents and ensure the safety of crew and cargo.

Second, current measurements are vital to any form of effective port operations. Currents can determine how well cargo handling operations will be performed, both in speed and precision. In this regard, while loading or unloading a vessel, for instance, its position will greatly depend on the current. This would give the port more precise timing to schedule these events, therefore maximizing berth usage and enhancing general efficiency in cargo handling.

Lastly, from the perspective of the environment, the understanding of ocean currents is important in managing any potential pollution incidents. Currents can determine the spread of pollutants such as oil spills or other hazardous substances. In this regard, by measuring the currents, the port will be able to take prior measures to minimize the environmental impact and protect the delicate aquatic ecosystem of Cork Harbour and the surrounding coastal areas. ADCP provides a more advanced and convenient means of current measurement compared to traditional methods.

3. How do ADCPs using the Doppler principle work?

ADCPs work on the principle of the Doppler effect. They emit acoustics into the water. It is here that the moving particles of water, suspended sediments, or even small organisms act together. The acoustic signals are reflected back to the Acoustic Doppler Current Profiler(ADCP), with a frequency shift associated with the Doppler effect. This shift in frequency is measured by the ADCP and from it computes the velocity of the water particle, which gives the velocity of the ocean current.

Ship - borne ADCP Ship - borne ADCPs are mounted on vessels. As the ship moves through the port area and the adjacent waters, the ADCP emits acoustic pulses in different directions, typically downward and sideways. The device measures the current velocity at multiple depths as the ship travels. This creates a detailed profile of the current conditions along the ship's path, providing a comprehensive understanding of the current patterns in the areas the ship covers.

Fixed ADCP The fixed ADCPs are installed at specific locations within the port, such as on the seabed or on quay walls. The ADCPs continuously monitor the current at a single point over a longer period. The long-term data collected is very important to understand the characteristics of the current over the long term in key areas of the port, such as at the entrance of the channel or near the berths.

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

For high-quality measurement of ocean currents in the Port of Cobh, the equipment should have reliable materials. Considering that seawater is corrosive and the device may be damaged physically by the marine environment, it should be resistant to these conditions. Small size, lightweight, and low power consumption are also advantageous. A compact and lightweight ADCP is easier to install and operate, whether on a ship or at a fixed location. Low power consumption allows for continuous operation without frequent battery replacement or high energy demands. Cost-effectiveness is also a key factor to enable wide-scale deployment in the port.

The casing of ADCP 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 having a relatively low weight. 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?

As requirements vary, different equipment with respective application specifications should be applied in terms of current measurements in Port Cobh.

Ship-borne ADCP

This is applicable in the case when a broad view of the existing conditions at different parts of the port needs to be studied. As the ship cruises over the port, the ship-borne ADCP would record data from various places to give a wide-ranging vision of the current patterns in port waters.

Bottom-mounted (Sitting on the seabed) ADCP

This kind of ADCP is very ideal for long-term and fixed-point monitoring. This can be installed at the strategic points in the port, such as at the entrance of the channel or near the berths, for continuous monitoring of the current conditions of those particular areas.

Buoy-mounted ADCP

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

Concerning frequency selection, different frequencies correspond to different water depths: for waters up to 70 meters, the corresponding ADCP is 600 kHz; for waters of a depth up to 110 meters, the ADCP frequency is 300 kHz; while for much deeper waters up to 1000 meters, the right choice is a 75 kHz ADCP.

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.