ADCP's Application to Ocean Current Measurement in Arrecife Port

1. Where is Arrecife Port?

Arrecife is the capital city of Lanzarote in the Canary Islands of Spain. The Arrecife Port is a key maritime facility in this volcanic archipelago.

Port Scale and Throughput

The port of Arrecife is of medium size. It moves general merchandise, fishing products, and some tourist-related supplies. The volume of throughput is quite high during peak tourist seasons, as it supplies goods to the hospitality industry. It also serves as a base for the local fishing fleet, handling the unloading and distribution of the catch.

Routes and Business

It is connected by shipping routes to other Canary Islands and the Spanish mainland and some international ports. The business dealing mainly concerns the import of consumer goods for both the local population and tourists and the export of local products like handicrafts and agriculture produce from the island. It also involves in the transfer of construction materials to the island, which is being developed and its infrastructure maintained.

Port Management and Operation

The port is managed by a team in charge of efficient management and at the same time environmentally sustainable: it oversees berthing, cargo handling, and also security. Advanced management systems optimize the flow of vessels and goods and enable smooth operations to run with a minimum of delays. It is also concerned with environmental care, considering the fragile sea ecosystem in the Canary Islands.

Port Facilities

Facilities within the port are fitting for its size, having berths for small fishing boats to medium-sized cargo ships. It has equipment such as cranes and forklifts used in loading and unloading cargo of diverse nature. There are storage areas for goods, with cold storage for perishables. Additionally, there are facilities that allow for refueling and basic ship maintenance.

Channel and Direct Shipping

The channel of the port is dredged to a depth that can safely accommodate vessels. The facility has direct shipping links that are essential in supplying goods to the island. These links reduce the time and cost of transport, hence ensuring consistent delivery of supplies.

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

It is very important to measure ocean currents in Arrecife Port. The first reason refers to the safety of navigation: it is necessary to have appropriate, updated data about currents. The Canary Islands are in an area of ocean currents that can take part in entry and exit operations of ships. In fact, if the current data is more accurate, the ship captains can make better decisions to avoid any collision and therefore ensure vessel and port infrastructures' safety.

Besides, when it comes to cargo handling, currents can give way to stability in the operations of loading and unloading. Talking about floating equipment, like cranes or barges, the effect of currents should be considered to develop the efficiency and precision of the transfer of cargo.

Thirdly, knowledge of the ocean currents is important for the prediction of sediment transport and for the maintenance of the depth of channels and berths of the port. Regular current measurements provide valuable data for planning dredging operations and safeguarding the long-term functionality of the port.

It is a more advanced and convenient way to measure currents. It can provide real-time and multi-depth current data, which is very helpful for the operation and management of the port.

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

They work on the Doppler principle, where they emit an acoustic signal into the water. This interacts with particles or any other substances which might be in the current and moving. When the reflected acoustic signals are received, they have a different frequency from what was emitted due to the Doppler effect. Through this frequency shift, the velocity of the water current is calculated.

ADCP in Port Ocean Current Measurement

Shipborne ADCP

The ADCPs installed on the ships, in the form of ships, emit acoustic pulses while moving in the port area-both vertical and horizontal-which measure current velocity at varied depth on the path it moves. These are then relayed to onboard ship control systems in real time for controlling ship courses and speeds regarding the currents.

Fixed ADCP

Fixed ADCPs are deployed on the seabed or on the side of port structures within the port in fixed locations. They continuously cover the current of the sea in a section. The results obtained from fixed ADCP provide long-term information on prevailing current patterns of the port, which aids in port design and maintenance of the structure.

4. What is the requirement for high-quality measurement of currents in the port of Arrecife?

For high-quality current measurement in the Arrecife port, the equipment should be made from materials that are reliable. It has to be resistant to the aggressive marine medium because it will face both corrosion by seawater and changes in pressure. The size should be smaller, lighter in weight, and with lower power consumption. The compact size allows the recorder for more convenient installation in any place at the port. The low power consumption allows longer-term operation without frequent battery replacements or problems with the power supply. Cost-effectiveness is also a key factor to enable the deployment of measurement equipment on a large scale.

The casing of ADCP flow meter should be made of titanium alloy. It has excellent corrosion resistance because long-term usage in seawater requires much stamina. It has a very good strength-to-weight ratio, which will enable it to bear high pressures without burdening the whole equipment with extra weight. In addition, it is biocompatible-it affects the marine environment very little.

5. How to choose the right equipment for the measurement of water current?

Usage Purpose

• Shipborne ADCP: It shall be proper for the measurement of currents during the movement of the ship. It would provide real - time current condition data at the instant when the ship is sailing in the port for navigation and operation safety.
• Sitting-bottom ADCP: It is ideal for long-term, fixed-point monitoring of some area in a port. It gives a continuous view about the current situation in that place, which is useful in understanding the long-term current pattern and also in maintaining the port infrastructure.
• Buoy-mounted ADCP: This is useful when fixed equipment installation is not possible either on the seabed or aboard vessels. These can float in the water and measure the currents around them, thus offering flexibility in the locations of measurements.

Based on Various Frequencies

• Up to 70m water depth, the 600kHz ADCP would be appropriate; it is sufficiently shallow water with accurate current measurements.
• At about 110m, a 300kHz ADCP will do because this will have the ability to measure the current effectively.
• In waters deeper up to 1000m, it is recommended that 75kHz be used for reliable current measurement.
• There are well-known ADCP brands such as Teledyne RDI, Nortek, and Sontek. However, the Chinese brand China Sonar PandaADCP is also a great option. It is made of all-titanium alloy material and offers an excellent cost-performance ratio. You can visit its website (https://china-sonar.com/) for more information.

Here is a table with some well known Acoustic Doppler Current Profiler(ADCP) instrument brands and models.