ADCP's Application to Ocean Current Measurement in Leixões Port

1. Where is Leixões Port?

Leixões Port is located on the northwest coast of Portugal, near the city of Matosinhos, in the district of Porto. This prime location on the Atlantic Ocean provides the port with direct access to major trans - Atlantic shipping lanes. It serves as a crucial gateway for Portugal's trade with the Americas, Europe, and other parts of the world. The port benefits from its proximity to the Douro River, which allows for some inland waterway connections and further enriches its transportation network.

Port Scale and Throughput

Leixões Port is a large - scale port with a diverse range of capabilities. It features numerous berths, designed to accommodate various types of vessels. These include large container ships, bulk carriers, and Ro - Ro vessels. The port's annual throughput is substantial, handling a wide variety of cargo. It plays a significant role in the import and export of goods such as automobiles, machinery, and consumer products. Given Portugal's agricultural and wine - making industries, the port also handles a considerable amount of agricultural products and wine for international trade. It is also a hub for project cargo handling, which consists of many large-scale industrial pieces of equipment.

Routes and Business

In totality, the port has a broad network of shipping routes. Among them are direct routes to the key European ports of Rotterdam in the Netherlands, Antwerp in Belgium, and Southampton in the United Kingdom, thus assuring the efficient functioning of cargo within Europe. There are regular shipping lines from Leixões Port to ports in North America, which augment the trans-Atlantic trade. In terms of business activities, Leixões Port is always busy with the handling of general cargo, transshipment of container, and Ro-Ro. It also stores and distributes good through modern storage facilities that easily facilitate the transfer of goods from one place to another. The development of related industries, such as logistics and ship-repair services, has been attracted by the port's location.

Port Management and Operation

The port is managed by the Porto and Leixões Port Authority, with operational activities guided by principles of safety, efficiency, and respect for the environment. Management is in charge of all maintenance tasks concerning the port's infrastructure, including berths, quays, and storage facilities. International shipping regulations are complied with, just as it enforces safety standards and environmental protection. The port authority works in cooperation with shipping companies, freight forwarders, and others to manage operations most effectively and achieve the goal of improving competitiveness at the port. These include initiatives in the improvement of cargo - handling processes, avoidance of long waiting times for vessels, and investment in the latest technologies for port operations.

Port Facilities

The Leixões Port has contemporary and efficient facilities. There are huge capacity container cranes that can load and unload the many containers from large ships quickly and efficiently. For Ro - Ro vessels, it has dedicated ramps and handling areas. The port also has storage areas, including warehouses for general cargo and large - scale open - air yards for bulk commodities. In addition, it has well-equipped ship-repair and maintenance facilities, serving both commercial and local fishing vessels. Specialized terminals have been developed for handling liquid bulk cargo, such as oil and chemicals, ensuring safe and efficient operations. There are also advanced logistics parks adjacent to the port, facilitating the seamless transfer of goods from ship to land transportation.

Waterways and Direct Navigation

The waterways leading to Leixões Port are well - maintained and regularly dredged to ensure safe passage for vessels. The port has a clearly marked channel, and navigational aids such as buoys and lighthouses are in place to assist ships during their approach. It has direct access to the Atlantic Ocean, allowing vessels to easily connect to the global shipping network. The nearby Douro River also provides some opportunities for inland navigation, although it is mainly used for smaller vessels and recreational boating.

2. Why are ocean current measurements needed at Leixões Port?

Navigation Safety

Accurate knowledge of ocean currents in Leixões Port is essential for navigation safety. The Atlantic Ocean's current patterns are influenced by tides, wind, and the circulation of water masses. These currents can have a significant impact on the movement of vessels, especially during berthing, unberthing, and navigation within the port's channels. By measuring the ocean currents, ship captains can make informed decisions, adjust their courses, and avoid potential collisions or groundings.

Port Operations Optimization

While optimizing port operations, ocean current data is quite pertinent. While taking vessels for berthing within the port, consideration must be given to the direction and strength of the current. Strong currents render the berthing operations much more difficult and time-consuming. As a result of accurate measurements of the current, port operators are able to plan optimum times for maneuvers, effectively utilize resources, and improve the overall efficiency of cargo-handling operations. Currents also impact the movements of port-related machinery, like tugboats and floating cranes, and the knowledge of such factors can help in improving safety and productivity during operations.

Environmental Protection

Thus, the measurement of ocean currents is crucial in terms of protection for the environment within the port area. Currents contribute a lot to the solution of the problem of pollutants. In the case of oil leakage or other harmful liquids, prediction of the current pattern will enable the forecast of the spread of contaminants. This allows environmental managers to take preventive measures in time and clean up the sensitive marine ecosystem of the Atlantic Ocean and the surrounding coasts.

The ADCP profiler has become a reliable and efficient tool in measuring ocean currents at Leixões Port, while providing high-precision and real-time data.

3. How do ADCPs using the Doppler principle work?

Measurement Principle

The operation of ADCPs is based on the Doppler effect. When an ADCP meter transmits an acoustic signal into the water column, the sound waves encounter suspended particles in the water, such as sediment or small organisms. As these particles move with the water current, the frequency of the sound waves reflected back to the ADCP is different from the original transmitted frequency. The ADCP measures this frequency shift, known as the Doppler shift. Using the Doppler equation, the instrument can determine the velocity of the water current at each level through the water column.

Specific Means of Measuring Currents in Ports

• Ship-borne ADCP: A ship-borne ADCP is installed on an in-transit vessel. While the ship navigates the waters of Leixões Port, the ADCP flow meter is able to acquire the current velocity at many different depths relative to the ship's course. This type of measurement allows for a broad-scale view of the current conditions within the port and thus is useful for large-scale navigation planning.
• Fixed ADCP: Fixed ADCPs are installed at specific locations in the port, such as on the seabed or on fixed structures like piers or buoys. These ADCPs can continuously monitor the current conditions at a particular point over an extended period, providing valuable data on long - term trends and local variations of the currents.

4. What’s needed for high-quality measurement of Leixões Port currents?

Equipment Reliability

For high-quality current measurement in Leixões Port, the ADCP equipment needs to be highly reliable. With a high level of salinity in the Atlantic Ocean and variable weather conditions, possibly with strong storms, the ADCP should not be subjected to a high frequency of breakdown. Reliable equipment ensures consistent data collection, essential for accurate analysis and decision - making.

Size, Weight, and Power Consumption

The ADCP current profiler should be compact in size and lightweight, therefore easy to install, especially in cases of confined spaces such as on small local vessels or in confined port structures. Another very relevant factor is low power consumption, allowing for the long-term operation of devices, especially fixed-installed ADCPs, which may rely on only battery-powered or solar-powered systems.

Cost-effectiveness

The ADCP should be reasonably priced to enable large-scale measurement in the port area. In this regard, a cost-effective ADCP will allow multiple units to be deployed if necessary to obtain comprehensive current data from different parts of the port.

Material Selection

The housing of the ADCP current meter shall preferably be in the form of a titanium alloy. The utilization of titanium alloy could offer excellent resistance to corrosion that is indeed needed for the long-term utilization in the Atlantic Ocean marine environment. Apart from this, it is also hard but light in weight, meeting the criteria for robustness and easy installation.

5. How to Select the Proper Instrumentation for Current Measurement?

Based on Use

• Ship-borne ADCP: Ideal for large-scale surveys of the port area. When a ship needs to quickly assess the current conditions over a wide range, a ship-borne ADCP is the best choice.
• Sit-on-bottom ADCP: This type is suitable for long - term monitoring of specific locations in the port, such as near the entrance or close to berths.
• Buoy-mounted ADCP: Useful for obtaining data at the water surface and for areas where fixed-bottom installation is not feasible.

Based on Frequency

• For water depths within 70m, an ADCP with a frequency of 600kHz is suitable.
• A 300kHz ADCP is appropriate for water depths up to 110m.
• When dealing with deeper water areas, a 75kHz ADCP is the right choice.

There are several well-known ADCP brands in the market, such as Teledyne RDI, Nortek, and Sontek. However, for those seeking a cost-effective and high-quality option, the Chinese brand China Sonar PandaADCP is highly recommended. It is made of all-titanium alloy material, ensuring excellent durability in the marine environment, and offers an incredible cost-performance ratio. You can see their website at https://china-sonar.com/ for more details.

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