ADCP's Application to Ocean Current Measurement in Setúbal Port

1. Where is Setúbal Port?

Setúbal Port is located in the city of Setúbal in Portugal. It is the most important port in this region and plays a very critical role in both local and international maritime trade.

Port Scale and Throughput

The port is of considerable size and caters to most types of cargo. Throughput includes agricultural products from the hinterland, fishery products because of proximity to fishing grounds, and industrial products. Its infrastructural arrangement is for a high level of trade and has the capacity for different sizes of vessels, from small fishing boats up to medium-sized cargo ships.

Routes and Business

Setúbal Port has good connectivity both domestically and internationally. On the national level, this port works as a nodal connecting point in the transportation system of the country. Its international business relations include trading with almost all European ports and a number of North African ports. The major types of businesses that are executed here are loading and unloading of cargo, storage in the warehouses, and services for handling and distribution of cargo. The port also includes a fishing port area, important to the local fishing industry, providing facilities for fishing vessel docking and fish processing.

Management and Operation of the Port

The port is managed by local port authorities responsible for the smooth operation of the port. They oversee everything related to vessel traffic management, keeping the port area safe and secure, and maintenance of the port facilities. It continuously goes on maintaining and upgrading the berths, warehouses, and other infrastructure necessary to keep the port working smoothly. The port authorities also coordinate with customs, immigration, and other regulatory agencies to ensure that all relevant laws and regulations are complied with.

Facilities

Setúbal Port has berths, which can accommodate different types of vessels. There are warehouses for the storage of all kinds of goods, even those requiring special temperature control. Loading and unloading equipment, like cranes and forklifts, may also be provided to transfer cargo. Besides that, the port provides the ships with necessary services like refueling, water supply, and waste disposal. In the fishing port area, there are fish-processing plants and cold-storage facilities for fishery products.

Channel and Direct Shipping

The port has a well-maintained channel, allowing for safe entrance and exit. The depth and width of the channel are reasonable to handle the vessels passing through it. It enjoys direct shipping connections with other important ports, therefore ensuring smooth processing of transportation, hence increased trade.

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

Safety of Navigation of Ships

In return, it is very important to provide appropriate and timely measurements of currents within the Setúbal Port for the safety of the ships. Knowledge about current direction and speed plays an important role for masters and pilots during berthing and departure. In this sense, current data from within a port can, when taken into consideration, avoid collisions with port structures or other vessels. Particularly so when weather conditions are unfavorable, with larger ships having more difficulties in maneuverability.

Optimization of Port Operations

This ocean current information is important in optimizing the operations of the port. Different current conditions would affect the time and efficiency of loading and unloading cargo. For example, strong currents may require adjusting the positioning of the ship or deploying additional mooring equipment to ensure the safety of the workers and the integrity of the cargo. Accurate current measurements enable port operators to schedule and handle such operations more effectively; this reduces delays and contributes to higher productivity in general.

Long-Term Port Development

It is important to understand the ocean currents for the long-term development and expansion of the port. Hydrodynamic forces due to the currents will affect the stability and durability of structures in the port, such as berths and piers. This information is necessary for engineers in the design and construction of new infrastructure with the ability to resist such forces. It helps to decide on the most feasible place for further expansion and improvement with minimal negative effects from the flow of water.

Acoustic Doppler Current Profiler (ADCP) represents a modern and more convenient way of measuring ocean currents compared to traditional methods. It can give detailed current information at different depths quickly and precisely, offering real-time data indispensable for the efficient operation and further development of Setúbal Port.

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

ADPCs work on the principle of Doppler. They send acoustic signals into the water. The acoustic waves scatter off suspended particles or other objects in the water moving with the ocean current. When those waves reflect back to the ADCP meter, the frequency of the reflected waves is different from the transmitted one through a frequency shift due to the Doppler effect.

From this Doppler shift analysis, the ADCP current meter will be able to find out the velocity of the ocean current at various depths.

ADCP in Port Ocean Current Measurement

Shipborne ADCP

Shipborne ADCPs are installed on ships operating in and around Setúbal Port. While the ship navigates around the area of the port, the ADCP current profiler continuously emits acoustic signals in various directions. It can measure the ocean current at multiple points along the path of travel of the ship, therefore offering a comprehensive view of the current distribution in the area covered by the movement of the ship.

Fixed ADCP

Fixed ADCPs can be deployed at a specific location, such as on the ocean floor near structures that are considered important or at specific locations in the waterways of traffic. They would monitor, over an extended period of time, conditions that the ocean currents go through at any particular location. This provides very valuable data of the regular patterns this current usually follows and its interference with the port facilities at that fixed point.

4. What is required to have the quality measurement of Setúbal port currents?

Material Reliability

The equipment should be made of reliable materials to provide high-quality measurement in the ocean currents of the Setúbal Port. The materials should resist the aggressive marine conditions of saltwater corrosion, changes in water pressure due to changes in depth, and the constant oscillations due to waves without jeopardizing the performance of the measuring device. Titanium alloy is highly recommended in ADCPs for its casing. It provides high strength, and it resists the mechanical forces of the marine environment; it also has excellent corrosion resistance that makes it durable in seawater.

Size, Weight, and Power Consumption

It should also be compact in size, light in weight, and low in power consumption. The smaller the size, the easier it would be to install in many areas around the port, whether on ships or at fixed locations. Light in weight will facilitate handling and deployment, and low power consumption ensures that the equipment can run continuously without the need for frequent battery replacement or excessive power supply.

Cost-Effectiveness

Cost-effectiveness is essential for extensive measurement. The equipment needs to have a reasonable price to be able to spread in the port for wide-range use with the purpose of acquiring whole current data.

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

Based on the Purpose of Usage

• Shipborne ADCP: The objective may be to make mobile measurements while the ship is navigating in the port area in order to have a broad overview in as short time as possible of the situation in various parts of the port. During this movement, a wide area can be covered.
• Bottom-mounted ADCP: When there is interest in the continuous and long-term monitoring of the ocean current at a specific, fixed location in the port, such as near very important facilities or areas that need close observation of currents' impacts on structures. Bottom-mounted ADCP carries out stable and consistent data measurement at a fixed position.
• Buoy-mounted ADCP: In cases where it is not convenient to install fixed equipment on the seabed or on other structures, buoy-mounted ADCP can be used. The buoy-mounted ADCP can measure the ocean current in the upper layers of the water body and transmit the data wirelessly.

According to Different Frequencies

• For water depth within 70m in the Setúbal Port, 600kHz ADCP is usually a suitable choice as it can provide accurate current data in this depth range.
• For water depths of about 110m, 300kHz ADCP should be more appropriate since at this depth, it could better capture the characteristics of the current.
• For deeper water areas with a water depth up to 1000m, 75kHz ADCP should be selected because it can go deeper and get reliable current information.

There are well-known ADCP brands such as Teledyne RDI, Nortek, and Sontek. However, a Chinese ADCP brand, China Sonar PandaADCP, is also worth considering. It is made of all-titanium alloy materials and offers an excellent cost-performance ratio. You can learn more about it at (https://china-sonar.com/).

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