ADCP Application for the Measurement of Ocean Currents in Aveiro Port

1. Where is Aveiro Port?

Aveiro Port is in the Aveiro city of Portugal. It is an important regional facility, famous for its canals and a lagoon system.

Port Scale and Throughput

The size of the port is quite considerable, and it contributes greatly to the local and regional economy. It handles a wide variety of cargo, from the traditional product of the area, salt, to agricultural products, building materials, and a variety of industrial goods. The throughput has been steadily growing as the port's infrastructure and connections have improved. It can accommodate a variety of vessels, from small fishing boats and barges to medium-sized cargo ships.

Routes and Business

Besides the important trade links, Aveiro Port has good connections with other domestic ports. It plays a vital role in the national transportation network for the distribution of goods within Portugal. It is also internationally connected, especially with other European ports. The main business activities include cargo loading and unloading, storage in warehouses located near the port and along the canals, and value-added services related to packaging and sorting. The port also serves as a base for fishing activities, with facilities for fishing vessels to berth and unload their catch.

Port Management and Operation

The port is managed by both local authorities and those specific to the port management itself. They ensure that the port functions properly, which includes managing vessel traffic, keeping the port area and the canals safe and secure, and overseeing the maintenance of port facilities. The canals, docks, and warehouses are regularly under maintenance for smooth functioning. Management also coordinates with customs and other regulatory agencies in the handling of the flow of goods.

Port Facilities

Aveiro Port is equipped with docks and quays that can handle different types of vessels. There are extensive warehouse facilities, some of which are located along the canals and are accessible by boat. The port has loading and unloading equipment such as cranes and forklifts to facilitate the transfer of cargo. It also provides services such as refueling for vessels, freshwater supply, and waste disposal. Besides, there are fish -processing plants and cold -storage facilities for the fishing industry.

Channel and Direct Shipping

It has also developed a fine canal system, allowing the innermost parts of the port to be accessed by vessels. Dredging is often carried out to maintain the correct depth in canals for vessels to pass through. It may not be like the number of direct international shipping lines passing through larger ports, but it enjoys connectivity with some important domestic ports and some international destinations, helping to move goods smoothly.

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

Navigation Safety

Measurements of the ocean currents are of utmost importance at Aveiro Port in view of the safety of ships. Knowledge of the direction and speed of the current is helpful for the masters and pilots of vessels during berthing and departure, particularly in the complex canal system. Precise current data helps prevent collisions with port structures, other vessels, or the banks of the canals, a condition that is especially critical during periods of high traffic or adverse weather conditions.

Optimization of Port Operations

The information on ocean currents is of great importance for the optimization of port operations. Other current conditions may affect time and efficiency in cargo loading and unloading. For example, strong currents may require adjusting the positioning of the ship or employing additional mooring equipment to ensure that workers are safe and the integrity of the cargo is guaranteed. With proper current measurements, port operators can plan and coordinate these activities better to minimize delays and increase efficiency.

Port Infrastructure Planning

In the long run, the planning and development of the port would require an understanding of the ocean currents. The hydrodynamic forces exerted by the currents can impact the stability and durability of port structures such as docks, quays, and canal walls. This information is crucial for engineers in designing and constructing new infrastructure that can sustain such forces. It also aids in pinpointing the best locations to make further improvements that can minimize the detriments of the flow of water.

Measuring the current compared with traditional methods, an Acoustic Doppler Current Profiler(ADCP) has a much advanced and convenient way. Compared with other methods, this can give rapid detailed information on current at different levels and in real time-an indispensable base for effective performance and further development of Aveiro Port.

3. How does the Doppler principle work in ADCPs?

The working principle of ADCPs is based on the Doppler effect. ADCPs transmit acoustic signals into the water. These acoustic waves are scattered by the suspended particles or other objects in water that are moving along with the ocean current. When the waves are reflected back to the ADCP, the frequency of the reflected waves shifts due to the Doppler effect.

With the frequency shift analysis, the ADCP estimates the velocity of an ocean current at a different depth.

ADCP in Port Ocean Current Measurement: Shipborne ADCP

Shipborne ADCPs are installed on ships operating in and around Aveiro Port. While the ship is sailing over the area of the port, the ADCP continuously emits acoustic signals in various directions. It can measure the ocean current at several points along the path followed by the ship, hence giving an overview of the current distribution in the area covered by the movement of the ship.

Fixed ADCP

Fixed ADCPs are generally fixed at a location in the port, say at a seabed near critical installations or at a strategic point along the waterway, but continuously monitor the conditions at that point over a longer duration. This gives extremely valued data about the cyclic condition of the current and the manner in which it affects the installations around that fixed point of the port facilities.

4. What does high - quality measurement of Aveiro port currents need?

Material Reliability

High-quality measurement of the ocean currents around Aveiro Port requires equipment fabricated with reliable materials. Given the unforgiving marine environment due to conditions such as saltwater corrosion, water pressures that vary with depth, and the unrelenting action of waves, the materials should be such that they can bear such rigors without compromising on the performance of the measurement device. The casing for ADCPs can be of titanium alloy. It has high strength, which can resist mechanical forces in the oceanic environment, and it also has excellent corrosion resistance, which can ensure its service life in seawater.

Size, Weight, and Power Consumption

It should also be compact, lightweight, and low power-consuming. The size can be small to enable easy installation in various parts of the port, whether on ships or fixed locations. Lightweight enables easy handling and deployment while low power consumption ensures that the equipment operates for a long period without the need to change batteries frequently or use too much power.

Cost-Effectiveness

The cost-effectiveness is a critical point of the large-scale measurement; the price of the equipment should be reasonably affordable to enable the usage of more sets in the port for acquiring overall current data.

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

According to the Usage Purpose

• Shipborne ADCP: When the purpose is to do mobile measurements while the vessel is navigating in the port area for a quick understanding of the current situation in various areas of the port, then Shipborne ADCP will be highly suitable. It covers huge areas during the movement of the ship.
• Bottom-mounted ADCP: In applications when continuous, long-term monitoring of ocean current at some fixed positions in the port, e.g., around important facilities or areas that might have to be kept under close observation with regard to the impact of current on structural or other works, the bottom-mounted ADCP will be more appropriate. It gives series data in a fixed position very steadily and consistently.
• Buoy-mounted ADCP: In situations when the fixation of fixed equipment on the seabed or on any other structure is not possible, buoy-mounted ADCPs can be utilized. The buoy-mounted ADCP can measure the ocean current at the upper layers of a water body and transmit wirelessly.

Based on Various Frequencies

• As for water depth within Aveiro Port at 70 m or less, 600kHz ADCP is usually not at a disadvantage in providing an accurate current data.
• However, in the case of having water depth around 110 meters, the 300 kHz ADCP is more advantageous to be able to see the current characteristics at the depths.
• In deeper water areas, the 75kHz ADCP should be chosen because it has deeper penetration and can obtain reliable current information up to 1000m.

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.