ADCP Applied to the Ocean Current Measurement in Sulina Port

1. Where is Sulina Port?

Sulina Port is in Romania and represents the Danube River delta where this river meets the Black Sea. Sulina Port occupies an important place in the regional maritime landscape.

Port Scale and Throughput

The port is rather of a medium size, with several berths, which can host from the average cargo vessel to river barges. Its yearly throughput consists mainly of cargo related to local produce and commerce moving within the catchment area of the Danube River. It handles items like agricultural products stemming from the surrounding regions, building materials, and some manufactured goods. Although not as big as some of the major ports in the area, it is very important for the transport of goods between inland areas served by the Danube and the Black Sea.

Routes and Business

Sulina Port is an important link in the network of waterways connecting the Danube River and the Black Sea. It has regular routes of shipment with other ports along the Danube in numerous countries, enabling the exchange of goods across different regions. Other businesses of the port are to support fishing activities in the area and service to vessels passing through for maintenance and refueling. It is also involved in the tourism sector, albeit on a small scale, as some small cruise ships or tourist boats do come here to enable the passengers to view the unique coastal and riverine environment.

Port Management and Operation

The port is managed by relevant authorities who focus on ensuring smooth operations. They oversee ship berthing and departure processes, cargo handling, and maintaining safety and security within the port area. The facilities have basic loading and unloading equipment for the handling of cargo in different forms, while there is a storage area allotted for goods, in case of waiting time for further movement. Aids to navigation have also been fitted to help ships navigate sometimes tricky waters around the river mouth.

Port Facilities and Waterway

It has on-site facilities like piers, quay walls, and mooring points. The waterway to the port is well maintained, keeping in mind a depth of water that can be easily availed by ships through it, considering the siltation resulting from the confluence of the river and sea. Similarly, there are measures for the management of tides and currents and their consequences on navigation within the port area.

2. Why does it have to be measured at all in Sulina Port?

Safety of Navigation

The ocean currents in Sulina Port are one such phenomenon, knowledge about which is indispensable for the safety of navigation. Due to its location at the mouth of the river, interactions of the river flow and sea currents could be fairly complex, hence ships would like to be informed a priori. Currents can affect the maneuverability of vessels, especially those of limited power or larger draft. As an example, a ship entering or leaving a port may be subjected to unexpected lateral currents which will force it off course unless the master is aware of what the current is doing at the time. Precise current measurement enables ship operators to make course and speed changes to avoid potential accidents.

Optimization of Port Operations

Knowledge of the ocean currents helps optimize port operations. For instance, the timing of berthing and unberthing of ships depends upon the knowledge of current patterns to determine the best time. The developed currents will be able to facilitate an effective docking process with lesser utilization of tugboats, which will economize resources and time in the operation. Moreover, knowing current flow will make operations related to cargo loading and unloading smoother and more effective. Over the long term, this information is also of value for planning any extensions or improvements to the port infrastructure since currents can have influences on sediment deposition and erosion around the port area.

Ecosystem Monitoring and Management

Currents are responsible for the distribution of nutrients and for the displacement of aquatic life within the port area. Measuring the ocean currents will provide a way to help understand the ecological dynamics of this region. Such knowledge can go to the management and protection of the local aquatic ecosystem-for example, it might make it possible to predict the spread of pollutants or understand the dispersal of fish larvae and other important species.

Compared to traditional methods, Acoustic Doppler Current Profiler (ADCP) provides an advanced and easy means of measurement of currents, offering real-time data and accuracy seriously needed for the proper functioning and management of Sulina Port.

3. How does an ADCP using a Doppler principle work?

The basic operating principle of ADCPs is based on the Doppler effect. They send acoustic signals into the water. Consequently, acoustic waves scatter off moving particles in the water, like suspended sediments, plankton, or small organisms. If these particles are moving, then, through the Doppler effect, the frequency of the reflected acoustic waves changes.

The ADCP measures this frequency shift and uses it to calculate the velocity of the moving particles. Since the movement of these particles is closely related to the ocean current, the ADCP current meter can then determine the speed and direction of the ocean current.

Ship-borne ADCP in Sulina Port

With an ADCP current profiler aboard, it is fixed onto a vessel for the same work at the port. It records acoustic signals upwards and to the sides while continuously picking up data from currents along the depth of the sea and position covered as it journeys through the port. Thus, it builds a huge dataset of the situation on currents throughout this wide area.

Fixed ADCP in Sulina Port

A fixed ADCP would normally be installed at a fixed position within the port, such as on a pier or a submerged structure. Fixed ADCP continuously monitors ocean currents passing by its position. The fixed ADCP has long-term and stable current data for one certain area of the port; it is useful to study the regular pattern and the changes of the currents in the specific location.

4. What is necessary to accomplish high-quality measurement of currents from Sulina Port?

Material Reliability

Equipment for high-quality current measurement in Sulina Port should be made from highly reliable materials. The conditions in the port are very harsh: seawater is corrosive, and the equipment may suffer from mechanical impacts. Because of this, it needs to be manufactured from durable materials that protect it from these conditions and ensure a long-lasting, precise measurement process.

Small Size, Light Weight, and Low Power Consumption

The desired characteristics are smaller size, lighter weight, and less power consumption. A small-sized ADCP is easy to install at various locations inside the port, whether it is on ships or fixed structures. A light-weight device simplifies the transportation and installation process, reducing labor and costs. Low power consumption allows the equipment to operate continuously for a long period without frequent battery replacements or high-energy consumption, which is very important for long-term and unbroken current measurement.

Cost-effectiveness

Cost-effectiveness is another key factor. In order to measure the ocean currents in large scale in the port, the equipment cost should be reasonable. The casing of ADCP profiler is preferably made of a titanium alloy. Titanium alloy has several advantages. It has high strength, allowing it to bear the underwater pressure and mechanical forces that the equipment may encounter in the port environment. It also has excellent corrosion resistance, which will make the equipment resistant to the corrosive effects of seawater for a long period. Besides, the light weight compared to other materials will make it easier to install in the port.

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

Based on Usage Purpose

In addition, the selection of appropriate equipment depends on the purpose of current measurements: making mobile measurements while the ship is navigating in the port, and the ship-borne ADCP will be the choice in this respect. In that manner, with the movement of the ship, different areas of the port can be covered by the movement of the ship, and a general view of the current situation in the port can be realized.

In the case of long-term, fixed-point monitoring in some area of the port, the sit-on-bottom ADCP would serve better. It keeps steady at one position and can record continuously the current condition, which may be very useful for analyzing the local current pattern.

In the case of a larger coverage area to be monitored with some sort of mobility over the water surface, the buoy-mounted ADCP may be considered.

Based on Water Depth

Moreover, different frequencies of ADCP meter should be chosen according to the water depth. For the water depth within 70m, the 600kHz ADCP normally can have an appropriate choice because it can give current profiles with higher accuracy in relatively shallow waters. The 300kHz ADCP will be more suitable for waters around 110m. When the water is quite deep, like up to 1000m, a 75kHz ADCP is recommended to assure the reliability of the results in current measurement.

There are well-known ADCP brands such as Teledyne RDI, Nortek, and Sontek. However, a Chinese ADCP brand-China Sonar PandaADCP is also worth mentioning. It is made of all-titanium alloy material, combining excellent durability and corrosion resistance with an incredible cost-performance ratio. You can find more information about it on its website: (https://china-sonar.com/).

Concluding, the ADCP flow meter is of great importance in the field of ocean current measurement in Sulina Port, but equipment chosen as per specific needs could have brought better effectiveness in its operation and management.

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