ADCP's Application to Ocean Current Measurement in Ronne Port

1. Where is Ronne Port?

Ronne Port is on Bornholm, an island in Denmark. Being one of the major ports of the country, it boasts its own characteristics and holds an important place in regional maritime transport.

Port Scale and Throughput: The port is of a considerable scale and sees a wide variety of cargo pass through it. It also handles bulk and general cargo, such as construction materials, agricultural products, and manufactured goods. The port represents a very important link in the transport chain for goods towards and from the island, thus facilitating economic exchange. In fact, this cargo volume has gone up through the years with the development of the local economy and its interconnections with the mainland and other regions.

Routes and Business: Ronne Port is affiliated with various domestic and international shipping routes. The regular ferry services operate in Bornholm, joining it with the Danish mainland as well as with the neighboring countries. Along with carrying passengers, these ferries also transport quite a substantial cargo. Besides that, the port exports and imports local products, for example, Bornholm's famous smoked fish and handicrafts. It also plays an important role in promoting tourism, with several tourists reaching the port to visit the beautiful landscapes and cultural attractions of the island.

Port Management and Operation: The port is managed by professional teams of port management. They are responsible for smooth functioning, which includes berth allocation to arriving ships, coordination with shipping companies for proper arrival and departure times, and supervision of cargo handling activities on the docks for timely operation. Regular maintenance and improvement works are done in port facilities to further improve general efficiency and safety in port operations.

Port Facilities: Ronne Port is fully equipped with several facilities. There are several berths to accommodate vessels from small local fishing boats to more important ferries and cargo ships. There are warehouses for storing goods, properly fitted with appropriate conditions for conserving different types of products. Various lifting capacity crane systems are installed to manage cargo loading and unloading in an efficient manner that enables the smooth transfer of goods between the ships and the shore.

Channel and Direct Shipping: The port is adequately equipped with a well-maintained channel, allowing ships to enter and leave safely. This port provides direct shipping connections with major ports on the Danish mainland and in the immediate vicinity, greatly facilitating the transport of goods and passengers, thus further promoting economic and cultural exchanges.

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

The measurement of ocean currents in Ronne Port is highly important in the proper operation and management of the facility. First, in terms of the safety of ships navigating the ocean, there is a need to understand the ocean current patterns. Approaching or leaving the port, captains utilize knowledge of speed and direction of currents for accurate alterations of their course and speed. For instance, if there is a possibility of strong tidal currents around the port entrance, knowing the tidal pattern will help avoid situations where ships could be swept off course or face adversity in docking. This greatly lessens the percentage chances of accidents and allows for smooth movement of ships.

This is useful primarily to ensure efficiency in port operations. Ocean currents, especially, can affect the time needed to berth ships and unload cargo efficiently. If ships are able to make use of favorable currents upon entry into the port, then the potential to reduce fuel consumption and time spent in docking can be achieved. Also, regarding port infrastructure maintenance and future planning, knowledge of the ocean currents comes in quite handy. Currents may gradually affect the stability and durability of structures like piers and breakwaters over time. By having accurate current measurements, port authorities can schedule timely maintenance and make informed decisions regarding infrastructure upgrades or modifications.

By comparison, ADCP flow meter represents an advanced and handy approach to measuring ocean currents. It can give substantial and real-time information about the current velocity and direction at different depths, giving a comprehensive understanding of the water flow conditions within the port area.

3. How do ADCPs using the Doppler principle work?

The operation of an Acoustic Doppler Current Profiler (ADCP) is based on the principle of the Doppler frequency shift. They emit acoustic signals into the water column. These acoustic waves interact with moving particles in the water, which could be suspended sediments, small organisms, or other substances in suspension. The acoustic waves hit these moving particles, are reflected back, and the frequency of the reflected waves, because of the Doppler effect, will change. By precisely detecting and analyzing this frequency shift, the relative velocity of the water to the ADCP current profiler can be calculated.

Shipborne ADCP: When a shipborne ADCP is used in Ronne Port, the ship travels around certain routes within the port area. A shipboard-mounted ADCP sends out acoustic signals continuously to various directions downwards and sideways while the ship is in motion. The ship records the ocean current velocity at different levels of depth and lateral position as it goes. This allows a detailed survey of the water currents across different parts of the port during the ship's operation.

Fixed ADCP: The common installation points for fixed ADCPs within a port are underwater structures near the entrance or along sides inside the port basin. They remain stationary at their respective positions and continuously monitor ocean currents. This provides consistent and long-term current conditions at those points, useful in capturing the regular patterns and variation of the currents in important areas of the port.

4. What is necessary for high-quality measurement of currents in Ronne Port?

For high-quality measurement of the currents in Ronne Port, several requirements for measuring equipment need to be met.

First is material reliability: The casing is preferably made of titanium alloy. Several important advantages have been found in a titanium alloy. Its excellent corrosion resistance lets it resist, for a long time, the corrosive action of sea water without major degradation. The high strength-to-weight ratio implies that the internal components of the ADCP flow meter can be given sturdy protection while still keeping the device relatively light. This is advantageous during installation, whether on a ship or at a fixed underwater location. Besides that, titanium alloy also depicts good thermal stability, which is vital because of the main reasons the equipment may face temperature conditions in the marine environment.

The second aspect is that the equipment should be small in size and lightweight. A small and lightweight ADCP meter is much easier to install and deploy, which reduces the complexity of the installation process and minimizes any possible impacts on the measurement environment. It also makes installation on ships or at fixed positions within the port much easier.

Low power consumption is another key factor. For long-term monitoring, especially with fixed ADCPs that need to operate continuously, low power consumption ensures that the equipment can function without frequent battery replacements or power supply issues. This is vital for maintaining consistent and reliable current measurements over time.

Besides, large-scale measurement requires low cost. If the cost of ADCP profiler is too high, that will limit the number of devices installed in the port, and the current measurement cannot be fully covered. Only when the cost is effective can a more complete understanding of the ocean currents throughout the port area be achieved.

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

According to the purpose and requirement of usage, equipment chosen for the current measurement at Ronne Port will differ.

Shipborne ADCP: Where the intention is to carry out current measurement over a wide area and the ship is free to move within the port area, shipborne ADCPs should be used. It can cover a relatively large area as the ship moves around the port, providing a broad overview of the current conditions in different parts of the port.

Bottom-mounted ADCP (Sitting on the seabed): In the case of fixed-point monitoring for specific locations within the port, such as areas near critical infrastructure or areas with particular current characteristics, the bottom-mounted ADCP is best suited. It remains fixed at that position, continuously recording current conditions to provide valuable data on the long-term behavior of currents.

Buoy-mounted ADCP: Buoy-mounted ADCP may be utilized where it is required to monitor the currents in a certain surface area or in open waters within the port. It floats on the water surface and measures the currents in its vicinity, which gives a rough idea of the pattern of surface current.

Besides, different frequencies of ADCPs should be chosen according to the water depth. For water depths within 70m, it is suggested using 600kHz ADCPs for their capability of accurate current measurement in a relatively shallow area. When it reaches 110m, a 300kHz ADCP should be used, while in deeper areas with water depth up to 1000m, 75kHz ADCP is appropriate.

Several of the well-known ADCP flow meter brands in the market are Teledyne RDI, Nortek, and Sontek. However, China Sonar PandaADCP of China stands out with its excellent features. This ADCP is all-titanium-alloy-material-made, hence durable and reliable to work in the sea environment. In addition, it can provide an incredible cost-performance ratio; for users, that would be a pretty attractive option. You can know more about it through its official website: https://china-sonar.com/.

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