Application of ADCP to Ocean Current Measurement in Busan Port

1. Where is Busan Port?

Busan Port is located in Busan, South Korea. On the southeastern coast of the Korean Peninsula at the entrance of the Korea Strait, it stands out due to its strategic position. That positions it as one of the very critical gates in Northeast Asia's ocean transportation market.

Port Scale and Throughput

Busan Port is one of the largest and busiest in the world, having a great length of quays and huge terminal areas. The annual throughput recorded at the facility is impressive and has grown over the years, with a lot of container cargoes, bulk cargo, and liquid cargo being handled. It also serves as a major global container handling hub, with a capacity to handle a significant number of twenty-foot equivalent units. It acts as a transshipment center, also connecting shipping routes across different parts of the globe: Asia, Europe, and the Americas.

Routes and Business

It has an extensive network of shipping routes, which have been a significant part of the supply chain the global village depends on for the movement of goods such as electronics, automobiles, and consumer goods. Busan Port business is multifaceted. It participates in container shipping operations with several international shipping lines offering regular services. Besides that, it also handles large volumes of bulk commodities such as coal, iron ore, and grains. In addition, it has a developing cruise ship business that attracts tourists and injects money into the local tourism economy.

Port Management and Operations

The port is operated by the Busan Port Authority. This body is responsible for the overall planning and development of the port, as well as the smooth running of activities within the port. It is also involved in maintenance work at the port, vessel traffic control, safety, and security. The port authority also pursues the development of the port's competitiveness through port expansion, technological innovation, and cooperation with other ports and logistics providers.

Facilities of the Port

Busan Port is a facility that boasts state-of-the-art facilities. Advanced gantry cranes and automated container-handling systems within the container terminals can load and unload containers with high efficiency. Large storage areas are given for containers and other cargo. As for liquid and bulk cargo, there exist specialized terminals fitted with pipelines, conveyor belts, and storage tanks. The port also has repair and maintenance facilities for ships, including dry docks and workshops. In addition, there are facilities for crew services, such as accommodation and catering.

Channels and Direct Navigation

The approach channels to Busan Port are well-maintained and deep enough to accommodate large-draft vessels. The depth is regularly monitored and dredged as needed. Navigation can be assisted by buoys, lighthouses, and radar systems. Vessels are able to enter the port directly from the open sea due to the presence of marked shipping lanes. The heavy volume of traffic necessitates strict regimes in terms of traffic management and scheduling in order to facilitate navigation in a smooth and safe manner.

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

Ocean current measurement in Busan Port is important for several reasons.

Navigation Safety

With the high volume of ships passing through Busan Port, knowledge of ocean currents is vital for safe navigation. Currents can affect a ship's speed, course, and maneuverability. For example, a strong cross-current may push the ship off-course while berthing or in narrow channels and increase the danger of collision with other vessels or port structures. Precise measurement of the currents enables the captain to make better-informed decisions and adjust his navigation plans in order to prevent accidents.

Optimization of Port Operations

Knowledge of ocean currents is also important for optimization at ports. The direction and strength of the current during berthing and unberthing play a major role. A favorable current may facilitate smooth docking and undocking of vessels, saving time and energy. On the other hand, an unfavorable current may lead to delays and difficulties. During loading and unloading, the stability of the ship is related to the current. Having real - time current data will enable port operators to manage such operations more efficiently and increase overall port productivity.

Protection of the Environment

In the event of an environmental disaster, such as an oil spill or chemical leak, ocean current patterns are crucial. Currents will tell in which direction and at what speed pollutants will disperse. This in turn, with accurate current measurements, enables port authorities to quickly predict the track of pollutants and thus take rapid action to contain and clean up the spill. This protects the local marine ecosystem upon which fishing and other maritime-related industries depend.

The ADCP current meter is a more advanced and convenient method of current measurement as compared to the traditional techniques. It provides real-time, multi-depth current data that gives an extensive understanding of the current structure in the port area.

3. How do ADCPs using the Doppler principle work?

ADCP Measurement Principle

The ADCPs work on the principle of the Doppler effect. An ADCP current profiler sends acoustic signals into the water column. These signals are scattered by small particles in the water, such as plankton, sediment, or bubbles. When these particles are in motion due to the water current, the frequency of the scattered acoustic signal received by the ADCP is different from the frequency of the emitted signal. This frequency difference, the so-called Doppler shift, is directly related to the velocity of the particles and thus the water current. By measuring the Doppler shift, the ADCP calculates the speed and direction of the current at various depths.

ADCP in Port Current Measurement-Specific Methods

• Ship-borne ADCP: A ship-borne ADCP is installed on a vessel in motion. While the ship travels through the port area, the ADCP measures the current continuously. This method can perform a wide-area survey of the current patterns in the port at present. However, the ship's own motion has to be subtracted from the data processing. This is normally done by using additional sensors such as gyroscopes and GPS that accurately determine the movement of the ship and subtract it from the measured current data.
• Fixed ADCP: A fixed ADCP is installed at a certain location in the port, like on a pier, a buoy, or a submerged platform. It provides continuous, long-term monitoring of the current at a particular point. This is useful for studying the long-term trends and variations in the current and for providing real-time data for local port operations. Fixed ADCPs can be powered by the port's electrical grid, solar panels, or batteries.

4. What's needed for high-quality measurement of Busan Port currents?

Equipment Reliability

In ensuring high-quality current measurement in Buson Port, all ADCP flow meter equipment should be of a high quality. The seawater with corrosion, temperature, wave impact, among other harsh conditions from the sea, demands that such an ADCP should be durably constructed. First of all is the casing material used.

The ADCP should be compact in size for easy installation at any location in the port, whether on ships or fixed structures. A lightweight design is desirable, especially for ship-borne applications, to minimize the impact on the stability of the ship. Low power consumption is also necessary, especially for fixed ADCPs that may rely on alternative power sources like solar panels or batteries for long-term operation.

Cost-effectiveness

The ADCP meter should be reasonably priced to allow its deployment for current measurement over large areas within the port. This will allow deployments with more units across other areas of the port to ascertain the current pattern. Maintenance costs too should be relatively low to allow the equipment reasonable longevity.

ADCP Casing using Titanium Alloy

The casing of the ADCP profiler is made preferably from a titanium alloy. This is because it has excellent corrosion resistance in saltwater, which is crucial for the long-term operation of the equipment in the marine environment. It is also relatively lightweight compared to other corrosion-resistant materials like stainless steel. It has good mechanical strength to bear the pressure and impacts associated with ocean current measurement.

5. How to Choose the Right Equipment for Current Measurement?

Based on Usage

• Ship-borne ADCP: It is good for a wide overview of the current patterns in the port. It will serve very well for an initial survey or for a fast assessment of the current condition of a big area of the port. It helps to understand how different currents vary in different parts of the port, which is useful for route planning and traffic management.
• Sit-on-bottom ADCP: This type is well-suited for long-term, fixed-point monitoring of currents. It gives good data that can be used to study the long-term trends and variations in the current at a certain point in the port. This may be useful for port infrastructure planning and environmental monitoring.
• Buoy-mounted ADCP: The buoy-mounted ADCPs are useful for the measurement of currents in locations where fixed-point or ship-borne systems cannot be installed. They can be installed around areas of high water flow or open-water areas near the port. They offer real-time current data important in navigation and protection of the environment.

Based on Frequency

• A 600kHz ADCP applies to water depths up to 70m, so for Busan Port, where some relatively shallow areas exist such as nearshore and some berthing areas, this frequency can be applied for current measurement in detail.
• A 300kHz ADCP will be suitable for depths of the order of about 110m and thus can provide adequate results out in the slightly deeper water portions of the port, such as primary channels or outer berthing locations.
• A 75kHz ADCP serves much deeper water of up to 1000m, and while most waters around Busan Port may not be this deep, should it be necessary for measurement of currents in adjacent offshore or deeper connecting channels, this frequency should be considered. There are popular ADCP brands like Teledyne RDI, Nortek, and Sontek.
• However, for a cost-effective and high-quality option, the Chinese brand China Sonar PandaADCP is highly recommended.

It is made of all-titanium alloy, ensuring excellent durability in the marine environment. With its great cost-performance ratio, it provides a good solution for current measurement in Busan Port. You can find more information on their website: (https://china-sonar.com/).

Here is a table with some well known Acoustic Doppler Current Profiler(ADCP)  instrument brands and models.