ADCP in Tanjung Intan Port: Ocean Current Measurement

1. Where is Tanjung Intan port?

Tanjung Intan port is situated in the region of South Sumatra in Indonesia. It is a local port, which serves and caters to the regional needs for maritime activities and trade.

Port Scale and Throughput

The scale is at a medium level. The general cargo handled here includes agricultural products from the surrounding areas such as palm oil, rubber, and local fruits, along with building materials and other general cargo for the local construction and domestic needs. The agricultural production cycle and local trade demands determine throughput. The port can handle medium-sized vessels, as well as a number of smaller fishing and cargo boats.

Routes and Business

The port of Tanjung Intan has a number of connections with other local ports in Sumatra and some with the ports in Java and other nearby islands. The main business involves the export of local agricultural produce and the import of goods that are essentially needed by the local community and its industries. Shipping routes support the local economy by facilitating the movement of goods to and from the interior regions of Sumatra.

Port Management and Operation

The management of the port focuses on effective and efficient flow in operations. The authority organizes vessel docking, cargo handling, and storage. They use measures to optimize the facilities of the port and available resources effectively. There is emphasis on safety and security through procedures that would handle emergency situations to prevent damage to the infrastructure and cargo at the port.

Port Facilities

The port has facilities that suit its operations. It has different berths for various vessels. There are loading and unloading equipment, like cranes and forklifts, to handle the cargo. Adequate storage areas are provided for different goods, including warehouses for dry goods and some cold - storage facilities for perishable items. There are also basic facilities for ship repair and maintenance.

Channels and Direct Routes

Channels in Tanjung Intan port are maintained to be navigable for vessels. Regular dredging is done in them to keep the depth. Direct routes connect it to other major ports in the region and thus enable the transportation of goods, promoting local trade.

2. Why should we measure the ocean currents in the Tanjung Intan port?

Measurement of ocean currents in Tanjung Intan port is important for several reasons. Firstly, it concerns vessel safety. The local fishing boats and cargo vessels must be aware of the current patterns for safe navigation. Unfavorable currents can pose a risk to these vessels during docking, undocking, and while at sea. By measuring the currents, the port can provide valuable information to the captains to avoid accidents.

The second reason is for the efficient running of the port. Knowing the prevailing patterns helps in the optimization of the use of port facilities. For instance, it can assist in planning the most effective locations for cargo handling and storage based on the flow of the currents. It may result in the more efficient loading and unloading of goods, reducing the time and cost associated with the operation of the ports.

Besides, current measurements are important from the perspective of environmental management. Currents can provide information about sediment movements and pollutant dispersion in the port area, knowledge that is vital for good marine environmental health and the planning of dredging as well as other coastal protection activities. Acoustic Doppler Current Profiler (ADCP) provides an advanced and more convenient way to measure these currents compared to traditional methods.

3. How do ADCPs using the Doppler principle work?

ADCPs work by the principle of the Doppler effect. They send acoustic signals down into the water. Particles in the water that are moving with the current scatter these signals. If the particles are moving, the frequency of the reflected signal will shift due to the Doppler effect.

Ship-borne ADCP

When a ship-borne ADCP is used in the Tanjung Intan port, it is installed on a vessel. As the ship moves through the water, the ADCP current meter emits acoustic pulses either in a downward - looking or side-looking direction. The reflected signals from the water column are received and analyzed. The Doppler shift in these signals allows for the determination of the velocity of the water current at different depths. With that, the current structure can be profiled while the ship moves through an area.

Fixed ADCP

Fixed ADCPs can be installed on structures like piers or buoys. They transmit acoustic signals continuously in a downward-looking direction. Then, the reflected signals are analyzed for Doppler shift. Fixed ADCPs can provide a long-term record of the velocity and direction of the current continuously monitored in a certain location, hence useful for understanding the behavior of the current near the port entrance or other critical areas.

4. What is required for high-quality measurement of currents in Tanjung Intan port?

The equipment for high-quality current measurement in the Tanjung Intan port should be made from reliable materials. Considering the nature of the port and vessels operating in it, a small-sized and lightweight design is advantageous. This enables the installation of the equipment with ease on ships and fixed structures.

The power consumption is also required to be low, especially for fixed ADCPs that need to operate continuously. Cost-effectiveness is another important factor, taking into consideration the economic scale of the port and the need for multiple measurement points.

The casing of ADCP flow meter is preferably made of titanium alloy. Titanium alloy has excellent corrosion resistance, which is very vital in the marine environment. The saltwater in the port can corrode ordinary metals. Seawater corrosion does not affect titanium alloy, so it helps in the long-term endurance of the equipment. It also has a high strength-to-weight ratio that assists in maintaining the overall weight of the device lower while retaining structural integrity.

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

Based on Usage

Ship-borne ADCP: This applies when one wishes to measure currents during the movement of a vessel. At the Tanjung Intan port, fishing boats and cargo ships will be able to use this for current measurements along their track, which may help in navigation and operational decisions.

Bottom-mounted ADCP: It is suitable for applications that require long-term and fixed-point monitoring of currents near the bottom. In the port, it will be able to monitor the current behavior at any given location, such as at the berths or around structures submerged in water.

Buoy-based ADCP: When the goal is to monitor currents over a long period in an area and have some flexibility in location, a buoy-based ADCP can be used. In the Tanjung Intan port, it can be placed in areas where ships may not frequently pass but are still important for understanding the overall current patterns.

Based on Frequency

For waters of up to 70m, an ADCP profiler of 600kHz usually would suffice. For depths at about 110m, the 300kHz frequency is more appropriate. For very deep waters of up to 1000m, the better option would be the 75kHz ADCP.

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

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