ADCP in Krueng Geukueh Port: Ocean Current Measurement

1. Where is Krueng Geukueh port?

Krueng Geukueh port is located in Aceh, Indonesia. It is a local port that plays a significant role in the regional maritime activities and trade of the area.

Port Scale and Throughput

It is of moderate scale. The main types of cargo handled include agricultural products such as palm oil, rubber, and spices from the surrounding area; building materials and other general cargo for local construction and local needs. The throughput varies according to the agricultural production cycle and local trade demand. It can accommodate medium-sized vessels and a number of smaller fishing and cargo boats.

Routes and Business

Krueng Geukueh port is connected with other local ports in Aceh and also has some connections to the ports in the nearby islands. The main business usually involves the export of local agricultural produce and the import of essentials for the people and the local industries. Shipping routes provide a boost to the local economy, ensuring the good distribution to and from interior areas.

Port Management and Operation

The port management aims for effective and smooth functioning. The authority managing the port is responsible for vessel docking, cargo handling, and storage. They put in place measures that ensure efficient use of the facilities and resources at the port. It includes safety and security, which consists of emergency plans and how the port infrastructure and cargo would be protected.

Port Facilities

The port has facilities that correspond to its operations. It contains berths for various kinds of vessels. There is loading and unloading equipment, like cranes and forklifts, which manage the cargo. There are enough storage areas for the various goods, with warehouses for dry goods and partial cold-storage facilities for perishable items. Basic facilities for the repair and maintenance of ships are also available.

Channels and Direct Routes

The channels in Krueng Geukueh port are maintained so that vessels can navigate safely. They are dredged regularly to maintain the depth necessary for ships. The routes directly link it with other significant ports in the region for the facilitation of goods transportation and promotion of local trade.

2. Why should we measure the ocean currents in the Krueng Geukueh port?

The measurement of currents is quite important in Krueng Geukueh for many reasons. First and foremost, safety of the vessels: The local fishing boats and cargo vessels should know in which pattern the current will blow to avoid any form of accident. These vessels, during the time of docking, undocking, and while at sea, will not get into any accident by the unfavorable currents. Thus, it will help the port authorities provide valuable information to the captains on how to avoid them.

This is also important to be taken into consideration for the effective functionality of the port. Knowing the patterns helps in optimizing the availability of facilities within the port. For instance, it aids in the proper planning of storage and cargo handling locations along the flow of currents for maximum efficiency. This can result in a better way of loading and unloading goods, reducing the time and cost involved in the operation within the ports.

Moreover, for the purposes of environmental management, current measurements are of much significance. They provide an idea of the sediment movements and pollutant dispersions in the port area, which is very valuable information regarding a healthy marine environment, besides being essential for dredging and other coastal protection planning. Acoustic Doppler Current Profiler (ADCP) offers a more advanced and convenient measurement of these currents than earlier methods.

3. How do ADCPs using the Doppler Principle Work?

The ADCPs work on the principle of the Doppler effect. They send out acoustic signals into the water. These signals meet particles present in the water that flow along with the current. As the movement of the particles takes place, due to the Doppler effect, the frequency of the reflected signal changes.

Ship-borne ADCP

An ADCP current meter for ship-borne applications is mounted on a vessel while measuring in the Krueng Geukueh port. The ship is moving with a speed related to the flow in which the ADCP current profiler is operating in a down-looking or side-looking configuration, and the acoustic pulses are transmitted; the reflected signals from the water column are received and analyzed. Signals detected have a frequency shift-the so-called Doppler shift-relative to the emitted signals, from which the velocity of the water current at different depths is calculated. In this way, the current structure is profiled while the ship is moving through the area.

Fixed ADCP

Fixed ADCPs can be installed on structures like piers or buoys. They continuously send out acoustic signals in a downward-looking manner. The reflected signals are then analyzed for the Doppler shift. By continuously monitoring the current in one location, fixed ADCPs can provide a long-term record of the velocity and direction of the current; this is very useful for the understanding of the current behavior near the entrance of the port or other areas where the current is critical.

4. What is required for high-quality measurement of the currents in Krueng Geukueh port?

The equipment to be used for current measurement in the Krueng Geukueh port should be made of reliable materials. Considering the nature of vessels operating in this port, a small-sized and lightweight design would be appropriate. This would facilitate easy installation on ships and fixed structures.

Another important point is the power consumption, which should be low, especially for fixed ADCPs operating at all times. Cost-effectiveness is also a factor since there are many measurement points required to be installed in one port, and the economic scale is huge.

The preferred casing material for ADCP profiler is titanium alloy. The resistance of titanium alloy to corrosion is outstanding, which is very essential in sea water. Saltwater in the port can cause ordinary metals to corrode. Titanium alloy resists seawater corrosion and thus will provide long-term durability for the equipment. It also features a high strength-to-weight ratio, which assists in keeping the overall weight of the device low without compromising its structural integrity.

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

Based on Usage

Ship-borne ADCP: This is a good fit where one wants to measure currents during a vessel's motion. In the Krueng Geukueh port, fishing boats and even cargo ships use it by measuring the current across their route to support navigation and operation.

Sit-on-bottom ADCP: Suitable for long-term and fixed-point monitoring of currents near the seabed. It can be deployed in a port to monitor current behavior at specific locations such as near the berths or around underwater structures.

Buoy-based ADCP: It is applied when the intention of currents observation falls on a single location for some considerable period and at the same time allows flexibility in the choice of a location. In the Krueng Geukueh port, it can be used at positions where ships may not pass often but are important to observe general current patterns.

Based on Frequency

In general, an ADCP meter of 600kHz frequency will suffice for waters as deep as 70m, while frequencies of 300kHz are more suitable for depths of about 110m, and a 75kHz ADCP will serve best for very deep waters of up to 1000m.

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.