ADCP's Application to Ocean Current Measurement in Gandía Port

1. Where is Gandía Port?

Gandía Port is located on the eastern coast of Spain, along the Mediterranean Sea. It is a port serving both local and regional maritime needs.

Port Scale and Throughput

The port scale is relatively middle-sized in terms of its throughput. In addition, it handles cargo such as agricultural products stemming from the rather fertile surrounding areas, general cargo, and some tourism-related traffic simply due to proximity to popular beaches and resorts. It handles considerable volumes annually that are important for the local economy and also deals with a good number of smaller to medium-sized vessels.

Routes and Business

Gandía Port is well connected to the regional shipping routes. This is used to transport locally produced goods to other Spanish ports and has small trade links up with other nearby Mediterranean destinations. This involves exporting produce of the surrounding countryside and the importation of goods for consumption by the local communities and their industries. In addition, nautical tourism has created further advantages for the port, including places for mooring yachts and the possibility to dock small-scale cruise ships.

Port Management and Operation

This port management is concerned with smooth and safe operations. Through the control of traffic, the port authorities manage the movement of ships and boats in its system. The basic infrastructure to be provided by a port authority includes the dock and storage areas with their basic cargo-handling equipment. This helps in controlling any environmental effects and provides safety measures within the port area and its waters.

Port Facilities

Facilities in this port include the fishing docks serving the local fishing fleet, yacht and small- to medium-sized commercial vessel berths, and storage areas for general cargo, refrigerated cargo, project cargo, and agricultural products. Appropriate loading and unloading equipment includes those suitable for general cargo and agricultural products. Tourist information facilities and waterfront cafes and restaurants complement the port's tourist facilities.

Channel and Direct Navigation

Gandía Port has a channel to the sea. Navigation in the area is relatively easy, with the help of navigation aids such as buoys and lights. There is the possibility of direct navigation to and from the port, which means that ships and boats can enter and leave the port smoothly.

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

Navigation Safety

Measurement of ocean currents is very important in Gandía Port for the purpose of navigation safety. This current pattern, understood properly, helps the captains of fishing vessels and small to medium-sized commercial ships to undertake their route planning more accurately. By doing so, the captains can avoid dangerous situations-such as being pushed onto rocks or other vessels-by knowing in which direction and at what speed the currents are moving. In the case of yachts and tourist boats, accurate current information ensures a more pleasant and safe sailing experience.

Efficient Port Operations

Accurate current measurement is necessary for the commercial activities of the port. Such a measurement will allow tugboats to give better assistance during the maneuvering in docking and undocking of ships. Moored vessels would also need to know the currents in order to know the proper mooring arrangements needed to keep the vessels from drifting and damaging the facilities in the port area or other boats.

Environmental Management

From an environmental point of view, it is important to understand the currents of the ocean for waste management and sediment control at the port. Currents can affect the dispersion of pollutants and the movement of sediments. By measuring the currents, the port can better manage waste disposal and prevent the accumulation of sediments that could reduce the depth of the channel or berths.

In principle, it is an ADCP current meter that makes measurements of these currents much more effective than traditional techniques.

3. How do Doppler principle using ADCPs work?

The principle behind ADCPs is the Doppler effect. They emit acoustic pulses into the water. These pulses interact with particles in the water, such as plankton, sediment, and other suspended material, through which the frequency of the reflected sound waves changes by virtue of the motion of these particles.

The ADCP measures the difference between the emitted and received frequencies and, by means of the Doppler equation, calculates the velocity of the particles causing this frequency shift. This velocity is related to the velocity of the water current. The ADCP current profiler can also measure the current velocity at different depths within the water column; it can thus provide a vertical profile of the current.

Ship-borne ADCP

An ADCP flow meter installed on a vessel is called a ship-borne ADCP. While the ship moves around the port area, the ADCP continuously emits and receives acoustic signals. The data collected during the movement of the ship provides a broad view of the current patterns in different parts of the port.

Fixed ADCP

Fixed ADCPs are installed at strategic points around the port, for instance, on the seabed near the docks or at the entrance of the channel. This kind of ADCP profiler provides the most continuous measurements of the currents at an individual point. They are very useful for monitoring the long-term current patterns, which may occur and affect everyday operations and the stability of the port's infrastructure.

4. What would high-quality measurement of currents require in the Gandía Port?

Reliable Equipment Materials

For any equipment, high-quality, current measurement will need reliable materials. This is for realizing such activities at the Gandía Port. For the material in the equipment to withstand the salty, corrosive nature of sea water, it would be important that it bear all elements of weather.

Small-Sized Equipment

A small-sized ADCP is preferable, which will provide ease in installation, especially in the relatively compact port facilities.

Light-Weight Design

The weight of the ADCP should be light to simplify the installation process and reduce the load on the installation structures.

Low Power Consumption

Another major factor is low power consumption. In a port environment, for instance, equipment that can operate all the time but without high-power consumption is more realistic.

Cost-Effectiveness

Cost-effectiveness is not less important either, as every port may want to deploy many units to accomplish full current measurement.

The casing of the ADCP meter is preferably made of titanium alloy. This material has excellent corrosion resistance and, therefore, is very well suited for the marine environment. In addition, it is strong and light and thus meets both the requirements for durability and easiness of installation.

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

Based on Usage Purpose

• Ship-borne ADCP: this is applied to ships and boats that would be moving around the port area, including fishing vessels, yachts, and small- to medium-sized commercial ships. This is used as a mobile method for measuring currents with applicability in defining general current patterns while the vessel is under motion.
• Bottom-mounted ADCP: It is appropriate for fixed-point monitoring near the docks, the channel entrance, or other critical areas of the port. It gives the current condition continuously at one location and forms part of the safety and operation of the port.
• Buoy-based ADCP: This can be used in areas where it is not convenient to install fixed-bottom or ship-borne ADCPs. It provides a floating option for current measurement and can cover areas in the open water of the port.

Based on Frequency

The choice of frequency depends on the water depth. In the case of Gandía port, a 600kHz ADCP should work very well in waters up to 70m deep. As a matter of fact, this instrument could be used for the shallower areas near the shore or inner parts of the port. A 300kHz ADCP would be suitable for waters up to 110 meters and could survey a wider depth range. A 75kHz ADCP provides better penetration for larger depths in general in the port area. With a greater range of nearly 1000m, ADCPs could serve the areas like an approach channel for much deeper water.

There are well-known ADCP brands like Teledyne RDI, Nortek, and Sontek. However, a Chinese brand, China Sonar PandaADCP, is also a great option. It is made of all-titanium alloy material, providing excellent durability and a high level of corrosion resistance. It also offers an attractive cost - performance ratio. You can visit their website (https://china-sonar.com/) for more details.

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