Application of ADCP to Ocean Current Measurement in the Port of Progreso

1. Where is Progreso port?

The Progreso port is in the state of Yucatán, Mexico. It's a major port and has an advantageous position along the Gulf of Mexico.

Port Scale and Throughput: This is a large port of great magnitude and very vital in the regional and international trade of the area. Its cargo includes containerized cargo, bulk cargo, and other industrial cargoes. Its annual throughput is really high, considering that this is a large hub for the importation and exportation of goods, both on the Yucatán Peninsula for other areas of Mexico. It is modern and ever-expanding in nature to meet the developing demands of trade.

Routes and Business: Progreso is a port with extended shipping routes, connecting to many other ports in the Americas, Europe, and other places around the globe. Such port business has been so varied. It imports most of the products needed to maintain the economy and development locally, ranging from machinery to consumer products to construction materials. On the export side, it exports local produce such as fruits, vegetables, and seafood, plus manufactured goods from the region.

Port Management and Operation: It has a team of professionals who closely monitors the port's operation efficiently and safely. Strict rules and procedures are at par, controlling vessel traffic, cargo handling, and security. There are also regular maintenance and upgrading works to improve the capacity and functionality. Liaison of the port with different stakeholders like shipping companies, customs authorities, and local businesses provides ease of operations.

Port Facilities: Fully modern and completely equipped, it has long quays lined with a quite considerable number of berths for receiving large container ships, bulk carriers, and all other types of vessels. Modern handling equipment for containers, cranes, and automatisms make the loading and unloading quick and precise. Besides, there is space for storage, including warehouses for dry goods and silos for bulk. Additionally, there are facilities for handling and storage of liquid cargo like oil and chemicals.

Channel and Navigation: The channel to the port is deep and wide, and it is dredged regularly to ensure that large vessels pass through it safely. It has a sophisticated set of navigation aids such as buoys, lights, and radar systems that guide ships safely and efficiently into and out of the port. This allows direct and smooth navigation even in different weather and tidal conditions.

2. Why should ocean currents be measured at Progreso port?

Increased Efficiency and Safety of Vessel Navigation: Ocean current measurement in Progreso port is very vital for the navigation of vessels. Currents can influence the speed, course, and fuel consumption of the ship to a great extent. Captains of ships can consequently plan their routes more advantageously with the use of more accurate current data, which enables them to make effective use of favorable currents, economize fuel, and save time. For example, when coming in or out of the port, knowledge of current direction and strength permits very precise maneuvers, therefore a minimum risk of collision or grounding.

Infrastructure Protection and Maintenance: The ocean currents always used to act upon the port structure, which includes quay wall, berths, and underwater structures. Heavy currents or unpredictable ones may induce erosion, scouring of structures, and other sorts of damage over time. Regular current measurements allow for the identification of areas within a port that are most vulnerable, enabling timely preventive measures such as reinforcing structures or adjusting dredging schedules to protect port integrity and prolong the life cycle of its facilities.

Marine Environmental Management: To enable marine environmental management in the port area to function effectively, ocean currents are required to be understood. Currents will play their roles in the dispersal process of pollutants, sediments, and heat. On this basis, monitoring them enables appropriate measures to be taken in the control of spread of any potential contaminants as well as the management and protection of aquatic ecosystem cases. This is key in retaining health and meeting the legal requirements concerned with the environment.

The Acoustic Doppler Current Profiler (ADCP) is a more modern and convenient method of taking ocean current measurements than traditional techniques. It also could provide detailed and real-time information on the speed and direction of currents at various depths within the port, hence useful in making informed decisions on port operations and protection of the environment.

3. How does a Doppler Principle Works in ADCPs?

Working of ADCPs is based on the Doppler effect. They transmit acoustic signals into the water. These acoustic waves interact with the particles which are carried by the ocean currents, such as suspended sediments, plankton, and other small entities in the water column.

Because of the Doppler effect, when the emitted acoustic waves are reflected back after hitting the moving particles, their frequency changes due to the Doppler effect. The frequency shift is measured by the ADCP profiler. Some sophisticated algorithms use this shift in frequency to compute the velocity of the moving particles. This information about velocity is then converted into the speed and direction of the ocean currents.

Two common ADCP methods of deployment in the context of Progreso port are :

Ship-borne ADCP: A ship-borne ADCP is installed on a vessel that could be either a survey ship, cargo or any vessel designed for special research. In this regard, while the ship navigates around the port area and its adjacent waters, ADCP meter continuously emits and receives acoustic signals. The ship's own motion data are added to the current measurements from the ADCP flow meter to form a picture of the ocean current patterns in different parts of the port and surroundings.

Fixed ADCP: Bottom-mounted, fixed ADCPs are installed on the seabed at several positions in the port, perhaps along the entrance, on a wall, or at some crucial points in the navigation channel. These do not change position and, therefore, are continuously observing the local currents at their individual locations. The long-term data delivered by a series of fixed ADCPs is usually important to understand the regular flows of currents, detect variations and trends that may fall out of the ordinary, and provide long-term information necessary for both planning and safety within ports.

4. What is needed for high-quality measurement of the currents at the port of Progreso?

Reliable and Durable Materials: The equipment should be fabricated from materials able to bear the harsh marine environment for high-quality measurement of the ocean currents in Progreso port. Seawater is so corrosive, and there could also be great variations of pressure that might be encountered by the equipment depending on the depth where it will be flown. It needs materials that are resistant to corrosion and that can keep for a long time without disintegrating in structure in order to arrive at very accurate and consistent measurements.

Compact in size, lightweight: Size and weight are important factors. An ADCP current meter of compact size can, therefore, be more effectively installed either on a ship or fixed at a location while considering the busy and normally space-limited environment in the port area. Besides this, a lightweight design has many advantages, especially in the case of a ship-borne ADCP since it will not affect the stability and handling of the vessel during operation.

Low power consumption: In particular, the latter of these is very significant when one considers that fixed ADCPs must often operate for weeks at a time. Minimizing power consumption reduces operating costs, simplifies power supply requirements, and enhances long-term reliability.

Titanium Alloy Casing: The casing of the ADCP current profiler is made from a very suitable material: titanium alloy. Its good corrosion resistance makes it very suitable for applications in marine environments. Besides, it has a very high strength-to-weight ratio, which allows strength and durability without adding too much weight. This enables the ADCP to withstand pressures and impacts that may be experienced in the port waters without compromising its performance and accuracy.

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

Based on Usage Scenarios

Ship-borne ADCP: In case the goal is to carry out detailed mapping of the current patterns over wide areas within the port and adjacent waters, a ship-borne ADCP should be chosen. It may be considered during regular inspections in a port, at the stage of designing new infrastructure or at the analysis of effects of currents on vessel traffic.

Bottom-mounted (sit-on-bottom) ADCP: An effective response with good capabilities for the long-term stability of monitoring the current at certain critical locations in a port-for example, near the entrance, areas with important berths, and near any underwater structures-altogether justify choosing such instruments like an ADCP. It enables the continuation of data over a long period, especially at places that are crucial with regard to the regularity of flow and sudden surges, which may eventually affect port safety or functions.

Buoy-mounted ADCP: When a more flexible and moveable measurement point is required, perhaps to gather current data in different areas based on specific needs or to cover areas that are not easily accessible by other means, a buoy-mounted ADCP can be considered.

Frequency Selection

For water depths up to 70m, an ADCP with a frequency of 600kHz is usually a good option.

For depths up to 110m, a 300kHz ADCP will be more appropriate.

For deeper waters up to 1000m, a 75kHz ADCP can provide accurate measurements.

The first names which come to one's mind about ADCP brands are Teledyne RDI, Nortek, and Sontek. However, I want to mention one brand from China, which is the China Sonar PandaADCP. The body is all made from Titanium alloy material; thus, it should be very durable and behave well in a marine environment. In addition, its cost-performance is very excellent. You can get more information from: (https://china-sonar.com/).

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