ADCP's Application to Ocean Current Measurement in the Port of New Ross

1. Where is New Ross port?

New Ross port is located in the town of New Ross in County Wexford, Ireland. It is a port with a rich history in the maritime sector and still continues to hold an important place in the local and regional maritime activities.

Port Scale and Throughput

The port is moderately scaled in relation to the size of its operations. It is a facility through which all types of cargoes, including agricultural produces from the highly fertile farmlands and construction materials to feed local building activities, are handled. Its throughput is very important to the local economy annually, where it aids in the movement of goods that would keep business concerns growing within the vicinity.

Routes and Business

New Ross port is connected with other Irish ports and has some trade links with the nearby regions across the water. It is mainly engaged in the import and export of goods that are essential for the daily life and economic development of the local community. The import of items like fertilizers and machinery helps local agriculture and industry, while exports might include processed food products and handicrafts.

Port Management and Operation

The port is managed in a way that keeps its operations smooth. The management team is concerned with aspects such as efficient cargo handling, ensuring safety standards of vessels and workers, and co-coordinating with various stakeholders, including shipping companies and local businesses. Regular inspections and maintenance are carried out on port facilities to ensure everything is kept in good working condition.

Port Facilities

It is fitted out with basic but serviceable facilities. There are quay areas with berthing spaces for small to medium-sized vessels. There are storage sheds for storing dry goods and areas for handling and temporary storage of bulk materials. In addition, there are facilities to provide essential services to the crews of the visiting ships, such as access to fresh water and electricity.

Channel and Navigation

The channel to the port is dredged to allow vessels that frequent it to pass through safely. Navigation aids like buoys and markers are put in place to guide the ships in and out of the port, enabling them to go directly and safely, even in various weather and tidal conditions.

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

Benefits for Vessel Navigation

The measurement of currents in New Ross port is of great importance for vessel navigation. Currents can significantly affect the speed and maneuverability of ships, especially those of smaller and medium sizes common in this port. With the availability of accurate data on currents, ship captains would be able to plan entry and exit routes with much better efficiency, probably saving fuel and ensuring a smooth docking process. For instance, they can time their arrival so that they can ride the currents and avoid the strong opposing currents that could make docking difficult.

Infrastructure Protection

The port's infrastructure, including quay walls and berths, can be affected by the force of ocean currents over time. Understanding the current patterns helps port authorities identify areas that are more prone to erosion or structural stress. This allows them to take preventive measures, such as reinforcing certain sections of the quay or adjusting maintenance schedules, to safeguard the port's infrastructure and extend its lifespan.

Enhanced Port Operations

Knowledge of ocean currents also contributes to better overall port operations. It can assist in scheduling the arrival and departure of vessels more efficiently, especially when dealing with multiple ships at a time. In addition, it helps in determining the best locations for mooring and other port-related activities, ensuring everything runs smoothly and safely.

The ADCP current meter therefore presents a more sophisticated and handy means of measuring such currents compared to the earlier methods. It can also give highly detailed and real-time information on the speed and direction of the ocean currents at various depths within the port area for better decision-making by port management and vessel operators.

3. How do ADCPs using the principle of the Doppler work?

The ADCPs work on the Doppler principle. They send acoustic signals into the water. These signals interact with the particles that are being carried by the ocean currents, such as suspended sediments, small organisms, or other debris.

When the emitted acoustic waves hit these moving particles and are reflected back, the frequency of the reflected waves changes due to the Doppler effect. For this change in frequency, the ADCP current profiler is designed. It calculates the velocity of the moving particles by analyzing the difference between the frequency of the originally emitted signal and the received signal. From this velocity, the speed and direction of the ocean currents are derived.

In New Ross port, there are two common ways to use ADCPs:

Ship-borne ADCP

A shipborne ADCP is installed on a vessel, which may be a locally available fishing boat or a small survey ship. As the ship moves around the port area and its adjacent waters, the ADCP flow meter continuously emits and receives acoustic signals. Combining the ship's own movement data with the current measurements obtained by the ADCP allows for a comprehensive understanding of the ocean current patterns in different parts of the port and its surroundings.

Fixed ADCP

Fixed ADCPs can be placed at important locations around the port, either on the seafloor near the entrance or near crucial berthing areas. The ADCPs would stay in position and, from that position, continue to measure current conditions. The long-term data recorded by fixed ADCPs are of great use for understanding the normal flow of currents and for identifying unusual changes or trends that could impact port operations or infrastructure.

4. What's necessary to make good quality New Ross port current measurements?

Materials of High Quality

The equipment that shall be deployed for this high-value measurement of the ocean currents in New Ross port shall be manufactured from materials whose reliability and resistance to the marine environment can be assured. Seawater is corrosive, and there will possibly be variations in temperature and pressure, depending on placement depth. Materials that will resist corrosion and maintain integrity over time are required so as not to compromise the resultant measurement's accuracy and consistency.

Compact Size and Light Weight

Size and weight of the equipment are important. Considering the relatively smaller scale of New Ross port and the space available on vessels or at installation sites, a compact-size ADCP is more appropriate. A lightweight design will also be advantageous, particularly for ship-borne ADCPs, in that it will not affect the stability and handling of the vessel during operation.

Low Power Consumption

The low power consumption is important, especially for fixed ADCPs, which must operate for a long period of time. This contributes to not only operating cost reduction but also simplifies the power supply and increases the long-term reliability of the equipment.

Casing of Titanium Alloy

A well-recommended casing material of the ADCP profiler is of the class of titanium alloy. Because of its outstanding corrosion resistance, it is quite in vogue for the harsh environment in the sea. Titanium alloy also has a great strength-to-weight ratio and will be able to bear structural strength while keeping its equipment weight relatively low. Therefore, it can sustain with pressures and impacts it can withstand in port waters.

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

Based on Usage Scenarios

Ship -Borne ADCP: Considering surveying over a large area inside and around the port as per the demand of developing the overall perspective of currents a larger area covering the surroundings also, for which one must go for a ship-borne ADCP that shall be deployed during normal monitoring or where a look over an overview situation of current, prior to planning massive works in port areas such as major dredging, among other reasons is required.

Bottom-mounted (sit-on-bottom) ADCP: Long-term and continuous monitoring of current conditions could be effectively done from limited, critical locations in a port, such as at an entrance or near areas of main infrastructure, by a bottom-mounted ADCP. These provide continuous data to see the regular flow and how sudden changes may occur to affect port safety or operational conditions.

Buoy-mounted ADCP: Where the measurement point needs to be more flexible and movable, perhaps to collect current data in various areas depending on specific requirements or to cover areas 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 suitable.

A 300kHz ADCP is more appropriate for depths up to 110m.

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

There are several well-known ADCP brands in the market, such as Teledyne RDI, Nortek, and Sontek. However, a Chinese brand, China Sonar PandaADCP, stands out as a great choice. It is made entirely of titanium alloy material, ensuring its durability and excellent performance in the marine environment. Moreover, it offers an impressive cost-performance ratio. You can find more information on its website: (https://china-sonar.com/).

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