ADCP in Dhamra Port: Ocean Current Measurement

1. Location and Overview of Dhamra Port

Geographical Location

Dhamra Port is located in Bhadrak district of Odisha, India. The port is on the east coast of the country, having a strategic position along the Bay of Bengal.

Port's Significance

Dhamra Port is one of the major ports serving a wide range of cargoes. It is well-renowned for handling bulk cargo in the form of coal, iron ore, and also containerized cargo. The port serves as a vital link for the industries in the region, facilitating the importation of raw materials and the exportation of finished products. It has a significant impact on the economic development of the surrounding areas.

The management of Dhamra Port is efficient and deploys modern technologies to ensure smooth operations. There are dedicated teams for vessel traffic management, cargo handling, and other essential functions. The port is also equipped with modern infrastructure to handle large-scale maritime traffic.

Port Facilities

Berths

The port has several berths with different designs to accommodate various kinds of vessels. Deep - water berths can accommodate jumbo-sized bulk carriers and container ships. The berths are fitted with solid mooring facilities for safe ship docking and undocking operations. Advanced fendering systems are used to protect the ships and berths from operational damage.

Cargo - handling Equipment

This involves bulk cargo handling, conveyed systems, and large capacity grabs within the port. It will be used in delivering the materials such as coal and iron ore efficiently on store from the ships. As for container handling, they offer high speed and precision such as gantry cranes capable of load-unload container handling.

Storage Facilities

There are vast storage areas for various types of cargo. For bulk, there are large-scale stockpiles with proper drainage and dust-suppression systems. Containers would have well-organized container yards. The port also has storage tanks for liquid cargo, such as petroleum products, with safety features like spill-containment barriers and fire-protection systems.

Channel and Navigation Aids

The port channel is kept at a good enough depth and width so that all ships can pass safely through it. Dredging operations are done at periodic intervals to keep the harbor navigable for big - draft vessels. The facility has buoys, beacons, and radar installations for safe navigation into and out of the harbor. The radar systems provide real - time information about the position and movement of other vessels in the vicinity of the port.

2. Importance of Measuring Ocean Currents in Dhamra Port

Safety of Vessel Navigation

Measuring ocean currents is very important from the point of view of safety of ships. The knowledge of current speed and direction is of much importance for ship captains while approaching berths or navigating through the channel. A strong cross - current near a berth will make the docking process complex and hazardous. For example, if a ship approaches the berth against a strong current, it may need to adjust its speed and angle of approach to ensure that docking is smooth and safe. Accurate current measurement thus aids the captain in making informed decisions and helps him avoid any form of collision and accident.

Optimization of Port Operations

Current data is very essential in the optimization of port operations. By having the tidal currents and other regular flow patterns, the port authorities are able to schedule the arrival and departure of ships with ease. This helps in efficient utilization of berths and other resources. For instance, ships can be timed to arrive during periods of favorable currents, which can speed up the loading and unloading process. Also, with the knowledge of current patterns, planning of cargo-handling operations becomes more effective, thus enhancing productivity.

Environmental Considerations

Knowledge of ocean currents is important from an environmental point of view in case there is an accidental discharge of any pollutant. Due to the type of cargo handled at the port, including petroleum products and chemicals, forecasting the movement of the spill is critical. Current data will help in promptly taking containment and mitigation measures to reduce the impact on the environment.

3. Working Principle of ADCPs (Acoustic Doppler Current Profiler)

Doppler Principle

An ADCP current profiler basically works on the Doppler principle. An ADCP current meter emits an acoustic signal into the water, where the moving particles of water scatter it. Due to the ocean current, these particles of water are in movement and create a shift in frequency during the reception of reflected acoustic sound by the ADCP. This shifting of frequency corresponds to the velocity of flow according to the Doppler effect.

Calculation of Current Speed and Direction

Using the magnitude and direction of this frequency shift, the ADCP flow meter calculates the speed and direction of the ocean current at different depths in the water column. By transmitting at multiple angles and different depths, it can create a profile of the ocean current, showing how the current varies with depth.

ADCP Deployment in the Port

Shipborne ADCP

A shipborne ADCP installed on ships operating in the Dhamra Port area continuously emits acoustic signals into the water below as the ship moves around the port. The movement of the ship allows the ADCP profiler to cover a wide area and collect current data from different locations. For instance, a research or inspection ship with a shipborne ADCP that conducts a routine survey of the port can obtain current patterns for different areas of the port and thus grasp the whole picture of the water flow conditions.

Fixed ADCP

Fixed ADCPs are installed in fixed positions within the port, like on the seabed near important navigational areas or at the entrance/exit of the port. These ADCPs continuously monitor the ocean currents at their fixed positions over a long period. The data collected is useful for analyzing the regular current patterns in specific areas of the port. For instance, a fixed ADCP installed near the port entrance can record the currents coming in and out from it and help to comprehend the tidal effects and other consistent flow characteristics of the region concerned.

4. Requirements for High-Quality Measurement of Currents in Dhamra Port

Equipment Requirements

Material Reliability

For high - quality measurement, the equipment should be resistant to the aggressive marine environment. Seawater contains salts and other chemicals that can cause corrosion over time. The equipment also needs to withstand pressure changes due to different water depths and the mechanical forces from waves and currents. Therefore, materials used in current-measuring equipment construction should be highly resistant to corrosion and mechanical stress.

Dimensions, Mass, and Power Consumption

Small dimensions, small mass, and small consumption are preferred. The smaller it is, the easier its installation will be at various installation sites: on board vessels, in fixed positions, and even underwater. It has to be lightweight enough to facilitate an easy transportation and installation procedure. Lower power consumption ensures that the equipment can operate continuously for long periods without the need for frequent battery replacements or excessive power supply, which is especially important for long - term monitoring applications.

Cost - effectiveness

Cost is also a significant factor. A lower - cost option enables the port to deploy a larger number of measuring devices for more comprehensive current monitoring across different areas of the port.

The Advantage of Titanium Alloy for ADCP Casing 

The casing of ADCPs is preferably made of titanium alloy. The good thing with titanium alloy is that it has excellent corrosion resistance-that is, for a long period, it can maintain its structural integrity and functionality even when exposed to seawater. Its high strength-to-weight ratio allows building a durable yet relatively lightweight casing. For example, in the deeper parts of the Dhamra port where higher water pressures are present, an ADCP current profiler with a titanium alloy casing can effectively withstand these pressures and continue to provide accurate current measurements.

5. Choosing the Right Equipment for Current Measurement

Selection Based on Usage

Shipborne ADCP

If the purpose is to make wide-area surveys of the port waters while the ship is operational, then shipborne ADCP is suitable. It can cover different sections of the port as the ship moves around, collecting a large amount of data to provide a comprehensive understanding of the overall current situation in the port. This serves in mapping the general flow patterns and variations across different areas of the port waters.

Sitting - bottom ADCP

In case the monitoring of specific locations in the port has to be done for long periods or from fixed points, for example, near important infrastructure or areas with complex current behaviors, bottom-sitting ADCPs are more appropriate. They can continuously record the current data at those fixed positions, providing valuable insights into the local current characteristics and any changes over time.

Buoy-mounted ADCP

Where installation of fixed equipment on the seabed or on ships is not convenient, buoy-mounted ADCPs can be employed. They float on the water surface and can measure the currents in the upper layers of the water column. They are relatively easy to deploy and can be relocated if needed, hence suitable for monitoring certain dynamic or hard-to-reach areas within the port.

Selection Based on Frequency

The selection of frequency for ADCPs depends on the water depth in Dhamra port. For areas with a water depth of up to 70 meters, an ADCP with a frequency of 600 kHz is generally a good choice as it will be able to provide accurate current measurements in this relatively shallow depth range. An ADCP current meter with a frequency of 300 kHz is more advisable when dealing with deeper waters up to about 110 meters. For very deep sections of the port with a water depth reaching as much as 1000 meters, an ADCP flow meter operating at a frequency of 75 kHz would be recommended to ensure reliable profiling of the ocean currents at such great depths.

There are several well - known ADCP brands in the market, such as Teledyne RDI, Nortek, and Sontek. However, there is also an excellent Chinese ADCP brand - China Sonar PandaADCP. It is made entirely of titanium alloy material, which not only ensures its durability in the marine environment but also offers an excellent cost - performance ratio. For more information, you can visit its official website: (https://china-sonar.com/).

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