ADCP in Mongla Port's Ocean Current Measurement

1. Where is Mongla Port?

Mongla Port, which is located in the district of Bagerhat, Bangladesh, is one of the major seaports and a strategic gateway for the maritime trade in the southwestern area of Bangladesh. It lies close to the Sundarbans mangrove forest and extends further into the Bay of Bengal.

Port Scale and Throughput

Scale: The port is medium to large in terms of structure. It consists of several berths for cargo ships, with partial facilities for container ships and bulk carriers. The quay area is somewhat spacious, allowing loading and unloading operations to take place. There are storage facilities designed to manage various types of cargo, including agricultural products, jute, and other local commodities.

Throughput: Its yearly throughput is fairly sizeable given its stature in the region. The port plays a very significant role in the export of commodities such as jute, fish, and agricultural produce from the south - western regions of Bangladesh. Imports constitute construction materials, machinery and consumer goods for the local population and industries.

Routes and Business

Routes: Mongla Port is integrated into a system of shipping routes. It has connections with other Bangladeshi ports and also with the ports in neighboring countries like India and Myanmar. Internationally, it has trade links with ports in South-East Asia and the Middle East. These shipping routes become vital to the import-export business and carrying goods to and from the hinterland.

Business: The major business activities include cargo handling-related services for general cargo, fishing products, and agricultural produce. Additionally, it provides warehousing, logistics support, and customs clearance services. There is also significant business related to fishing, including facilities such as unloading, processing, and storing fish. The port also facilitates trade in local agricultural products and handicrafts.

Port Management and Operation

The port is controlled by a system governing the arrival and departure of ships, allocation of berth, and operations of cargo-handling. The management is fully aware of resource utilization and safety principles. They maintain safety measures with the view to safeguard the ships, cargo, and laborers. Environmental protection is reflected in order to reduce the possible effects of port activities on the local marine environment and the nearby Sundarbans.

These include procedures for handling emergencies such as cyclones, which are common in the region, and fires. Safety and security checks are also an important aspect of the facilities to ensure safety of goods and people. Environmental protection measures will entail methods of waste management and measures aimed at preventing pollution of the water and the mangrove ecosystem.

Port Facilities

Fishing-related facilities: Since fishing is very significant in the ports, it comprises fish-unloading docks, cold storage to preserve fish, and processing areas for fish. These facilities help with handling the catch related to fishing and maintaining the quality of the products that are derived from it.

Cargo - handling Facilities: There are cranes besides other loading - unloading equipment for handling general cargo and agricultural products. The storage areas are utilized for storing various types of cargo, from building materials to consumer goods.

Container Terminals: It has some limited container-handling capabilities. The terminals are equipped with necessary cranes and storage yards for containers.

Channel and Direct Shipping

Smooth passage is ensured by maintaining the channels of this port. It has direct shipping services with key regional and other international ports. These direct links give it an edge in competitiveness, a helper toward the smooth flow of goods.

2. Why should we measure Mongla Port's ocean currents?

Ocean current measurement in Mongla Port is very important. In navigation, correct current information is highly important to ships. Currents may affect speed and course, and in a port like Mongla, receiving vessels of different categories, the information allows the masters of the vessels to make precise adjustment accordingly. This helps in avoiding collisions and enables more efficient docking and undocking procedures. For instance, a cargo ship transporting agricultural products should be able to pass the port waters with a great deal of exactitude, for which knowledge of the currents is needed.

Cargo-handling operations depends on the flow of the ocean currents. Unstable or strong currents add difficulties to operating cranes and other handling equipment with full accuracy. Current measurements will enable the port authorities to plan cargo-handling operations in a way that takes into consideration current conditions to reduce the waiting time of ships and improve the overall work efficiency.

Ocean current measurement is also very important for environmental monitoring, as the current data would help predict the spread direction and speed of contaminants in the case of an oil spill or other pollutants. This will help the port take timely preventive and remedial measures to protect the marine environment and the adjoining Sundarbans mangrove forest. The ADCP current profiler is also more sophisticated, providing ease compared to the conventional techniques of measuring the currents, which helps ADCPs serve more usefully at Mongla Port.

3. How do the Doppler principle-based ADCPs work?

Principle of Measurement

Acoustic Doppler Current Profilers (ADCPs)  based on the working principle of the Doppler effect. If an acoustic signal is transmitted into the water by the ADCP doppler, then due to particles and other dissolved constituents of the water, the signal gets scattered. Since the water particles are in motion and carried away by the ocean current, the scattered signal frequency received back by the ADCP flow meter will be different from the transmitted frequency due to the Doppler effect. It will then be able to measure the frequency shift and hence the water particle velocity and the velocity of the ocean current accordingly.

ADCP in Port Ocean Current Measurement: Shipborne ADCP

Shipborne ADCPs are fixed upon ships. While the ship is moving around the Mongla Port area, ADCP continuously transmits and receives acoustic signals. With this, the ocean currents at different depths along the track of the ship can be measured. Data being collected can be used for analyzing current conditions in the area in which a ship is sailing, thus availing valuable information to ship navigation and operations. For example, the shipborne ADCP current meter can guide a fishing boat through the best path in the port waters.

Fixed ADCP

Fixed ADCPs are installed at fixed locations in Mongla Port, such as on piers or buoys. The fixed ADCPs remain in the same position and record the river currents regularly at the point from which they were installed. They can provide long-term and stable current data, useful for understanding the overall current patterns and their changes in the port area with time. For instance, a fixed ADCP flow meter near the cargo-handling area can provide currents data for better optimization of cranes operating there.

4. What does a high - quality Mongla Port current measurement require?

Equipment Requirements

Material Reliability: The equipment should be fabricated from very reliable materials. They have to be resistant to harsh marine conditions, like seawater corrosion, high humidity, and impacts from floating objects. For Mongla Port, which faces the Bay of Bengal and with cyclones a common factor, this is highly relevant in terms of material choice for good performance over a longer period.

Small in Size and Light Weight with Low Power Consumption: A small-sized and lightweight ADCP flow meter is preferred while installation and working, especially the shipborne ADCPs. Low power consumption enables the equipment to keep working longer without replacing the batteries frequently, with a high power supply of the equipment, which is very significant both for fixed and shipborne ADCPs. Considering the different types of vessels in Mongla Port, ease of installation and operation is a vital concern.

Low enough cost: It will allow the deployment of several ADCPs in various locations within the port, hence giving even wider current data coverage. There is a need to provide coverage for different areas in the port, and equipment that is not too expensive will therefore be highly welcome.

Advantage Using Titanium Alloy for ADCP Casing: Titanium alloy is a perfect material for ADCP doppler casing. Its great corrosion resistance and thereby the capability of withstanding the corrosive effect of seawater are outstanding. In the context of Mongla Port, the equipment can function continuously without degradation for a very long period of time in a secured, stable, and reliable way. It is of great strength-to-weight ratio, which means it can provide enough strength while keeping the weight relatively low; this meets the requirement of small size and light weight, thus facilitating the installation and operation of the ADCP profiler. Third, titanium alloy has good thermal stability, helpful for normal operating work in different temperature environments in the Mongla Port area.

5. How to Choose Right Equipment for Current Measurement?

According to the Use Purpose

Shipborne ADCP: When the measurement is to be done mostly on ships, one may go for shipborne ADCPs. With it onboard a ship, the unit can rotate while the ship is moving and measure currents at different locations around the port. Shipborne ADCPs may be installed on cargo ships and fishing boats that regularly come to Mongla Port in order to give current information in real time to enable safe navigation.

Sitting - Bottom ADCP: For long - term fixed - point monitoring of current at a specific location in the Mongla Port, sitting - bottom ADCP is a good choice. It is usually installed on the seabed and can continuously monitor the currents in its vicinity. For example, near the entrance of the port or at critical docking areas, sitting - bottom ADCPs can provide stable and long - term current data.

Buoy-type ADCP: It finds applications in cases where there is a need to monitor the currents at a particular area of the port in real time. The buoy will be floating on the water surface, while the ADCP doppler mounted on it measures the current around. In areas like the middle of the port or near fishing areas, it is possible to get useful current information from buoy-type ADCPs.

Selection Based on Different Frequencies

Different frequencies of ADCPs apply to different water depths. For example, the 600 kHz ADCP applies to water within 70 m. It can provide more informative data about the current in comparative shallow water areas. In Mongla Port, this could be useful near the shore or in shallower parts of the port area. The 300 kHz ADCP will be suitable for a water depth up to 110 m, while 75 kHz ADCP is suitable for much deeper water, up to 1000 m. This difference in frequency allows accurate measurement of currents at different Mongla Port depths according to the actual water depth conditions.

There are many well-known ADCP meter brands, which include Teledyne RDI, Nortek, and Sontek. For customers who are seeking economical options, it is highly recommended to use the Chinese brand called China Sonar PandaADCP. The material is all - titanium alloy; thus, the cost - performance ratio is beyond imagination. You can visit its website here: (https://china-sonar.com/).

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