ADCP in Xiamen Port's Ocean Current Measurement

1. Where is Xiamen Port?

Located in China, Xiamen Port is an important port. It is large in scale with big throughput. It is a major transport node, which has a very important position in the Southeast coast.

It has good terminal facilities with regard to cargo handling, including container terminals with modern machinery for loading and unloading. It consists of a number of berthing facilities that are able to hold vessels of different sizes, ranging from small vessels operating on the coast to the largest international container carriers.

All things considered, with its size and throughput taken into consideration, Xiamen Port has been developing steadily for many years. It handles considerable amounts of containers, general cargo, and liquid bulk cargo with an annual throughput ranking among the top positions in China.

Route-wise, Xiamen Port has enormous domestic and international shipping routes: it connects most of the big ports around the globe for international trade, and it has regular domestic routes along the coast of China to make goods transportation smooth within the nation.

The management is very effective, as is the operation of the port. Within the ports, there exist professional port management teams that ensure all activities are done in order. They are responsible for berth allocation, supervision, handling cargo, and ensuring that the operations within the ports are safe. Advanced information systems also exist within the facility to handle shipping schedules, cargo tracking, and other related operations.

The channels in Xiamen Port are well-maintained to ensure safe passage for the ships. Besides, the port has directly opened shipping routes with the majority of international destinations, which greatly improves the efficiency of international trade and transport.

2. Why should we measure the ocean currents in the Xiamen Port?

The measurement of ocean current data in Xiamen Port will bear a series of critical implications for port operation and management. Ocean current understanding may enable ships to adapt navigation paths and speeds in the interests of safe shipping. Strong ocean currents may have an impact on a ship's stability and maneuverability, while the accuracy of current data allows captains to make more appropriate decisions during voyages and reduces the chance of accidents that might involve collisions with other ships or running aground.

Second, the information on ocean currents is quite helpful in port operations, regarding cargo handling. Especially in handling cargo on and off the vessel, when the cargo handled is large or of heavy-duty type, the action of ocean currents should be considered concerning the stability of the ship itself and the operating handling equipment on it. Accurate current data will allow for optimizing the process of cargo handling to make it more efficient and reduce potential losses.

Besides that, it gives references to the ocean current data in planning and constructing the port infrastructure. It may be used to determine the scale and layout of port facilities such as designing breakwaters and finding locations for new berths. With a long analysis of ocean currents, it can help the port adapt to the marine environment much better and ensure the long stability and development of the port.

Advanced measurement methods are adopted in modern port management. Compared with the traditional measurement method, ADCP current meter is more advanced and convenient to use as a measuring tool. Compared with the traditional method, it can provide more accurate and real-time ocean current data, which would be highly conducive to the operation and development of Xiamen Port.

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

The Acoustic Doppler Current Profiler(ADCP) is based on the principle of the Doppler effect. First, there are acoustic signals generated within the water. When such acoustic signals fall on moving particles in the water-sediment particles or small organisms carried by the ocean current, for example-the frequency of the reflected signals would shift. This frequency shift has a direct relation to the velocity of the moving particles and thus reflects the velocity of the ocean current.

It can receive the velocity profile in the ocean current by measuring the Doppler shift of the reflected acoustic signals at different angles and with various depths. Thus, it is able to measure both the horizontal and vertical components of the current velocity within a range of water depths.

In Xiamen Port, there are mainly two types of ADCP current profiler application: one is on shipborne. When a ship equipped with an ADCP meter is sailing in the port area, the ADCP is able to measure continuously the ocean current data along the route that the ship has gone through. By using this method, relatively large areas of the port waters can be covered and comprehensive current information obtained.

The other is fixed ADCP doppler. Fixed ADCPs are installed at some places in the port, like on the seabed near the berth or in the key channels. These fixed-position ADCP profiler flow meter is able to monitor the ocean current condition at these fixed positions continuously, which will provide the long-term and stable current data for operation in the port.

4. What is needed to realize high-quality measurement of the currents around Xiamen port?

If doing high-quality measurement for ocean currents in Xiamen Port, several factors concerning equipment are required. First is the material reliability of the equipment. The equipment should be small in size and light in weight. When an ADCP is small in size and lightweight, its installation and operation are easier, whether on a ship or at a fixed position. This also reduces the impact on the installation environment.

The other essential requirement is low power consumption. This will allow the ADCP to function for long periods without frequent replacement of the batteries or any problems with the power supply, particularly for fixed-position acoustic doppler flow meter which need to operate continuously. The cost should also be as low as possible. With cheap equipment, large numbers can be deployed in the port area for extensive current measurement coverage.

Considering the ADCP casing, titanium alloy is one of the best choices. First, titanium alloy has many striking advantages: high strength, excellent corrosion resistance. In such a seawater and marine environment, Xiamen Port, where most regular materials face severe corrosion, titanium alloy will keep acoustic doppler velocity meter stable and long-lasting. It can withstand the critical chemical conditions of seawater and the mechanical impact of sea currents. Another crucial advantage of the titanium alloy is that its density is comparatively low, which reduces the general weight of the ADCP without weakening it.

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

The choice of equipment for measuring currents should depend on a specific purpose of its use. In various application conditions, different types of ADCP will be used. The frequency is one of the major factors in choosing ADCP. Different frequencies suit different water depths. For example, for water depths within 70m, 600kHz ADCP is often a better choice. It is able to offer relatively accurate current measurement data in this comparatively shallow water area. When the depth is up to 110m, it becomes more suitable to use 300kHz. It does best in deeper water conditions within this range. For very deep water areas, say 1000m depth, the best would be 75kHz ADCP since it can penetrate well in deep water and measure the ocean currents.

Some known ADCP brands in the market are teledyne rdi, Nortek, and sontek. However, there is also an outstanding Chinese ADCP brand - China Sonar PandaADCP. It is made of all - titanium alloy material, which combines high quality with an incredible cost - performance ratio. You can learn more about this brand on its official website: https://china-sonar.com/. 

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