System overview
As science and technology continue to grow in our country, the importance of hydrology is becoming more prominent, especially in urban construction, and the availability of data from hydrological flow testing can be said to be crucial to efforts such as water resources use-level protection。
Traditional, practical river flow measurement methods are mainly current area methods, including current speed gauges, buoys, etc. Test methods include manual ship surveys, bridge surveys, cable measurements and water-related measurements. This traditional method of measurement is simple, practical and time-consuming and inefficient. As a result, the traditional current speed gauge method no longer meets the flow measurement needs of the information time, and the use of the adcp for river survey is a new method of flow testing developed and applied for more than a decade。
Drifting adcp features high accuracy, short test time, high resolution, good information and high amount of information, and meets the need for hydrometric measurements, which are larger in width and are heavily influenced by multiple factors, such as sediment. It can be said that the introduction and application of cruise-based dacp will be significant for the modernization and informatization of hydrology and will be a trend towards the modernization of the entire hydrosystem。
Flow measurement principles
Based on the doppler effect principle, the adcp ultrasound current system sends four fixed-frequency acoustic short pulses into the water, which will be dispersed when they touch the dispersors in the water (e. G. Plankton, sediment, etc.), and the echo signals received by the dacc from each beam can yield a fraction of the current's east, north and proximate speed. The entire water column from top to bottom is divided into several depth units, and the flow rate data of the depth units form the flow rate break. In the same data group, acp records bottom tracking speeds and breakwater velocity information, respectively, and the current velocity and current velocity can be analysed with current measurement software to map the distribution of the entire fault and then calculate the flow of the entire fault. Information can be shown on a real-time basis on the operational tracks of the dacc, underwater fault maps, etc。
System characteristics
Dynamic measurements: the traditional test methods, whether artificial vessel surveys, bridge surveys or water-related measurements, are those where measurement instruments are fixed and retrofitted, whereas measurements using the adcp instrument are carried out in a dynamic manner, and dynamic measurements are carried out in parallel with the cruise process。
High resolution: compared to the traditional flow gauges, the nap instrument resolution, speed accuracy and continuous measurement are significantly improved。
Quick measurement: when the dynasty of the dynasty is completed, the flow value of the dome can be directly measured without manual calculations, significantly reducing labour intensity and saving human and material resources。
High measurement accuracy: the traditional current speed gauge method can only place several points on a fault and requires manual calculation of flow values, while the navigating adcp method of current measurement is equivalent to a more dense spot on the retraverse, with higher natural accuracy of traffic data obtained due to higher collection rates。
Flexibility: in traditional testing methods, current faults are usually measured vertically on river banks. At the time of the survey, the results were not linked to the ship's route between the river and the other side, either in an oscillation or in a curve, thus further simplifying the measurement。
Easier to maintain: a cruise-based adcp measurement vessel is easier to maintain than a traditional flow-rate device and has a low failure rate and good reliability。
