A construction method and application of a large-scale reservoir sounding reference field

Abstract

The invention provides a construction method and application of a large-scale reservoir sounding reference field. The location of the reference field: in order to meet the calibration technical requirements of various sounding equipment, it is necessary to lay out various forms of reference points and reference surfaces; reference point construction; reference surface construction. Based on the sounding reference point, it is possible to conduct research on sounding error, positioning error, and water level correction error, including the nominal accuracy of the sounding instrument, sounding method, actual depth of sounding, and the influence of dynamic draft; positioning accuracy, GNSS data update rate, and differential method Influence, etc.; water level reckoning model, etc. Based on the sounding datum, it is possible to conduct research on the sounding environment error and GNSS three-dimensional channel sounding accuracy, including wave effects, positioning center deviation effects, single-beam sounding attitude effects, sounding delay effects, ship speed effects, beam angle effects, Coupling effect, water body characteristics, bathymetry sampling frequency and smoothing method, sound ray tracking, and multi-beam bathymetry system bathymetry point cloud precision analysis and other impact studies.

Description

technical field [0001] The invention belongs to the technical field of reservoir sounding, and in particular relates to a construction method and application of a large-scale reservoir sounding reference field. Background technique [0002] Problems facing the current sounding: [0003] (1) After the reservoir is impounded, the impact of the sounding environment on the sounding accuracy tends to be complicated. [0004] The average working water depth of inland water depth measurement in my country is generally less than 50m, and large water depth measurement is generally more common in ocean measurement. Due to the different operating environments (water depth, water temperature, flow field, wave, salinity), the accuracy requirements are different, and the observation methods and indicators followed are not suitable for inland water bodies. After the impoundment of important reservoirs in the Three Gorges and its upper reaches, the water depth doubles. For example, after ...

AI Technical Summary

Problems solved by technology

It will cause the change of sound velocity and cause the refraction of sound rays, which will seriously affect the sounding accuracy of canyon reservoirs

[0005] (2) After the reservoir is impounded, the sounding accuracy of the conventional depth sounder is limited under the condition of large water depth

[0006] With the completion and operation of the Three Gorges and important reservoirs in the upper reaches, the water depth has increased significantly compared with that before the impoundment. The speed of the ship is measured, and the speed of the topographic observation ship in the Three Gorges reservoir area has been reduced to 4kn (2m / s). At the same time, in order to ensure the stability of the results, a section needs to be continuously observed twice, and finally the data with better accuracy is obtained, which seriously limits the operation. efficiency

At the same time, due to a series of problems such as the inability to completely eliminate the influence of the surveying ship attitude, the difficulty in synchronizing the time of the sounding and positioning signals, and the difficulty in correcting the beam angle effect, etc., especially the inclination angle of the nearshore slope is mostly between 0° and 30°, and the inclination angle of some reservoir sections is still low. It exceeds 30°, and the slope of special parts even reaches 90°, and the beam angle effect is further amplified. Therefore, the current large water depth observation accuracy has been maintained within 1% of the relative water depth, and it is difficult to make a breakthrough

[0007] (3) There is a lack of benchmarks for high-precision sounding technology research under large water depth conditions

[0008] The biggest problem in the study of underwater terrain observation accuracy is that the underwater terrain is constantly changing under the action of water flow, and it cannot have a stable true value like the shore topographic observation, which can be used as a benchmark for bathymetry research

Therefore, the current "Water Channel Observation Standards" (SL257-2017) uses repeated observations to evaluate the accuracy of underwater bathymetry, and analyzes and counts the difference between repeated observations. Due to the lack of high-precision and stable underwater reference points (this bottom terrain), so it belongs to the concept of relative accuracy, it is difficult to observe and count the absolute accuracy, and further analyze the factors affecting the sounding accuracy, creating obstacles for targeted research

Images