Design Of Self-contained Turbulence Instrument

With the deepening of marine research, ocean turbulence has gradually become a hotspot of physical oceanography. The momentum, heat and mass transport of ocean water are closely related to ocean turbulence, which is also the energy source of regulation of ocean temperature and salinity circulation Besides, climate change also has close relation with it. At the same time, turbulence has an important influence on suspended material and the distribution of the marine environment. Research on ocean turbulence plays a key role in understanding the dynamic mechanism of ocean circulation and improvement of ocean circulation and climate models. Mean while, marine disasters and abnormal marine phenomena require a more accurate, detailed and deep understanding of marine micro structure movement—turbulence, so as to improve the existing marine disaster forecasting model. For this reason, ocean turbulence research has become an important area of marine scientific research, and the data acquisition technology of ocean turbulence has become the core of research of the marine observation technology.First, this paper summarize the history and status of the turbulence measurement, presents the history of the turbulent sensor and the development history and current situation of observation platform, and introduces the principle and application of the turbulence measurement by the shear flow sensor. Second, based on the principle of Moored Instrument, an observation platform which suits Moored Instrument is designed, the electrical design of the overall scheme is given.The turbulence instrument samples signals of turbulence as well as signals of acceleration and attitude, which are stored in the SD card in the form of documents. The signals of turbulence obtained by the shear flow sensors and amplified by the Charge Amplifier, are then converted to a digital signal by the 24-bit AD. Acceleration signals are composed of three analog signals which are obtained by three mutually perpendicular accelerometers, by which the acceleration signals are converted into digital signals by the 24-bit AD as the shear flow sensors. Attitude signals include measurement platform's heading angle, roll angle and pitch angle. Attitude signals measured by the TCM2.5 are sent directly to the serial port in digital form, which are stored in the SD card in the form of documents directly. There are strict requirements for the stability and attitude of observation platform. Observation platform's vibration signal (obtained by the acceleration) and the attitude signal has important applications in the final data processing.Since this instrument is used in Moored Instrument, this article also design a subsurface buoy system which is designed for the turbulence instrument's experiments in the offshore, and the system includes buoyancy unit, turbulence instrument, current meter, the connection unit, and anchor. Besides, the experimental data were analyzed, showing that the turbulence instrument measured accurately and reliably.