The Research And Development Of Turbulence Measurement Instrument Based On Underwater Glider

Oceanic turbulent mixing process has an important role in regulation ofthermohaline circulation. Therefore,quantifying the ocean turbulence and mixingintensity, generally represented by dissipation rate of turbulent kinematic energy(TKE), is essentially important, and it is usually fulfilled by insitumeasurement.Inorder to meet the urgent need of long-term continuous turbulent mixing oceanobservations,the paper developed the turbulence measuremeant instrument based onunderwater glider.Advantage of using a underwater glider mobile platform to measureocean turbulence is a high degree of autonomy, measurement process does not requirepersonnel to operate and unaffected by the ship time and sea conditions and long-terma wide range continuous observation.Paper mainly from three aspects introduced turbulence measurement instrument,respectively mechanical design, electronic system design and data denoisingalgorithm.And through laboratory tests and lake tests were conducted on thescientific validation of observation platform and instrument.First, turbulence measurement instrument design for mechanical parts mainlyinclude fairing design, pressure hull design and sensor installation location design.Thefairing is streamlined to reduce the glider resistance and protection of pressureshell.Pressure shell is mainly used to bear the pressure of water.According to theturbulence measurement principle for sensor installation location is reasonable design.Secondly,electronic system design mainly includes low noise analog signalconditioning module;multi channel data acquisition;large capacity data storagemodule and low power consumption management module.Low noise analog signalconditioning module will amplify the weak signal produced by the sensor and reducethe signal loss in the transmission of analog channels.Multi channel data acquisitionmodule function is high-speed A/D conversion of the analog signal and making use ofthe large-capacity storage module for storing the data.Low power consumptionmanagement module rational allocation of power to reduce power consumption foreach module to achieve the purpose of long-term observations.For the turbulent signals are vulnerable to the effects of observation platformvibration.Paper proposed the wiener filtering data denoising algorithm,which is basedon the optimal weighting factor of shear signal and the acceleration signal,to remove vibration signal noise for obtaining effective turbulence data.Finally, in order to verify the effectiveness and stability of the instrument, designof the pressure test, the reliability of electronic test and glider balancing test, and theQiandao Lake lake test, test results show that the turbulence instrument glider couldreach the turbulence measurement requirements and accuracy of denoising algorithm.