Structural Design And Numerical Simulation Analysis Of3-D Ocean Current Sensors

With the deepening of marine science research, high requests are put forward for current sensor used to measure marine flow velocity, which should measure not only horizontal velocity but also tiny upwelling velocity, thus three-dimensional current sensor that can measure tiny upwelling velocity is getting increasingly important. In order to solve the difficulty of precisely measuring of flow velocity that has large dimensional difference, this article studies upwelling measurable three-dimensional instantaneous current sensor under the grant of "upwelling measurable three-dimensional transient current sensor research" supported by National Natural Science Foundation of China.This article went through the overall scheme design of the upwelling measurable three-dimensional current sensor firstly, putted forward a scheme that measures flow velocity with large dimensional difference respectively, then designed horizontal velocity measuring device with cross elastic beam and upwelling measuring equipment with amplification mechanism. Following, the mechanical model between drag on the sphere and strain of the sphere was established on the basis of theoretical calculation of horizontal flow measuring device. Subsequently, I built a finite element model and made static analysis with Workbench, to analyze changes of deformation, strain and stress. Single factor optimization was carried out on the primary structure parameters to analyze its effect on device strain, further optimization was achieved through orthogonal experiment.Dynamic analysis was implemented on the device, its former sixth-order natural frequencies and model shapes were analyzed, and compared with flow field. Finally, I made fluid-structure coupling analysis on the optimized device, and got a set of data about flow velocity and device strain relationship, then fit the data with MATLAB, and achieved a function formula and trialled prototype sensor. Results showed that the designed three-dimensional velocity sensor realize simultaneous measurement of three-dimensional velocity, horizontal flow measuring device can measure flow velocity ranging from18mm/s to1320mm/s, thus fulfills the measurement of low flow velocity, and with simple structure. It can be widely used to various occasions of velocity measurement.