Investigation Of Self-active Sensor Based On Triboelectric Nanogenerator For Ship Draught Detecting

As one of the most important factors that reflect the safety of navigation,the ship's draught is of great is quite important to prevent ship from overturning and ensure ship's stability and safety.Currently,the ship's draught monitoring system is lack of precision with complex system and higher cost.Triboelectric nanogenerator(TENG)has great potential application in a self-active real-time water level monitoring system,due to its superiority of high-precision,lightweight and self-active.The present paper designs and investigates a distributed-electrode tubular triboelectric water level sensor(DET-TWLS)based on the principle of freestanding TENG driven by sliding electrification and electrostatic induction.The main research contents and conclusions are as follows:Firstly,the present paper studied the working mechanism of the solid-liquid tubular TENG(T-TENG)to establish the V-Q-x relationship equation.The relationship between the water level and the output voltage(Voc)induced by solid-liquid contact electrification is investigated.The distribution of potential is simulated by finite element method.Secondly,the T-TENG and DET-TWLS are fabricated.Their inner surface microstructure ablated by laser technique to increase the surface charge density and hydrophobicity.Copper electrodes are coated on their out surface of the tube by evaporative sputter coating technique.Then,the influence of electrode width and distribution,tube diameter,flow velocity and ion concentration on the output performance are studied systematically based on the control variable experiment method.It is found that the induced voltage varies in the same way with the amount of transferred charge.Both of them are proportional to the width of the electrode and the diameter of the tube.Their peaks reach 70V and 40nC,respectively.But the short current is mainly related to the flow velocity and more irregular than the variation of the voltage.In addition,the open voltage is found to decease with the increment of the salinity of working fluid.Thirdly,two types of DET-TWLS with and without saccule are designed and applied to measure the water level.The DET-TWLS is found to be much accurate and stable to monitor the water level with the resolution being 1cm and the error rate being 0.5%after 20 times test.The encapsulated DET-TWLS is applied to measure ship draught in the lab condition and shows excellent performance.