Research On Chip For Detecting Ship Machinery Oil Contaminants Based On Opposite Coil

As the blood of marine machinery,the ship engine oil can get the operation of marine machinery to diagnose faults and make early warning through the detection of pollutants in ship engine oil.The hydraulic oil is one kind of ship machinery oil,used in various hydraulic mechanical systems,and it is an important carrier of mechanical faults.Therefore the detection of pollutants in the hydraulic system can not only obtain the internal wear conditions,but also diagnose the system,so as to understand the current situation and possible faults of the hydraulic system.This paper designs a detection chip based on multi-signal oppose coils,and conducts differentiated detection experiments and chip optimization simulation.By studying the action mechanism of the opposite coil sensor on the separate detection of abrasive particles,water droplets and bubbles of different properties;the mechanism of the signal change of the multi-parameter sensor caused by different external parameters.Using the finite element analysis software COMSOL Multiphysics,a multi-parameter sensor model was established,the relationship between the particle size of the pollutants with different properties and the detection signal,as well as the self-inductance,mutual inductance and flow channel shape of the opposed coils were studied.Build a testing experiment system,and test the oil samples containing different pollutants on the system.Experimental research on the number of coil turns,excitation frequency,traditional flow path and annular flow path,the best parameters of the detection chip and the optimal excitation signal are obtained,then each pollutant is tested separately to obtain the lower detection limit of metal particles,bubbles and moisture in the oil.At the same time,the distance between the two helical coils and the addition of silicon steel sheets in the helical coils are simulated and optimized to explore the impact on the inductance detection and capacitance detection.The annular flow channel in the new detection chip designed in this paper can achieve zero-distance contact of the detection substance,and the opposite coil structure sensor increases the electromagnetic field strength and improves the sensor detection capability.The detection chip can detect 30μm iron particles,1 10μm copper particles,100μm water droplets and 180μm bubbles,the detection signal has a high signal-to-noise ratio and the detection space is greatly improved.In the frequency range studied in this paper,when the excitation parameter of the inductance detection impedance analyzer is set to 2MHz,the detection signal is the best;when the excitation parameter of the capacitance detection impedance analyzer is set to 1.3MHz,the detection signal is the best.As the number of turns of the inductor coil increases,the amount of change in inductance becomes larger,and the rate of change in inductance decreases.The amount of change in the inductance and capacitance detection signals decreases as the coil spacing increases.The silicon steel sheet increases the inductance detection energy.The opposite coil detection chip can realize the detection and counting of multiple substances;the opposite coil structure improves the detection sensitivity;the design of the annular flow channel increases the detection flux and improves the detection efficiency.