Study On The Gas Solubility And Performance Of Conductive Fluid In MHD Micro-angle Vibration Sensor

The MHD(magnetohydrodynamic)micro-angle vibration sensor based on magnetohydrodynamics is sensitive to micro-vibration frequency and angular rate,and has high dynamic characteristics and wide damping adjustment characteristics.Compared with traditional angular velocity sensors(such as gyroscopes),there is no mechanical wear and friction damping,high reliability and long life,and they are widely used in the aerospace field.At present,the research of MHD micro-angle vibration sensor mainly focuses on the fluid ring structure,magnetic circuit structure,low frequency expansion and signal noise reduction,etc.There are few reports on the internal conductive fluid parameters and the impact on the performance of the sensor,such as the gas solubility of conductive fluid with temperature The influence of the change on the sensor,the influence of the expansion coefficient of the conductive fluid with the temperature on the sensor,etc.Affected by temperature,the conductive fluid expands or contracts,the gas is immersed or released,or the gas is introduced during assembly to form a gas-liquid two-phase flow,which affects the flow rate and output potential of the conductive fluid,which in turn affects the accuracy of the sensor.In this paper,for the conductive fluid materials used in the current MHD microangle vibration sensor,the following studies have been made from the gas solubility parameters and the impact on the sensor performance:First,the working principle of the MHD micro-angle vibration sensor is explained,and the influence of the two-phase flow formed by gas and conductive fluid on the output accuracy of the sensor is analyzed.Using the CFD simulation software,the flow field magnetic field of the fluid ring inside the sensor is coupled and simulated.The relationship between the single-phase flow of the conductive fluid,the gas-liquid twophase flow of the conductive fluid,the distribution characteristics of the output potential and the gas content is theoretically analyzed.It shows that the influence of gas content on sensor performance is different.Secondly,study the gas solubility of the conductive fluid,that is,in an ideal state,whether the gas immersed in the conductive fluid affects the sensor.The investigation and analysis of the existing solubility determination method,on this basis,innovatively proposed a combination of static method and dual volume pressure decay determination method(patent has been declared)and formulated an experimental program.Designed and built an experimental device,using Python language and Qt library to write the host computer data acquisition and processing software,the system joint debugging is stable and reliable.Finally,using the designed experimental device according to the experimental scheme,the experiment of measuring the gas solubility of the conductive fluid was completed.Experiments show that the gas solubility of conductive fluids decreases nonlinearly with increasing temperature in the normal pressure range.Combined with theoretical simulations,it is concluded that the effect of the gas solubility of the conductive fluid measured under the experimental conditions on the sensor output potential is less than 0.03%.It lays a theoretical foundation for the design of subsequent sensors.