The Design and Performance Study of Magnetic Liquid Acceleration Sensor

This paper focuses on the design and performance of magnetic fluid acceleration sensors, systematically sorting out their theoretical basis, structural design, magnetization characteristics and dynamic response mechanism. Magnetic fluid, as a new type of functional material with both ferromagnetism and fluidity, has broad application prospects in inertial sensors due to its unique field control behavior. The article first reviews the development history of magnetohydrodynamic sensors at home and abroad, covering various sensing forms such as micro-pressure difference, tilt Angle and acceleration, and points out that its modular design provides a technical path for multi-dimensional performance optimization. In terms of theoretical modeling, the article establishes a second-order inertial system model of the magnetohydrodynamic acceleration sensor, clarifies the action mechanisms of magnetic buoyancy and magnetic viscosity in restoring force and damping, and realizes the conversion of acceleration to electrical signal based on inductance and Hall elements respectively. Magnetic property analysis indicates that the magnetic fluid exhibits superparamagnetism, and its saturation magnetization intensity (coal-based > oil-based > water-based) is directly related to the sensor's sensitivity and dynamic range. The rationality of the magnetic circuit design was verified through COMSOL finite element simulation, revealing the key influence of magnetic gradient on displacement detection. The dynamic performance test results show that the coal-based magnetohydrodynamic sensor has the optimal transient response (rise time 0.122 s, stabilization time 0.323 s, overshoot 11.4%) and maximum bandwidth (25.37 rad/s), indicating that it is suitable for high-frequency vibration scenarios.