MSD-based transient fluid model of liquid circular angular accelerometer for vibration-induced error analysis

This paper investigates the errors induced by linear vibration in the fluidic system of liquid circular angular accelerometers (LCAAs). A two-dimensional mass-spring-damper model is proposed to analyze the pressure difference between both sides of LCAA transducer subjected to linear vibration in both transient and steady states, where the compressibility of fluid is taken into account. The complex flow patterns of fluid are simplified to the positional changes of fluid particles. Springs and dampers are utilized to simulate the forces inside the fluid and between the fluid and the tube wall. Simulations are carried out based on the linear acceleration step excitation to explore the influence of model parameters, LCAA structure parameters and fluid parameters. The proposed model is validated by comparing the characteristics of the simulated pressure difference with their corresponding theoretical values, and is further verified by the comparison with the results from computational fluid dynamics method. Furthermore, the pressure difference under linear acceleration excitations in various forms is analyzed. The results indicate that the abrupt changes in linear acceleration are the primary cause of pressure difference oscillation, and the compressibility of fluid leads to increased pressure difference.