title: Modeling and simulation of Fluid-based gyroscope (Particle Imaging Velocimetry Gyroscope)
Creators: name: Elaswad, Ramy
Publisher: name: Graduate Studies
Year: 2024
Subjects: subject: Engineering--Mechanical

description: A gyroscope is a device used for measuring or maintaining orientation and angular velocity. Gyroscopes, as rotation sensors, are part of inertial navigation systems (INS), which also include motion sensors (accelerometers). As inertial sensors' accuracy has developed over time, they are now sufficient for navigation and guidance applications in terms of size, weight, cost, and accuracy. Among the most important classes of inertial navigation sensors are fluid-based devices. These have the advantages of simple structures, low cost, high shock resistance, and long measurement ranges. However, sensitivity and bandwidth cannot be compared. Particle Imaging Velocimetry Gyroscope (PIVG) is a fluid-based sensor that was first introduced in 2020. The PIVG sensor shall have a conceptual design based on the particle imaging velocimetry technique, which is an experimental tool of fluid dynamics science. Modeling and simulation play a significant role in identifying the conceptual design and the technology which shall be used in the creation of a new sensor. In this research we intend to develop and optimize the PIVG sensor design parameters. The aim, hence, is to reach a mathematical model with a wide input range domain to ensure an appropriate dynamic range for the operation of the sensor. Afterwards, it is necessary to simulate the derived model in order to optimize the design of the PIVG sensor. In this regard, Computational Fluid Dynamics (CFD) simulations are held due to the fluid-based nature of the sensor. The study focuses on fluid-particle dynamics in an accelerated toroidal flow channel with attention to PIVG technology. Detailed grid convergence studies and validation against experimental data establish the accuracy and reliability of our developed computational models. We conducted an analysis for a range of Dean numbers from 10 to 70, considering the primary and secondary flow patterns, pressure distribution, and their interrelation within the structure. It determines the Dean number value that gives stable fluid dynamics to be De = 11, corresponding to a toroidal geometry where the curvature radius is 25 mm, and the diameter of the cross-section is 5 mm. Besides, it evaluates how solid particles of sizes 10, 50, and 100 microns behave in this toroidal flow. Results indicate that the behavior is critically dependent on the size of the particles; small ones follow very well with fluid flow, while larger ones indicate a noticeable lag due to inertial forces. Also, this research simulates particle behavior under different angular accelerations of 4 rad/s², 6 rad/s², and 8 rad/s² for 1100 kg/m³, 1050 kg/m³, and 980 kg/m³ applying CFD. The particle concentration distribution, velocity profiles, and displacement patterns were examined for a volume fraction of 1.5% and particle size of 50 microns in a toroidal geometry. The outcome showed that the density of the particles had an effect on the behavior/displacement: for heavier ones, settling started faster, while lighter ones remained relatively distributed homogeneously. These findings are important in the optimization of PIVG sensor design and accuracy. As well as the present study proposes a very promising pathway for the role of CFD in understanding and improving fluid and particle dynamics within toroidal structures for future research and applications in navigation systems.