Analysis of flow field and Pressure fluctuation for a falling disk

Abstract

The vortex structure pressure fluctuation and three kinds of behavior of motion for a free falling disk are simulated in this study The three kinds of behaviors of motion are fluttering tumbling and spiral There are three dimensionless parameters are chosen to produce the kinds of behavior of motion which are dimensionless moment of inertia I^* Archimedes Number Ar and Reynolds Number Re will determine the behavior of motion in this study For each case we analysis the periodicities about the disk’s motions the forces acted on the disk and the pressure fluctuation monitored at some points in the middle field By analyzing the FFT spectrogram the results show that vertical disk motion has same period as the pressure fluctuation We also found that the vortex dominates the pressure distribution in the flow field as well as on the disk

Date of Award	2019
Original language	English
Supervisor	San-Yih Lin (Supervisor)