The wavepacket is a model that bears close resemblance to naturally-occurring laminar turbulent transition processes in a boundary layer, but its large number of constituent spectral modes presents a challenge during analysis of the results. In this work, we leverage the extensive flow data available from direct numerical simulations (DNS) to perform a three-dimensional (3D) discrete Fourier transform of a wavepacket in order to investigate the most energetic modes in the flow. Through windowing, it is possible to isolate the wavepacket at different stages of its development, and build up an overall picture of its transition. Furthermore, an inverse transform is applied to subsets of the full spectrum, and this provides insight into the physical structure of its key components.
|Title of host publication||Advances in computation, modeling and control of transitional and turbulent flows|
|Editors||Tapan Sengupta, Sanjiva Lele, Katepalli Sreenivasan, Peter Davidson|
|Publisher||World Scientific Publishing Co. Pte Ltd|
|Number of pages||9|
|Publication status||Published - Jan 2016|
Kang, K. L., & Yeo, K. S. (2016). Forward and inverse 3D Fourier transforms of a DNS wavepacket evolving in a Blasius boundary layer. In T. Sengupta, S. Lele, K. Sreenivasan, & P. Davidson (Eds.), Advances in computation, modeling and control of transitional and turbulent flows (pp. 416-424). World Scientific Publishing Co. Pte Ltd. https://doi.org/10.1142/9789814635165_0041