Saved in:
| Main Authors: | , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2408.15944 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866929478051037184 |
|---|---|
| author | Cui, Guangyao Jacobi, Ian |
| author_facet | Cui, Guangyao Jacobi, Ian |
| contents | The amplitude modulation coefficient, $R$, that is widely used to characterize non-linear interactions between large- and small-scale motions in wall-bounded turbulence is not actually compatible with detecting the convective non-linearity of the Navier-Stokes equations. Through a spectral decomposition of $R$ and a simplified model of triadic convective interactions, we show that $R$ actually suppresses the signature of convective scale interactions, and we suggest that what $R$ likely measures is linear interactions between large-scale motions and the background mean flow. We propose an alternative coefficient which is specifically designed for the detection of convective non-linearities, and we show how this new coefficient, $R_T$, also quantifies the turbulent kinetic energy transport involved in turbulent scale interactions. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2408_15944 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | The interpretation of the amplitude modulation coefficient and a transport-based alternative Cui, Guangyao Jacobi, Ian Fluid Dynamics The amplitude modulation coefficient, $R$, that is widely used to characterize non-linear interactions between large- and small-scale motions in wall-bounded turbulence is not actually compatible with detecting the convective non-linearity of the Navier-Stokes equations. Through a spectral decomposition of $R$ and a simplified model of triadic convective interactions, we show that $R$ actually suppresses the signature of convective scale interactions, and we suggest that what $R$ likely measures is linear interactions between large-scale motions and the background mean flow. We propose an alternative coefficient which is specifically designed for the detection of convective non-linearities, and we show how this new coefficient, $R_T$, also quantifies the turbulent kinetic energy transport involved in turbulent scale interactions. |
| title | The interpretation of the amplitude modulation coefficient and a transport-based alternative |
| topic | Fluid Dynamics |
| url | https://arxiv.org/abs/2408.15944 |