2022/10/18 by Narinder Singh, Singh, Narinder, Anikesh Pal +1
Computer Science · Economics, Econometrics and Finance · Engineering · #Complex Systems and Time Series Analysis #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Fluid Dynamics and Turbulent Flows #Nonlinear Dynamics and Pattern Formation
paper · pdf · doi:10.48550/arxiv.2210.09584
openalex publication_date 2022/10/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The effect of the rotation on the turbulent mixing of two miscible fluids of small contrasting density, produced by Faraday instability, is investigated using direct numerical simulations (DNS). We demonstrate that at lower forcing amplitudes, the t.k.e. increases with an increase in f till (f/ω)2<0.25, where ωis the forcing frequency, during the sub-harmonic instability phase. The increase in t.k.e. increases BV, which increases the total potential energy (TPE). A portion of TPE is the APE. Some parts of APE can convert to t.k.e. via BV, whereas the rest converts to internal energy, increasing BPE through ϕi. The remaining TPE also converts to BPE through the diapycnal flux ϕd resulting in irreversible mixing. With the saturation of the instability, irreversible mixing ceases. When (f/ω)2 > 0.25, the Coriolis force significantly delays the onset of the sub-harmonic instabilities. During this period, the initial concentration profile diffuses to increase TPE, which eventually expends in BPE. The strong rotational effects suppress t.k.e.. Therefore, BV and APE become small, and the bulk of the TPE expends to BPE. Since the instability never saturates for (f/ω)2 > 0.25, the BV remains non-zero, resulting in a continuous increase in TPE. Conversion of TPE to BPE via ϕd continues, and we find prolonged irreversible mixing. At higher forcing amplitudes, the stabilizing effect of rotation is negligible, and the turbulence is less intense and short-lived. Therefore, the irreversible mixing phenomenon also ends quickly for (f/ω)2<0.25. However, when (f/ω)2>0.25 a continuous mixing is observed. We find that the turbulent mixing is efficient at lower forcing amplitudes and rotation rates of (f/ω)2 > 0.25.