Flow past an inclined spheroid in homogeneous and stratified environments

TL;DR

This study uses large-eddy simulations to analyze how flow around an inclined spheroid varies with different Froude numbers in homogeneous and stratified environments, revealing asymmetries and flow characteristics.

Contribution

It provides detailed insights into flow behavior around an inclined spheroid at various Froude numbers, including asymmetry patterns and force coefficients, which were not previously characterized.

Findings

Flow asymmetry at high Froude numbers ($Fr = ext{infinity, 6}$).

Symmetric flow at lower Froude numbers ($Fr = 1, 1.9$).

Quantitative analysis of pressure, friction, and drag coefficients across Froude numbers.

Abstract

Large-eddy simulations (LES) are performed to study the flow past a 6:1 prolate spheroid placed at an angle of incidence of $\alpha = 10^{\circ}$. The diameter-based Reynolds number ($Re = U_{\infty}D/\nu$) is set to a value of $5\times10^{3}$ and four values of diameter-based Froude numbers ($Fr = U_\infty/ND$) are analyzed: $Fr = \infty, 6, 1.9,$ and $1$. Visualizations of coefficient of pressure ($C_p$) and friction ($C_f$) contours reveal asymmetry in the $Fr = \infty$ and $6$ flows while, at $Fr = 1$ and $Fr = 1.9$, the flow over body does not have any visible asymmetry. This finding is further corroborated through the analysis of force coefficients on the body. The changes in the pressure coefficients ($C_p$), friction coefficients ($C_f$), and drag coefficients ($C_d$) with the Froude number are described in detail for $\alpha = 10^{\circ}$. We also present the analyses of forces on the body at $\alpha = 0^{\circ}$ angle of incidence for comparison with the $\alpha = 10^{\circ}$ cases.