2025/02/02 by Ming Yuan, Zhiye Zhao, Yuan, Ming +8
Engineering · #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Particle Dynamics in Fluid Flows
paper · pdf · doi:10.48550/arxiv.2502.00625
openalex publication_date 2025/02/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Nonlinear evolutions of two-dimensional single-mode compressible Rayleigh--Taylor instability (RTI) with isothermal stratification are investigated in cylindrical geometry via direct numerical simulation for different Atwood numbers (AT=0.1-0.9) and Mach numbers (Ma=0.1-0.9). It is found that the nonlinear bubble growth involves the effects of density stratification, vorticity accumulation and flow compressibility and shows considerable differences between convergent (acceleration acting radially inward) and divergent (acceleration acting radially outward) cases. Specifically, the density stratification leads to non-acceleration at low AT and high Ma. The accelerations in convergent cases are dominated by vorticity accumulation at low AT and low Ma and by flow compressibility at high AT and high Ma whereas the accelerations in divergent cases are purely induced by flow compressibility at high AT and high Ma. Based on the nonlinear theory of incompressible cylindrical RTI with uniform-density background~(Zhao et al., J. Fluid Mech., vol. 900, 2020, A24), an improved model is proposed by taking the density variation, vorticity accumulation and flow compressibility into consideration. This model is verified by numerical results and well reproduces the bubble evolution for different AT and Ma from linear to highly nonlinear regimes.