2/17/2024 0 Comments Sound Particles Density freeThe change in the flow field due to particles has been investigated using particle-resolved simulations. 37,38 Although particle-laden flow is modeled based on knowledge of an isolated particle, the effect of complex flow and particle motion generated by aerodynamic interference between particles becomes important as the number density of particles increases. Similar experiments were conducted with particles placed on a shock tube floor, 35,36 with free-falling particles. ![]() This kind of experiment cannot capture instantaneous drag but can obtain the short-time-averaged drag coefficient. 34 visualized the interaction of suspended particles by a spider web with a planar shock, and the drag coefficient was estimated by analyzing the trajectories of the particles. This phenomenon becomes more apparent as the Reynolds number increases, and the drag may become instantaneously negative. In addition, the convergence of the Mach stem at the rear stagnation point of the particle was shown to provide instantaneous drag reduction. They found that the unsteady drag coefficient is several times higher than the steady drag coefficient. 33 investigated unsteady drag both experimentally and numerically. Particles in a high-speed flow experience interaction with shock waves. The wide distance between the two particles attenuates these pressure waves, and the particles reduce their motion away from each other. The pressure waves resulting from Mach stem convergence of the upstream particle and the reflected shock waves from the downstream particle are the main factors responsible for the force in the direction that pushes the particles apart. On the other hand, two particles placed in a side-by-side arrangement are only slightly closer to each other after the shock wave passes between them. Two particles placed in an in-line arrangement approach each other very closely due to the passage of a shock wave. These two particles become closer after the shock wave passes than in the initial state under most conditions. The time evolution of the unsteady drag and lift is changed by interference by the planar shock wave, Mach stem convergence, and the shock wave reflected from the other particle. ![]() The unsteady drag, unsteady lift, and particle behavior are investigated for different densities and particle configurations. The particle motion analysis is carried out based on particle-resolved simulations for one or two particles under a shock Mach number of 1.22 and a particle Reynolds number of 49, and the particle migration and fluid forces are investigated. Unsteady drag, unsteady lift, and movement of one or two moving particles caused by the passage of a planar shock wave are investigated using particle-resolved simulations of viscous flows.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |