Large-eddy simulation (LES) of particle-laden, swirling flow in a coaxial-jet combustor is performed. A mixture of air and lightly loaded, spherical, glass-particles with a prescribed size-distribution enters the primary jet, while a swirling stream of air flows through the annulus. The incompressible, spatially filtered Navier–Stokes equations are solved on unstructured grids to compute the tu...

Soot concentration distribution is investigated both numerically and experimentally in methane-air diffusion flame. The experimental work is conducted with a cylindrical swirl stabilized combustor. Filter paper technique is used to measure soot volume fraction inside the combustor. The numerical simulation is based on the solution of the fully-coupled conservation equations for swirling turbule...

Bubbles and the dissolved gases in liquids greatly influence the performance of fluid power systems, coating solutions, plants in the food industry and so on. Therefore, it is important to eliminate bubbles in liquids and to prevent degradation of the quality the system performance as well as to avoid possible damage of the components. These problems are often viewed with the knowledge of the d...

A numerical investigation of the multiple stable solutions found in confined swirling flows is presented. The flows consist of fluid in a completely filled cylinder driven by the constant corotation of the two end walls. When reflectional symmetry at the cylinder half-plane is imposed, the flow corresponds to that in a cylinder of half the height driven by the bottom end wall, with the top surf...

We examine enclosed swirling transitional and turbulent flows in a cylindrical vessel, driven by a single rotating endwall. The cylinder height:radius ratio H/R = 1 was chosen explicitly to preclude the possibility of vortex breakdown on the cylinder axis, thus concentrating attention on the behaviour of the cylindrical sidewall boundary layers. Over a range of Reynolds numbers above Re = ΩR2/ν...

The steady flow of a Reiner-Rivlin fluid with Joule heating and viscous dissipation is studied. We present a novel technique for accelerating the convergence of the spectral-homotopy analysis method. Solutions of the nonlinear momentum and energy equations are obtained using the improved spectral homotopy analysis method. Solutions were also generated using the spectral-homotopy analysis method...

The POD makes possible to reduce the complete highdimensional acoustic field to a low-dimensional subspace where different modes are identified and let reconstruct in a simple way a high percentage of the variance of the field. Rotating modes are instabilities which are commonly observed in swirling flows. Such modes can appear under both cold and reacting conditions but that they have differen...