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The flow in the rim seal of a one-stage axial turbine with 30 stator and 62 rotor blades is analysed by large-eddy simulation (LES).The Navier-Stokes equations,are solved by a parallelized finite-volume solver based on a Cartesian immersed boundary/level-set approach.The rigid surfaces are tracked by a level set method and a sharply resolving and strictly conservative cut-cell formulation is used for the wall boundaries.Two adaptive Cartesian meshes are used,the first to track the embedded surface boundaries with the level set and the second to discretize the fluid domain for the numerical solution of the conservation equations.The overall numerical method allows highly resolved simulations of turbomachinery applications with multiple surfaces moving relative to each other in a single frame of reference.All stator and rotor blades are resolved,i.e.,the domain comprises 360° in the cirumferential direction.The analysis of the simulation results focuses on the flow inside the cavity between the stator and the rotor disks of the turbine stage with a single lip rim seal configuration.A mesh resolution study is conducted first,before the LES results are compared to experimental data.Finally,a detailed analysis of the flow field inside the rotor-stator wheel space is conducted.A dominant mode of the radial velocity component is identified,which is unrelated to the rotor frequency and its harmonics.It is shown that this mode has a major impact on the ingress of the hot gas into the rotor-stator wheel space.baseline skip:12.51291pt