Numerical Computational And Experimental Study On The Dynamic Coefficient And Damping Performance Of Honeycomb-Seal

This paper used computational fluid dynamics (CFD) to calculatle the dynamic coefficient of the honeycomb-seal.The 3D models of a cylindrical honeycomb-seal and a conical honeycomb-seal were built.The geometry of the model and boundary conditions was according to Satoru Kaneko's experiment.Because the geometry of honeycomb-seal was complex and flow parameters were changing dramatically in the narrow gap of seal, the paper used hexahedral meshes, high-density meshes on the radial direction of the gap of seal;the moving coordinate system, the RNG turbulence model which was more suitable to near-wall flow and non-equilibrium wall functions was used to gain the dynamic coefficient of the two kind of honeycomb seal. Finally, the numerical computational result, analytic computational result and experimental data were compared. It proved that the numerical computational result was more similar to the experimental data.After the accuracy of the numerical computation was approved, this paper built different honeycomb seal model with different lattice depth, it showed that numerical computation was a good method for the analyse of the dynamic performance and the optimized design of honeycomb-seal in the future.On the other hand, this paper measured the vibration of shaft directly to experimentlly study the dynamic coefficient and damping performance of honeycomb seal. It showed that the smooth wall cause larger vibration for the unbalance of pressure in the seal gap when the rotor was eccentric. And the honeycomb wall did not cause significant changes in frequency, waveform, or amplitude when the the rotor was eccentric.Besides there was larger effective damping than smooth wall that can restrain the vibration caused by unbalance quality.