Improvement and application of control-volume model on honeycomb seal

As for the analysis of honeycomb seal rotordynamics, the two-control-volume model is an efficient approach that is applied well. This paper starts with six relative governing equations, which are resolved into three dimensionless equations after a nondimensionalized process. It contains a zeroth-order equation, through which a steady fluid distribution is determined and a judgment is made whether the choked flow exists, and a first-order equation, through which the seal's rotordynamic coefficients can be acquired. In this paper, Blasius frication model is used for the surface of both stator and rotor due to its briefness and effectiveness. Furthermore the original assumption that the shaft moves in an orbicular track is discarded and this paper assume that the shaft moves in an elliptical track. And since the model is formulated with matrix form, the relevant operation becomes very simple so that the approach in this paper has a clearer model and a more concise algorithm than the previous ones. At last a comparison between the theoretical and experimental results are made to demonstrate the effectiveness of the model and the algorithm as well as a contrast between honeycomb seal and general annular gas seal to explain the advantage of honeycomb seal in stability. Also a series of investigations about the influence of some seal parameters reveal some helpful and practical rules.