The Influence of Structural Parameters on the Stability of Blade-Casing Interactions in Turbomachinery

Blade-casing interactions are common in modern turbomachinery. They occur due to small tip clearances between the blades and the casing, which are designed to be minimal for efficiency reasons. Rubbing between the two components may cause severe vibrations, ultimately resulting in structural failure. Recently an analogy between this problem and the machine tool chatter has been proposed. It results in a representation where the dynamics are governed by linear time invariant delay-differential equations. The stability analysis of such systems is complex and clearly of critical importance. Stability characteristics are causally related to the system parameters. Following some earlier results, the present article reveals the relation between these parameters and the stability characteristics of the system. The results are demonstrated on a case study.