vibrations-at-seal-membraneTypicalcrack locationStatic seal carrierRing spacewith lowpressureHigherpress.Resilientwall of thering duct Intermittent leakage air flow at the spring-like sealing coverSpring-like seal membranes can be excited topowerful vibrations through the leakage airflow. Intermittent leakage air flow at the resilientsealing cover plateWhen the seal touches the disk, the pressure underneaththe membrane builds up until the seal lifts. This creates apressure drop in the escaping air flow at the seal gap,causing the seal gap to close, etc., etc.Compressed airElasticmembraneTypical crack locationscorresponding to a form-dependent 30° split.Crack lengths up to 150 mmExcitement principle of the depicted damage -"hydrodynamic paradox".