If the cavity is completely filled it will become fluid within the rotating parts.
What does thixotropic mean in terms of viscosity?
Definition - What does Thixotropic mean? A thixotropic fluid is one that takes a fixed time to return to its equilibrium viscosity when subjected to abrupt changes in shear rate. In other words, the liquid becomes less viscous (thinner or flows more easily) when shaken, stirred, agitated or otherwise stressed.
What is Thixotropic? - Definition from Corrosionpedia
www.corrosionpedia.com/definition/2400/thixotropic