By means of finite element method

the changes of the tip clearance of an aeroengine's high pressure turbine(HPT) were calculated

the influences of pressure

temperature and rotation speed were considered and a new method of applying the boundary conditions was presented as well.After comparison with and analysis of former methods

this paper has reached some reasonable conclusions: the shaft speed plays a major role in the displacement of turbine disc

while the temperature is a major influential factor to the blade and shroud.Minimum tip clearance will occur during the first acceleration of the engine and the re-burst processes

respectively.