 Finite Element Analysis of Casing Stability and Radial Growth of a Steam Turbine Disc

Mr Veeresh P, Mr Harish, Mr Prashantha Kumar, Asst Prof
International Journal for Ignited Minds   unpublished
In the present work, disc assembly used for an industrial power generation turbine is used for finding the structural safety. Casings are provided on the turbine disc assembly to protect it from falling of dust particles and also to provide lubrication and other controls. The main objective of the present work is to check the radial deformation of the turbine disc for closing gap between the disc and the casing. Initially casing analysis has been carried out to check the stability and the disc
more » ... s analyzed for the radial deformation and structural stress condition. Also modal analysis has been carried out to find the structural dynamic stability. Further simplified geometries are built to find the effect of inclination of ribs on the stress and deformation generated under rotational load of 11000 rpm. The analysis has been carried out in the cyclic symmetry domain due to repetitive segments. Similarly analysis has been carried out with cutouts which are similar to the practical problems. The results for uncut geometry show lesser influence of inclination of ribs on the stress and deformation generation. But in case of cutouts it shows a certain influence on the deformation and stress generation. The rib inclination increases the stress and deformation in the problem along with reduction in the natural frequencies. So inclination is not a desirable feature with turbine discs. The same thing is proven with real geometries built and analyzed at the end.