Review on Fir-Tree Joint of Turbine Disc In Aero Engine

Abstract

Now a day?s the fir-tree joint is very much evident from the literature that not much work carried out on effect of cooling passage of fir-tree root joint of turbine disk. The method of attaching the blades to the turbine disk is of considerable important, since the stress in the disk around the fixing or in the blade root has an important bearing on the limiting rim speed. On earlier days, whittle engine were attached by the dovetail fixing but this design was soon superseded by the fir -tree fixing that is now used in majority of gas turbine engines. The fir-tree fixing type involves very accurate machining to ensure that the loading is shared by all the serrations. When the turbine is stationary, then the blade is free in the serrations and is stiffened in the root by centrifugal loading when the turbine is rotating. This paper proposed the work on the development of geometric model of disc and blades for turbine.