The NON-LINEAR CONTACT STRESS ANALYSIS OF L P COMPRESSOR BLADE-DISC ASSEMBLY FOR GAS AND CENTRIFUGAL LOAD

Abstract

Modern military aero engines set very high technology standards for the component design, as they operate in an increasingly hostile thermo-mechanical environment. With rapid advancement in materials, manufacturing processes and analytical tools, there is an increase in demands on the aero engine performance and thrust-to-weight ratio. The rotary parts like blades, disks, shafts of compressor or turbine have taken into very important consideration in gas turbine engines. As they are subjected to very high centrifugal loads and gas loads. In the present work, finite element analysis of typical conventional compressors bladed disc assembly has been carried out to study the stress levels at critical locations in discussing standard commercial finite element
software (ANSYS 10.0). Conventional bladed disc’s assembly are already operating at high stress level, because of high speed and thermal gradients across the disc bore and rim, weight optimization of disc is possible only by resorting to other techniques. A significant part of the disk weight is at blade attachment region, because the additional disk material required withstanding the centrifugal pull of the blade, an attempt has been made to find the contact stress for the weight optimized compressor bladed disc assembly. Determination of yield strength and effective comparison with the input yield strength has been done. This observation clearly shows that compressor blade and disk are in safe position from the crack initiation. The peak values of compressive stresses also induced near the region of contact stresses are also well within the design limit1. The peak value of von-misses stresses induced near the region of contact stresses are also well within the design limit.