Dynamic performance analysis of high speed flexible coupling of gas turbine engine transmission system

The high speed flexible coupling (HSFC) is used on the fighter aircraft gas turbine engines utilizing non-lubricated, metallic flexible plates. The HSFC has to transmit power at high speeds typically ranging from 10,000 to 18,000 rpm from engine gear box to accessory gear box. The HSFC also accommodates large axial and lateral misalignments due to thermal expansion and flight dynamics. The imposed angular and axial displacement distorts or bends the flexible plates. To achieve an infinite life design for HSFC, it is necessary to keep away from the different natural frequencies from the operating range of speeds apart from the optimal structural strength to accommodate larger misalignment. This paper discusses about details of system analysis, design and evaluation of HSFC for gas turbine engines. The dynamic characteristics of the HSFC are investigated through the finite element analysis (FEA) and experimental verification. The present approach can be extended for the development of similar type of flexible couplings.