Abstract: The turbine end support is of great significance in designing the shafting system of the heavy-duty gas turbine. The thermal adaptive alignment mechanism of the tangential support is investigated based on the fluid-solid coupling finite element method. 3-dimensional models of the tangential struts，diffuser cones, hot gas and cooling air are established through Pro/Engineering software. Then by defining the fluid-solid interfaces, a CFD analysis is carried out considering both the structural characteristics of support and the properties of fluids. With the calculated solid temperature field provided as thermal loads, a structural analysis is presented to obtain the thermal deformation and stress distributions of the tangential support through ANSYS software. 8 testing points on the support are selected to monitor deformations. By comparison, the results show that thermal deformations of the support are automatically eliminated though mandatory rotating on the bearing house imposed by the tangential plates, thus decrease the deviation of the center and achieve the adaptive alignment at thermal state. This is a very fundamental study on the optimization design and experiment of the support of gas turbine.

Key words: alignment mechanism, fluid-solid coupled, gas turbine, tangential support, thermal stress