Case study: Evaluation of Steeple Dovetail Stress of Compressor Stage 3 

Stage: Stage 3 in a gas turbine compressor

Issue: Cracks were found in two serrations of the disk

Objectives: CFD and FEA analyses to evaluate the temperature and stresses in support of repair strategy



  • Cracks have been found at the dovetail corners of a shrunk-on compressor stage 3 disk.

  • Weld repair following crack removal with different machining profiles were proposed.

  • CFD and FEA were performed to evaluate the local temperature and stress fields and associated risk as a result of modifications to repair the damaged steeple.

Summary of Analyses

  • A conjugate CFD and FEA model was established to perform both structural, flow and thermal calculations simultaneously.

  • CFD and FEA analyses show that temperature and stress distributions near indications are suitable for proposed weld repair configuration when taking into account the effect of heat affected zone (HAZ) and residual stresses resulted from shrink fit.