UNSTEADY MULTISTAGE ANALYSIS USING A LOOSELY-COUPLED BLADE ROW APPROACH

The flow through gas-turbine compressors and turbines is dominated by unsteady and viscous phenomena. Accurately predicting the behavior of these complex multistage flows with unsteady rotor-stator interacting Navier-Stokes analyses can require enormous computer resources. In thi s investigation, an alternative method for calculating the unsteadines s associated with multiple-stage turbomachinery hows is presented. The method, called the loosely coupled blade row (LCBR) technique, utiliz es single-blade row simulations coupled with the appropriate unsteady boundary conditions to predict the aerodynamic interaction effects of adjacent blade rows. The LCBR approach provides an efficient alternati ve to fully coupled interaction analyses while maintaining comparable accuracy.