A Three-Dimensional Coupled Internal/External Simulation of a Film-Cooled Turbine Vane

Abstract

A three-dimensional Navier-Stokes simulation has been performed for a realistic film-cooled turbine vane using the LeRC-HT code. The simulation includes the flow regions inside the coolant plena and film cooling holes in addition to the external flow. The vane is the subject of an upcoming NASA Lewis Research Center experiment and has both circular cross-section and shaped film cooling holes. This complex geometry is modeled using a multi-block grid which accurately discretizes the actual vane geometry including shaped holes. The simulation matches operating conditions for the planned experiment and assumes periodicity in the spanwise direction on the scale of one pitch of the film cooling hole pattern. Two computations were performed for different isothermal wall temperatures, allowing independent determination of heat transfer coefficients and film effectiveness values. The results indicate separate localized regions of high heat flux in the showerhead region due to low film effectiveness and high heat transfer coefficient values, while the shaped holes provide a reduction in heat flux through both parameters. Hole exit data indicate rather simple skewed profiles for the round holes, but complex profiles for the shaped holes with mass fluxes skewed strongly toward their leading edges.

Conjugate heat transfer analysis of film cooling flows

“…Fig.4 compares the centerline, midline and spanaveraged temperature profiles predicted using Eqs. (8) and (12～15) with the experimental data. The centerline temperature is defi s, with the midline temperature defined on a line centered between holes.…”

“…Complex 3-D numerical investigations of a real film-cooled blade were presented by Garg and Rigby [7] with a focus on the hole exit regions and the heat transfer. Heidmann et al [8] computed the heat transfer for a realistic turbine vane with 12 rows of holes with shaped holes and the plena. Garg [9] presented results for a full rotating blade with 172 film holes, resolving the film hole exits, but not the hole pipes and plena.…”

Stability analysis of partitioned methods for predicting conjugate heat transfer

“…Divo et al [9,13] and Heidmann et al [14,15] report on the use of the TFFB method for the computation of the conjugate heat transfer effects on a realistic film-cooled turbine blade. The method uses an explicit FVM code and a Boundary Element Method (BEM) for the computation of the heat transfer in the solid.…”

Numerical investigation of the effectiveness of effusion cooling for plane multi-layer systems with different base-materials

“…Numerical investigations of entire blades with film cooling configurations have been presented by Garg [5] and by Heidmann et al [6]. These investigations also focused on the purely aerodynamic effects of cooling fluid flow on main flow field.…”