Aerodynamic Investigation of External Cooling and Applicability of Superposition
(English)Manuscript (preprint) (Other academic)
An experimental investigation of the overall external cooling on a cooled nozzle guide vanehas been conducted in a transonic annular sector cascade. The investigated vane is a typicaltransonic high pressure gas turbine vane, geometrically similar to a real engine component.The investigations are performed for various coolant-to-mainstream mass-flux ratios. Resultsindicate that the aerodynamic loss is influenced substantially with the change of the coolingflow. Area-averaged exit flow angles in midspan region are unaffected at moderate filmcoolant flows, for all cooling configurations except for trailing edge cooling. The trailing edgecooling decreases the turning in all investigated cases. Results lead to a conclusion that bothtrailing edge and suction side cooling have significant influence on the aerodynamic losswhereas the shower head cooling is less sensitive to the loss. Investigations with individualcooling features essentially lead to the applicability of the superposition technique regardingthe aerodynamic loss for film cooled vanes, which is this paper’s contribution to the researchfield. Results show that the superposition technique can be used for the profile loss but not forthe secondary loss.
Aerodynamic loss, film cooling, trailing edge cooling, nozzle guide vane, superposition
Aerospace Engineering Applied Mechanics Energy Engineering
Research subject Aerospace Engineering; Energy Technology
IdentifiersURN: urn:nbn:se:kth:diva-150455OAI: oai:DiVA.org:kth-150455DiVA: diva2:743460
Manuscript submitted to Proceedings of the 11th European Conference on Turbomachinery Fluid Dynamics and Thermodynamics (ETC), 2015, Madrid, Spain. QS 20142014-09-042014-09-042014-09-09Bibliographically approved