A warm wind tunnel test facility operating in a transient mode was demonstrated with thin wall metal cylinders and with a thin wall linear airfoil cascade to generate local temperature variations with time which were used with a lumped parameter heat transfer assumption to calculate the external gas side heat transfer coefficients (Abuaf et al. [1995]). The present work extends the transient test methodology to Thermal Barrier Coated (TBC) thin wall metallic cylinders. The central cylinder had thermocouples imbedded and brazed in the thin metal wall and then was coated with a relatively smooth Plasma Vapor Deposited (PVD) thermal barrier coating. Transient tests were conducted at three inlet free stream turbulence intensities of 2%, 7% and 14% and at several air flow rates covering a range of Reynolds numbers from 15,000 to 100,000 based on the inlet flow conditions and the cylinder diameter. The recorded cylinder metal wall transient temperature data, were analyzed by means of an inverse conduction code. The inverse conduction code used the transient metal wall temperature data, the test cylinder geometry and the metal and TBC properties to calculate the stagnation point heat transfer coefficients acting at the surface of the TBC coating. The cylinder stagnation point Nusselt numbers are in agreement with correlations existing in the literature.

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