Experimental and numerical investigations are conducted to understand the heat transfer characteristics of a double-wall film-cooled configuration. To validate the numerical method for describing the heat transfer process of the complex configuration, an infrared thermal imaging (ITI) system is used. Through the ITI system, two-dimensional temperature distributions over the coversheet of the configuration are captured. The experiments are carried out in a hot gas wind tunnel with an electrical heater of 30kW. The specimen used in the experiments has an actual size of gas turbine engines, and an integral structure of the coversheet and columnar ribs is processed by a numerically controlled milling machine. Numerical calculations are carried out by an alternant iteration algorithm between velocity field and temperature field, and the shear-stress-transport k-ω model and locally refined T-grid validated by the first part of this work are used. The numerical results are compared with the thermal image captured by the ITI system. The influences of coolant impingement and cross flow within the configuration, coolant film effect at the coversheet, heat conduction through the ribs on the overall cooling effectiveness at the coversheet are illustrated and discussed. The objective of this investigation is to provide a preparation for the next work, to estimate the thermal stress and reliability of the double-wall cooling configurations.

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