Abstract: A method of superficial laser induced fluorescence for measuring film cooling performance within a fluid tunnel apparatus includes the step of introducing a test fluid uniformly dyed with a fluorescent dye into the fluid tunnel apparatus so as to surround a cooling model having a test geometry. The cooling model is positioned adjacent to a laser sheet. A background fluorescent image of the test fluid about the cooling model is recorded. The test fluid is then flushed from the tunnel apparatus. Next, a cooling simulation fluid flow and a hot gas simulation flow are introduced within the fluid tunnel apparatus. The cooling simulation fluid contains the same fluorescent dye concentration as the test fluid and the hot gas simulation fluid contains no fluorescent dye. A data image of the cooling simulation fluid flow is recorded about the cooling model as the cooling simulation fluid flow passes through the cooling model and into the hot gas simulation fluid flow.