Film cooling performance of liner cooling devices

Data on the film cooling performance of several liner cooling devices are obtained over the range of velocity and density ratios relevant to gas turbines. Among the devices with tangential injection, the wiggle strip device and the machined ring with skirt construction provide the most effective film cooling. The addition of a skirt to the wiggle strip may improve its performance in the lower velocity range. The lowest effectiveness was obtained with the splash cooling arrangement which gives effective cooling of the slot lip at the expense of downstream performance. Of the discrete hole injection devices tested, the dimpled hole construction gives a significantly better performance than normal injection over a wide range of velocity ratios.