Superficial laser induced fluorescence

A method of superficial laser induced fluorescence for measuring film cooling performance within a fluid tunnel apparatus, comprising the following method steps:

• introducing a test fluid uniformly dyed with a fluorescent dye into said fluid tunnel apparatus so as to surround a cooling model having a test geometry, said cooling model being disposed adjacent to a laser sheet;
• recording a background fluorescent image of said test fluid about said cooling model;
• flushing said test fluid from said fluid tunnel apparatus;
• introducing a cooling simulation fluid flow within said fluid tunnel apparatus, said cooling simulation fluid having substantially the same fluorescent dye concentration as said test fluid;
• introducing a hot gas simulation fluid flow within said fluid tunnel apparatus, said hot gas simulation fluid flow having no fluorescent dye;
• recording a data image of said cooling simulation fluid flow about said cooling model as said cooling simulation fluid flow passes through said cooling model and into said hot gas simulation fluid flow;
• correcting said data image with said background fluorescent image so as to determine superficial flow characteristics of said cooling simulation fluid flow passing through said cooling model.