A PERFORATED SHEET AND A METHOD OF MAKING THE SAME

摘要

A perforated sheet for the promotion of film cooling a gas turbine engine comprises two separate layers of laminate material which are placed in superposed abutting relationship. The first layer has a plurality of apertures of given cross-sectional area therein. The second layer also has a plurality of apertures therein which have larger cross-sectional areas than the corresponding apertures in the first layer. The apertures in the first layer are in fluid communication with the apertures in the second layer to form passageways through the perforated sheet. These passageways permit a cooling flow of fluid to pass through the perforated sheet so it can be discharged as a cooling fluid film along the inner surface of the perforated sheet. The apertures in each layer are independently formed to produce the passageways. The apertures can easily be machined to the desired size, shape, and angle to optimize the cooling film effectiveness for any particular application.