Speckle-interferometry in the Investigation of Large-size Gas Turbine Engine Structures Vibration

A speckle-interferometer plant has been developed to investigate bladed turbo-machinery wheels vibration. A plant optical arrangement and an object under investigation are placed on a massive holographic plate. Turbine wheel vibration frequencies and modes of one of the aircraft engines are given which have been obtained using this plant. Another speckle-interferometer has been designed requiring no interferometer plate (table) to investigate part vibration under working area conditions. With the help of this plant, investigation of fan blades lot vibration frequencies and modes has been performed.