Development of a Multiple Modes Simulator of Rotating Bladed Assemblies for Blade Tip-Timing Data Analysis

Blade Tip Timing (BTT) is a promising technique for the measurement of blade-tip vibrations in bladed assemblies. After an engine test is performed, the vibration’s Engine Order (EO) and amplitude information is recovered from the collected BTT data using suitable analysis methods. The validation of such analysis methods can be carried out more conveniently on simulated BTT data. In this paper, a BTT data simulator is developed to produce controlled BTT data for bladed assemblies in which multiple modes of vibration are excited. The mathematical model used allows for multiple blade modes and multiple assembly modes to be simulated. Additionally, single or multiple, integral and non-integral EO excitations can be selected and the rotational speed of the assembly can be varied linearly. Results from several test cases are shown, demonstrating that the simulator successfully emulates assembly and blade mode combinations. A number of BTT analysis methods were able to recover with accuracy the correct EOs from the simulated BTT data