Real-time detection of developing cracks in jet engine rotors

Test Devices has developed a unique method for detecting the existence of dangerous cracks in turbine engine disks. The system uses the data from two distinct sensors, a radial position sensor and an angular position reference signal. By combining these two data into a vector quantity, the system measures the displacement of the principal mass axis of the rotor. A reasoner system uses the change of principal mass axis to infer the presence of cracks. It does so by tracking changes in the unbalance as a function of the operating cycle count. The rate of change is compared with the known patterns of change produced by cracks as opposed to those produced by normal wear phenomena and other benign effects.