Study of dynamic data acquisition and processing in a novel x-ray process tomography system for rapid rotating aero-engine

In order to detect deformation of objects during the operating test, such as running aero-engine, a novel dynamic industry computed tomography (ICT) system taking advantage of the rotation of the object itself was put forward. A convenient single-trigger mode is applied to the system to acquire the complete projection data in several rotating cycles. Due to the dynamic acquisition procedure, the projection data should be sorted according to their views after the measurements. However due to the fluctuation of the aero-engine blades speed, the estimated projection angles are often slightly inaccurate and these errors are accumulated during the measurements in several rotating cycles, which eventually lead to obvious stripe artifacts in the reconstructed images. Then a posterior correction method is developed to reduce the accumulated errors for further reconstructions. The main idea of the purposed method is to carry out pre-reconstructions with few-views projections respectively to guide the accurate sort of the corresponding projections. Then a high resolution reconstructed image can be achieved with the accurately sorted projections. Simulating experiments are carried out to demonstrate the feasibility of the dynamic measurements and the effectiveness of the projection processing method. These basic researches are meaningful and useful for the following system implementations in the future.