Indirect neutron radiography experiment on dummy nuclear fuel rods for pressurized water reactors at CMRR

Nuclear energy is a vital source of clean energy that will continue to play an essential role in global energy production for future generations. Nuclear fuel rods are core components of nuclear power plants, and their safe utilization is paramount. Due to its inherent high radioactivity, indirect neutron radiography (INR) is currently the only viable technology for irradiated nuclear fuel rods in the field of energy production. This study explores the experimental technique of indirect neutron computed tomography (INCT) for radioactive samples. This project includes the development of indium and dysprosium conversion screens of different thicknesses and conducts resolution tests to assess their performance. Moreover, a pressurized water reactor (PWR) dummy nuclear fuel rods have been fabricated by self-developing substitute materials for cores and outsourcing of mechanical processing. Experimental research on the INR is performed using the developed dummy nuclear fuel rods. The sparse reconstruction technique is used to reconstruct the INR results of 120 pairs of dummy nuclear fuel rods at different angles, achieving a resolution of 0.8 mm for defect detection using INCT.