Study On Radioactive Source Location And Radiation Field Reconstruction In Nuclear Radiation Environment

With the extensive application of nuclear technology and the large-scale development of nuclear energy,more and more attention has been paid to nuclear safety and radiation safety.If there is a high radioactive source with unknown location,how to locate it accurately and reconstruct the dose rate distribution of the radiation field in the whole region are important radiation safety issues in the nuclear field.At present,most of the solutions for the former problem are to search and locate the radioactive source by manual work or robots with the help of gamma ray detection instruments or other devices,while for the reconstruction of radiation field,interpolation calculation method is mostly used based on known detection points.But the above solutions are also confronted with such problems as high dose radiation can damage human body,location efficiency in some scenes is low and too many detection points required for interpolation calculation.Under this background,how to use a small number of detection points to locate the radioactive source and reconstruct the entire radiation field is studied deeply in this paper.The main tasks are as follows:(1)On the basis of full investigation of domestic and abroad relevant literature,and combining with radiation dose calculation theories,a method of radioactive source location and radiation field reconstruction based on point kernel integration is proposed.This method can estimate the location of radioactive source and give the corresponding dose rate distribution of radiation field directly by the input of detection points information,scene information and general nuclide information.(2)The technology of graphics engine,visualization,process communication are deeply studied,based on this,a radioactive source localization and radiation field reconstruction system is designed and developed,which consists of computing module,visualization module,scene management module,database module and interface module.The system can not only calculate the location of radioactive source and the dose rate distribution of radiation field,but also visualize the calculated results together with the radiation scene.In order to verify the reliability and effectiveness of the proposed method and the developed radioactive source location and radiation field reconstruction system.At the end of this paper,three simulation cases of single source without barrier,single source with barrier,double source with barrier are designed through the MCNP program.The simulation results show that the system can not only locate the radioactive source with a small error,but also the accuracy of the reconstructed radiation field is within an acceptable range.