WO2020057457A1

WO2020057457A1 - Neutron source photographic system for vehicle-mounted proton linear accelerator

Info

Publication number: WO2020057457A1
Application number: PCT/CN2019/105934
Authority: WO
Inventors: 王盛; 李晓博; 马宝龙; 杜鑫; 大竹淑惠; 须长秀行; 王洁
Original assignee: 西安交通大学
Priority date: 2018-09-19
Filing date: 2019-09-16
Publication date: 2020-03-26
Also published as: CN109152193A

Abstract

A neutron source photographic system for a vehicle-mounted proton linear accelerator, comprising an ion source (4), a proton linear accelerator (5), a neutron photographic device (7), a central control and data acquisition processing system (3), a target station (6), and a power source (2) for supplying energy. The target station (6) comprises a shielding cover (63), a lithium target, a magnetic deflection device (62), and a neutron collimator (64); a proton beam produced by the ion source (4) is accelerated by the proton linear accelerator (5), deflected by the magnetic deflection device (62), and then bombarded onto the lithium target (61), causing the lithium target (61) to produce a neutron beam, the neutron beam produced by the lithium target (61) passes through the neutron collimator (64) and then bombards an object to be measured, the neutron photographic device (7) receives the neutron reflected by the object to be measured, and an output end of the neutron photographic device (7) is connected to the central control and data acquisition processing system (3). The photographic system has a low requirement for shielding and high neutron production efficiency, and can implement vehicle-mounted operation.

Description

Neutron source camera system for vehicle proton linear accelerator

[Technical Field]

The invention belongs to the field of engineering technology design, and relates to a neutron source camera system for a vehicle-mounted proton linear accelerator.

【Background technique】

Neutron photography is an excellent non-destructive testing technique. Neutrons are uncharged and highly penetrable. They can distinguish between isotopes, light elements, and neighboring elements. After passing through the measured object, the difference in the structure of the object or the difference in the material will cause different intensity attenuation. By detecting the transmitted neutron intensity distribution, information such as the internal structure and material distribution of the object can be obtained. The use of neutron photography technology for non-destructive testing of measured objects and objects has great development potential in industrial and engineering applications.

Based on a small accelerator neutron source that is small in size, light in weight, and relatively easy to operate and control, it can be further miniaturized to realize on-board vehicle, and it is very convenient to carry out neutron photography work at the desired work site, and realize the bridge, dam, Defect inspection of internal structures such as tunnels, corrosion detection of aviation components, and detection and analysis of explosives. The realization of the on-board accelerator neutron source camera system can greatly expand the use of neutron sources, and can easily carry out neutron non-destructive testing and neutron imaging at the work site, and realize the special buildings, bridges, dams, and tunnels. , Rail transportation, pressure vessels, nuclear power facilities, aircraft, rockets and other in-service inspections. This is of great significance to promote the progress of China's scientific research level and promote national economic and social development.

The research and development of the movable neutron imaging detector based on the neutron tube using the DT reaction scheme by the China Academy of Engineering Physics in China is nearing completion. The estimated neutron output is 1011n / s, which aims to achieve a fast 14MeV. Neutron photography. However, the product of the D-T reaction is relatively radioactive and requires high shielding requirements, which may cause the weight of the entire vehicle system to increase significantly, affecting safety and mobility. At the same time, the efficiency of neutron generation is low through this reaction.

[Summary of the Invention]

The purpose of the present invention is to overcome the shortcomings of the prior art described above, and provide a vehicle-mounted proton linear accelerator neutron source camera system. The camera system has lower requirements for shielding, and has a higher efficiency for generating neutrons. Into.

In order to achieve the above object, the vehicle-mounted proton linear accelerator neutron source camera system of the present invention includes an ion source, a proton linear accelerator, a neutron camera device, a central control and data acquisition and processing system, a target station, and a power source for providing energy. ; The target station includes a shielding cover and a lithium target, a magnetic deflection device and a neutron collimator arranged in the shielding cover;

The proton beam generated by the ion source is accelerated by the proton linear accelerator and deflected by the magnetic deflection device and then bombarded on the lithium target, so that the lithium target generates a neutron beam, and the neutron beam generated by the lithium target is bombarded by the neutron collimator. The neutron camera receives the neutrons reflected by the object to be measured, and the output of the neutron camera is connected to the central control and data acquisition and processing system;

The output of the central control and data acquisition and processing system is connected to the control of the ion source, the control of the proton linear accelerator, the control of the magnetic deflection device and the control of the neutron camera.

It also includes a carrier vehicle, in which the middle part of the carrier vehicle is provided with a radiation protection door. Among them, the power source and the central control and data acquisition and processing system are located on the front side of the vehicle compartment, and the ion source, proton linear accelerator and target station are located behind the vehicle compartment. Side, and the ion source, proton linear accelerator, and target station are arranged from front to back, the neutron camera is located directly below the target station, and the neutron camera is located at the bottom of the carriage.

The proton linear accelerator is in communication with the ion source and the lithium target through a vacuum conduit, and the magnetic deflection device is located on the side of the vacuum conduit.

The proton beam generated by the ion source is accelerated by a proton linear accelerator and deflected by a magnetic deflection device at 90 °, and then bombards the lithium target.

The proton linear accelerator is an RFQ proton linear accelerator.

The material of the radiation protection door and the shielding cover is lead boron polyethylene.

The neutron collimator is made of polyethylene.

The bottom of the lithium target is provided with a circular groove, and the upper end of the neutron collimator is embedded in the circular groove.

The invention has the following beneficial effects:

The neutron source camera system of the vehicle-mounted proton linear accelerator according to the present invention uses a proton linear accelerator to accelerate the proton bombardment of a lithium target to generate neutrons during specific operations. The proton linear accelerator has better acceleration performance for charged particles and high capture efficiency. In addition, the volume is small, and the mass of protons as incident particles is small, and it is easy to be accelerated to the ideal speed. At the same time, the required transmission power is low, and it is easier to realize vehicle-mounted. In addition, after the proton beam is accelerated, the direction of the proton beam is adjusted by the magnetic deflection device, so that most of the emitted neutrons are emitted downward, which is suitable for the detection environment of most infrastructures. In addition, the invention uses a lithium target as a target system, and under the bombardment of a proton beam of 2.5-4 MeV and 100 uA, it can achieve a high neutron yield of 1011-1012 n / s, thereby speeding up the photographing speed of the object to be measured and improving the imaging effect. In addition, the lithium target has no mobility, the reaction products are weak in radioactivity, the radioactive hazard is controllable, and the requirements for system shielding are low. All shielded neutrons and gamma rays are shielded by the shield to ensure the safety of surrounding personnel and the environment.

[Brief Description of the Drawings]

FIG. 1 is a schematic structural diagram of the present invention;

FIG. 2 is a schematic diagram of the present invention.

Among them, 1-carriage vehicle; 2-power source; 3-central control and data acquisition and processing system; 4-ion source; 5-proton linear accelerator; 6-target station; 61-lithium target; 62-magnetic deflection device; 63 -Shield; 64-neutron collimator; 7-neutron camera.

【detailed description】

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only The embodiments which are part of the present invention are not all the embodiments, and are not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts disclosed in the present invention. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts should fall within the protection scope of the present invention.

Various structural diagrams according to the disclosed embodiments of the present invention are shown in the drawings. These figures are not drawn to scale, with some details exaggerated for clarity and some details may be omitted. The shapes of the various regions, layers, and their relative sizes and positional relationships shown in the figure are only exemplary. In practice, there may be deviations due to manufacturing tolerances or technical limitations. It is possible to design additional regions / layers with different shapes, sizes, and relative positions.

In the context of the present disclosure, when a layer / element is referred to as being “on” another layer / element, the layer / element may be directly on the other layer / element, or intervening layers / element. In addition, if one layer / element is "above" another layer / element in one orientation, that layer / element may be "below" the other layer / element when the orientation is reversed.

It should be noted that the terms “first” and “second” in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data so used may be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in an order other than those illustrated or described herein. Furthermore, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or device that includes a series of steps or units need not be limited to those explicitly listed Those steps or units may instead include other steps or units not explicitly listed or inherent to these processes, methods, products or equipment.

The present invention is described in further detail below with reference to the drawings:

Referring to FIG. 2, a vehicle-mounted proton linear accelerator neutron source camera system according to the present invention includes an ion source 4, a proton linear accelerator 5, a neutron camera device 7, a central control and data acquisition processing system 3, a target station 6, and a device for providing Power source 2 of energy; target station 6 includes a shield 63 and a lithium target 61, a magnetic deflection device 62, and a neutron collimator 64 provided in the shield 63; the proton beam generated by the ion source 4 is accelerated by the proton linear accelerator 5 And the magnetic deflection device 62 deflected and bombarded the lithium target 61, so that the lithium target 61 generated a neutron beam. The neutron beam generated by the lithium target 61 passed the neutron collimator 64 and bombarded the object to be measured. The neutron camera 7 received The neutron reflected by the object to be measured, the output of the neutron camera 7 is connected to the central control and data acquisition and processing system 3; the output of the central control and data acquisition and processing system 3 is connected to the control terminal and proton of the ion source 4 The control end of the linear accelerator 5, the control end of the magnetic deflection device 62 and the control end of the neutron camera 7 are connected.

As shown in FIG. 1, the present invention also includes a carrier vehicle 1, wherein a radiation protection door is provided in the middle of the carriage of the carrier vehicle 1, wherein a power source 2 and a central control and data acquisition processing system 3 are located on the front side of the carriage, and an ion source 4. The proton linear accelerator 5 and the target station 6 are all located on the rear side of the carriage, and the ion source 4, the proton linear accelerator 5 and the target station 6 are arranged in order from front to back. The neutron camera 7 is located directly below the target station 6, The neutron camera 7 is located at the bottom of the carriage.

The proton linear accelerator 5 communicates with the ion source 4 and the lithium target 61 through a vacuum conduit, and the magnetic deflection device 62 is located on the side of the vacuum conduit; the proton linear accelerator 5 is an RFQ proton linear accelerator; the material of the radiation protection door and the shield 63 The neutron collimator 64 is made of polyethylene; the bottom of the lithium target 61 is provided with an annular groove, and the upper end of the neutron collimator 64 is embedded in the annular groove.

In actual use, the operator drives the transport vehicle 1 to the detection position, so that the neutron camera 7 is being measured, wherein the exit of the neutron collimator 64, the neutron camera 7 and the target to be measured are on the same straight line. . Then open the central control and data acquisition and processing system 3, provide power through the power source 2, and then control the ion source 4 to generate a proton beam with sufficient current intensity. The proton beam enters the proton linear accelerator 5 through a vacuum duct and is accelerated to the required energy ( 2.5-4 MeV), and then enter the target station 6 through the vacuum catheter.

In the target station 6, after the proton beam is deflected 90 ° downward by the magnetic deflection device 62, the horizontally placed lithium target 61 is bombarded to generate a neutron beam, and the neutrons emitted forward are led out by the neutron collimator 64, and then The neutron camera 7 is bombarded by the neutron camera 7 while the remaining neutrons are shielded by the shield 63. The neutron camera 7 is used to receive the neutrons reflected from the interaction with the object to be measured, and then transmits the signal to the central control and data acquisition and processing system 3 for data processing and analysis, so as to obtain detailed information about the object to be measured. Data and graphs to grasp information such as the internal structure, elemental composition, and stress distribution of the object to be measured, and realize the photography and non-destructive testing of the object to be measured.

The above content is only for explaining the technical idea of the present invention, and cannot be used to limit the protection scope of the present invention. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls into the claims of the present invention. Within the scope of protection.

Claims

An on-board proton linear accelerator neutron source camera system is characterized by comprising an ion source (4), a proton linear accelerator (5), a neutron camera device (7), a central control and data acquisition and processing system (3), and a target. Station (6) and a power source (2) for providing energy; the target station (6) includes a shield cover (63) and a lithium target (61), a magnetic deflection device (62) and Neutron Collimator (64);

The proton beam generated by the ion source (4) is accelerated by the proton linear accelerator (5) and deflected by the magnetic deflection device (62) and bombarded on the lithium target (61), so that the lithium target (61) generates a neutron beam and the lithium target (61 The neutron beam generated by the neutron collimator (64) bombards the object to be measured. The neutron camera (7) receives the neutrons reflected by the object to be measured. The output of the neutron camera (7) and Central control and data acquisition and processing system (3) are connected;

The output of the central control and data acquisition and processing system (3) and the control of the ion source (4), the control of the proton linear accelerator (5), the control of the magnetic deflection device (62), and the neutron camera (7) The control terminals are connected.
The on-board proton linear accelerator neutron source camera system according to claim 1, further comprising a carrier vehicle (1), wherein a radiation protection door is provided in the middle of the carriage of the carrier vehicle (1), wherein the power source ( 2) and the central control and data acquisition and processing system (3) are located on the front side of the carriage, the ion source (4), the proton linear accelerator (5) and the target station (6) are located on the rear side of the carriage, and the ion source (4) The proton linear accelerator (5) and the target station (6) are arranged in sequence from front to back. The neutron camera (7) is located directly below the target station (6), and the neutron camera (7) is located at the bottom of the carriage.
The on-vehicle proton linear accelerator neutron source camera system according to claim 1, wherein the material of the radiation protection door and the shielding cover (63) is lead boron polyethylene.
The on-board proton linear accelerator neutron source camera system according to claim 1, characterized in that the proton linear accelerator (5) is connected to the ion source (4) and the lithium target (61) through a vacuum conduit, and the magnetic deflection The device (62) is located on the side of the vacuum conduit.
The on-board proton linear accelerator neutron source camera system according to claim 1, characterized in that the proton beam generated by the ion source (4) is accelerated by the proton linear accelerator (5) and the magnetic deflection device (62) is deflected by 90 ° and bombarded Onto the lithium target (61).
The vehicle-mounted proton linear accelerator neutron source camera system according to claim 1, wherein the proton linear accelerator (5) is an RFQ proton linear accelerator.
The on-board proton linear accelerator neutron source camera system according to claim 1, wherein the neutron collimator (64) is made of polyethylene.
The vehicle-mounted proton linear accelerator neutron source camera system according to claim 1, characterized in that the bottom of the lithium target (61) is provided with a circular groove, and the upper end of the neutron collimator (64) is embedded in the ring Inside the groove.