Neutron Backscatter Instrument Housing Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Neutron backscatter instruments are hindered in hydrogen-rich environments like underwater settings due to high sensitivity to thermal neutrons from water, reducing their ability to detect other materials effectively.
Innovation Solution
A neutron backscatter instrument with a housing impervious to water, minimizing hydrogen-containing materials, and a neutron detector configuration that maximizes the detection of thermal neutrons scattered from objects while minimizing background noise from water, using a neutron source and detector positioned close to an external operating surface with shielding to enhance signal clarity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the neutron detector is made highly sensitive to thermal neutrons, then the ability to detect thermal neutrons from objects is improved, but the sensitivity to other materials is reduced due to large number of counts from water
Solution Approach 1:
The patent extracts and removes hydrogen-rich materials (water, polymeric buoyancy materials) from the instrument housing to eliminate the source of background neutron scattering. This allows the detector to maintain high sensitivity while reducing the overwhelming background counts from water, thereby improving the signal-to-noise ratio for detecting neutrons from target objects.
Solution Approach 2:
The patent applies local quality by creating a hydrogen-free zone within the instrument housing while allowing hydrogen-rich materials to exist in the external environment (water). The housing design ensures that only minimal hydrogen-containing materials (cables, electronics) are present, concentrating the detection capability on the target object while excluding local hydrogen interference from the instrument itself.
2Weight of moving object
If buoyancy materials such as polymeric materials are added to the housing, then the instrument's buoyancy is improved, but the detection accuracy is reduced due to hydrogen-rich material interference
Solution Approach 1:
The patent removes traditional polymeric buoyancy materials from the housing and replaces them with hydrogen-free alternatives. This extraction of harmful hydrogen-rich materials eliminates the source of background neutron scattering while maintaining the required buoyancy through alternative means, thereby preserving detection accuracy.
Solution Approach 2:
The patent employs composite material strategies by using hydrogen-free materials (such as metals or specialized composites) that provide both structural integrity and buoyancy without containing hydrogen. This allows the instrument to achieve the required buoyancy while avoiding the neutron scattering interference that would result from using conventional polymeric buoyancy materials.
3Measurement precision
If the detector is positioned close to the housing surface, then the detection of scattered neutrons from objects is improved, but the interference from hydrogen-containing materials in the housing increases
Solution Approach 1:
The patent extracts hydrogen-containing materials from the housing structure to eliminate the source of background neutron scattering. This allows the detector to be positioned close to the housing surface for improved detection efficiency without the interfering background counts that would result from hydrogen-rich materials in the housing.
Solution Approach 2:
The patent creates a local hydrogen-free environment around the detector and housing surfaces that are critical for neutron detection. By minimizing hydrogen-containing materials in these specific locations while allowing them elsewhere in minimal amounts, the patent enables close detector positioning for high detection efficiency while maintaining low background interference.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution allows for accurate detection and identification of contents within vessels, including hydrogen-rich fluids, by reducing interference from water and enhancing the detection of thermal neutrons, thereby improving the instrument's sensitivity and accuracy in underwater environments.
Implementation Method 1
emitting fast neutrons from a neutron generator into a material, then detecting and measuring the number and/or energy of the thermal neutrons scattered from the material as a result of interaction of the molecules of the material with the fast neutrons
Implementation Method 2
detecting and measuring the number and/or energy of the thermal neutrons scattered from the material
Data Source
AI summary
Disclosed is an instrument for detecting neutron backscatter from an object including a source of neutrons (12), a neutron detector (14) capable of detecting thermal neutrons and a housing (10) which is impervious to water and having at least one external operating surface (20) for placing adjacent the object, the source and detector being located within the housing in such a way that the distance between the detector and the operating surface(s) is less than 25 mm and the distance between the detector and any other external surface of the housing is at least 50 mm.