Simulation study of fan-beam geometry set-up for industrial gamma-ray computed tomography
Abstract
The objective of this paper is to simulate different fan-beam geometry computed tomography (CT) configurations for industrial pipe inspection. Fan-beam CT with gantry diameter of 1016 mm (40 inch) and 1270 mm (50 inch) were simulated with opening angle (δ) of 45 and 50 degrees. A digital phantom that mimics a pipe with calcium deposit along with metal rods inside was used in the simulation. From the geometry of the set-up, the maximum sample radius was calculated before the simulation. The maximum sample radius indicates the maximum pipe size the system can scan for a particular geometry. Using the reconstructed image, the maximum sample radius was approximated and it exhibited good agreement with the calculated maximum sample radius. Results showed that using a 40-inch gantry we can scan, and fully reconstruct, a pipe with 7.66-inch radius (δ = 45°) and 8.45-inch radius (δ = 50°). For a gantry size of 50 inches, the maximum pipe radius were 9.56 inches and 10.56 inches, respectively. Although it is possible to scan a pipe with radius equal to maximum sample radius, it was pointed out that giving an ample amount of allowance is a good practice.