Optimal detector position for gamma-ray backscatter density measurements

摘要

A method for determining the density of a fluid 102 in a vessel is provided. A gamma-ray source 106 is mounted onto the vessel walls 104 and emits gamma radiation 114 through the vessel wall 104 and into the fluid 102. The gamma radiation 114 is then backscattered from the fluid 102 and detected by a gamma-ray detector 110 mounted on the wall 104 at a position 112 relative to the gamma-ray source 102. The method comprises determining the optimal position of the gamma-ray detector 110 with respect to the gamma-ray source 106. The gamma-ray detector 110 is positioned at the optimal position, and the density of the fluid is measured. Determining the optimal position may comprise determining the wall thickness of the vessel, estimating the density of the fluid 102 and selecting the optimal position of the gamma-ray detector 110 based on the wall thickness and estimate of the density of the fluid 102 to maximize the precision of the density measurement.