Method and system for real-time monitoring of wall thinning and ascertaining of wall attributes using fiber Bragg grating (FBG) sensors

A system for ascertaining at least one attribute of pressure vessel wall, the system comprising:

• a plurality of fiber Bragg grating (FBG) sensors which are disposed at outer surface locations on a pressure vessel which comprises a wall having an outer surface and an inner surface, wherein the FBG sensors include a first FBG sensor disposed at a first outer surface location on the pressure vessel;
• and
• a computing processor which is communicably coupled via a communication network to the FBG sensors, wherein the computing processor is configured to:
• while the pressure vessel is operating:
• ascertain a current wavelength shift of the first FBG;
• and
• ascertain a current thickness of the wall at the first outer surface location by:
• computing a vector based on a time series of the current wavelength shift, or a derivative of the time series, or a derivative of the current wavelength shift;
• providing the vector to a predetermined regression model;
• and
• using the regression model, ascertaining the current thickness of the wall;
• and
• based on the time series of the current wavelength shift, compute a current summation of absolute changes thereof and/or a current gradient thereof;
• and
• classify the current condition as an overthinning condition if the current summation, or the gradient, or a combination of the current summation and the gradient satisfies a threshold condition which is selected from the group consisting of at least one previous summation of absolute changes in previous wavelength shift of the first FBG sensor, at least one previous gradient of previous wavelength shift of the first FBG sensor, at least one predetermined threshold value, and a predetermined threshold line, wherein the overthinning condition identifies an impending failure of the pressure vessel.