Abstract: The invention relates to a method for evaluation of fouling of passages of a spacer plate (10) of a tubular heat exchanger (11), wherein first, second and third pressure sensors (31, 32, 33) are arranged, the method comprising steps of: (a) during a transient operation phase of the heat exchanger determination of a value over time of Wide Range Level NGL, from the measurements of the first and third pressure sensors (31, 33), and of a value over time of Narrow Range Level NGE, from the measurements of the second and third pressure sensors (31, 33); (b) determination of a value over time of Steam Range Level deviation ?NGV, corresponding to the NGL from which a component representative of a variation of free water surface in the heat exchanger has been filtered, from the values of NGL and NGE; (c) comparison of the determined value of ?NGV with a set of reference profiles ?NGVi for said transient operation phase of the heat exchanger, each reference profile ?NGVi being associated with a level of fouling so

Abstract: The invention relates to a method for evaluation of fouling of passages of a spacer plate (10) of a tubular heat exchanger (11), wherein first, second and third pressure sensors (31, 32, 33) are arranged, the method comprising steps of: (a) during a transient operation phase of the heat exchanger determination of a value over time of Wide Range Level NGL, from the measurements of the first and third pressure sensors (31, 33), and of a value over time of Narrow Range Level NGE, from the measurements of the second and third pressure sensors (31, 33); (b) determination of a value over time of Steam Range Level deviation ?NGV, corresponding to the NGL from which a component representative of a variation of free water surface in the heat exchanger has been filtered, from the values of NGL and NGE; (c) comparison of the determined value of ?NGV with a set of reference profiles ?NGVi for said transient operation phase of the heat exchanger, each reference profile ?NGVi being associated with a level of fouling so

Abstract: The invention relates to a method for characterising one or more faults in a system grouping together a plurality of internal physical quantities and delimited by a plurality of boundary physical quantities, the system being modelled by a healthy model establishing relationships linking said internal physical quantities with one another and with the boundary physical quantities in the absence of a fault, a fault being defined as an alteration in the relationships linking said internal physical quantities with one another and with the boundary physical quantities with respect to the healthy model, wherein a fault is characterised by counting a number of iterations having involved said fault in a series of iterations involving a fault matrix.