Static Analysis and Health Monitoring of Pipelines in NPPs with Noise Consideration

Abstract

The study proposes a numerical methodology for assessment of physical parameters which are critical to damage detection and structural health monitoring of pipelines propagating fluids under high temperatures. The thermal gradient of the fluid, self-weight of the piping system, and the pressure exerted on the pipe walls are taken into consideration for static analysis. The displacement, stresses and strains are computed for the imposed loads. The boundary conditions for a pipeline element is assigned through translational and rotational springs whose stiffnesses are unknown. The expression for the boundary stiffnesses are derived by coupling the internal pressure due to fluid flow with thermal loading and weight. The dependent and independent parameters for deciphering the degradation of the pipe element are identified to minimize instrumentation for health monitoring. The primary aspects of damage being investigated are wall thinning due to corrosion resulting in stiffness degradation. In practical scenarios, it has been observed that excessive instrumentation of a structural component for health monitoring, might result in measurement noise. Hence, artificial noise is introduced to the measurement stresses and strains in a Gaussian distribution form, which is corrected through a numerical algorithm.