Abstract
Tests were performed on a mockup of a typical relief/blowdown system. The system consisted of an NPS6x8 pressure relief valve, an NPS12 tailpipe, and an NPS20 header. Small bore connections were installed in the tailpipe and header. Simple structures representing a valve mass and stiffness were attached to the small bore connections. Various industry standard tee connections between the tailpipe and header and the small-bore connections to the tailpipe and the header were studied. The goal of the testing program was to provide data to quantify the tee connection style, mitigation methods, and provide data for improvements and validation of Acoustic Induced Vibration (AIV) and Flow Induced Vibration (FIV) prediction and assessment methods. This paper describes the challenges with measuring the very high strain and vibration levels and the data processing used to extract meaningful data. The learnings about the shifting of internal acoustic modes, separating the contributions of AIV and FIV, and separating the contributions of pipe bending modes, higher order pipe modes, higher order acoustic modes, and acoustic/structural coincidence are also described. This work is connected to other presentations which focus on using the data to predict AIV and FIV in realistic blowdown systems.