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Full-Text Articles in Mechanical Engineering
Damping And Fluidelastic Instability In Two-Phase Cross-Flow Heat Exchanger Tube Arrays, Joaquin Moran
Damping And Fluidelastic Instability In Two-Phase Cross-Flow Heat Exchanger Tube Arrays, Joaquin Moran
Publications and Scholarship
An experimental study was conducted to investigate damping and fluidelastic instability in tube arrays subjected to two-phase cross-flow. The purpose of this research was to improve our understanding of these phenomena and how they are affected by void fraction and flow regime. The model tube bundle had 10 cantilevered tubes in a parallel-triangular configuration, with a pitch ratio of 1.49. The two-phase flow loop used in this research utilized Refrigerant 11 as the working fluid, which better models steam-water than air-water mixtures in terms of vapour-liquid mass ratio as well as permitting phase changes due to pressure fluctuations. The void …
Damping Measurements In Tube Bundles Subjected To Two-Phase Cross Flow, Joaquin Moran, David S. Weaver
Damping Measurements In Tube Bundles Subjected To Two-Phase Cross Flow, Joaquin Moran, David S. Weaver
Publications and Scholarship
An experimental study was conducted to investigate twophase damping in tube arrays. The objective was to compare different measurement methodologies in order to obtain a more reliable damping estimate. This will allow for improved guidelines related to failures due to fluidelastic instability in tube bundles. The methods compared were the traditionally used halfpower bandwidth, the logarithmic decrement and an exponential fitting to the tube decay response. The working fluid used was Refrigerant 11 (Freon), which better models the real steamwater problem, as it allows for phase change. The void fraction was measured using a gamma densitometer, introducing an improvement over …