Predicting the Onset of a Low-Frequency, Limit-Cycle Type Of Oscillatory Flow Instability in Multitube Condensing Flow

摘要

A means was developed for extending the predictive capability of the Equivalent Single- Tube Model (ESTM) to accurately predict the onset of a self-sustained oscillatory flow Instability for a multitutbe condensing flow system. The model includes the effects of compressibility, subcooled liquid inertia, and thermal and flow distribution asymmetry. Previously, liquid inertia, a necessary mechanism for the instability, had not been mod- eled for a multitube system. Extensive experimental data was obtained for a two-tube System that verifies not only the predictive capability of the ESTM, but also its accuracy And its wide range of applicability.