AN EXPERIMENTAL AND THEORETICAL STUDY OF DENSITY-WAVE OSCILLATIONS IN TWO-PHASE FLOW.
Topical rept. Jun 68-Dec 69,
MASSACHUSETTS INST OF TECH CAMBRIDGE ENGINEERING PROJECTS LAB
Pagination or Media Count:
A theoretical and experimental investigation of fundamental aspects of density-wave oscillations was undertaken. The experimental Freon-113 loop was operated at atmospheric pressure level with constant pressure drop across a single test channel. A wide range of inlet temperatures, flows and heat inputs was covered. The regions of unstable operation of the channel were mapped for both uniform and cosine heat flux distributions. The effect of the cosine distribution was stabilizing. The period of the oscillations was approximately equal to twice the transit time, defined as the sum of one half the residence time of a fluid particle in the single-phase region plus the vapor transit time in the two-phase region. At high subcoolings and low power levels unexpected higher-order oscillations were detected. Analytically the stability of the channel is investigated by oscillating the inlet flow. The theoretical procedures used for predicting the steady-state condition in the boiling channel were tested by extensive pressure drop measurements. The predictions of the stability model are compared to the experimental observations. Author
- Fluid Mechanics