Flow Instability Inside Heat Transfer Tubes of Moisture Separator Reheater

This paper presents some consideration and analysis on the flow instability inside the tubes of the moisture separator reheater (MSR), which is a combined equipment of the mist separator and the in-tube side condensation multi-tube type heat exchanger for superheating the exhaust from the high pressure turbine to the low pressure turbine. The condensed water in the tubes will be exhausted by the friction of excess steam vented through the tubes, and with such design, the flow in the tubes will be in an annular gas-liquid two-phase regime, ensuring the steady drainage of condensed water without subcool and the associated temperature oscillation at the tube end. The mechanism of the unstable two-phase flow dynamics in the tubes is discussed. The analysis and the results presented in this paper will be of interests to the related researchers and engineering applications.