Flow Stability of Heat Recovery Steam Generators

In this paper the results of a theoretical stability analysis are presented. The investigation was done for two different types of natural circulation Heat Recovery Steam Generators (HRSG) — a two-drum steam generator and a HRSG with a horizontal tube bank. The investigation shows the influence of the boiler geometry on the stability of the steam generators. For the two-drum boiler the static instability, namely the reverse flow is analysed. First results of the investigations for the HRSG with a horizontal tube bank are also presented. In this case the dynamic flow instability of density wave oscillations is analysed.