Modelling of the droplet size distribution in a low-pressure steam turbine

Abstract

Realization of numerous tests on the droplet size measurement with extinction probe, in a 200 MW low-pressure steam turbine, provides necessary experimental data for testing the theoretical models of the droplet nucleation process in steam turbines. The earlier computational model accounting for the unsteady and viscous effects given by Bakhtar and Heaton and by Guha and Young, where the steam particles follow randomly chosen different streamlines within the blade rows with prescribed polytropic efficiency distribution in the pitchwise direction, thus undergoing various nucleation conditions, has been extended in this paper to consider to some extent two-dimensional effects. Because several uncertainties still exist in the inversion methods, predicting the size distribution of droplets, this contribution is aimed at direct comparison of the computed and measured transmittance data I/I0.

Keywords

steam turbine droplet nucleation statistical Lagrangian approach

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