Most non-equilibrium wet steam CFD analyses in the open literature have concentrated on predicting blade pressure loadings, with very few studies emphasizing turbine efficiencies. One of the few exceptions is the work of Gerber et al. [1]. In light of this, in this paper we present CFD predictions of isokinetic efficiency and Markov Loss coefficients and comparisons with measurements for the 2D cascades of White et al. [2] and Bakhtar et al. [3, 4]. Predictions were obtained using an Eulerian-Eulerian multiphase formulation, which is an extension of General Electric’s proprietary CFD turbomachinery code, TACOMA. The formulation is optimized to capture the thermodynamic loss. There is no slip between the droplets and the surrounding vapor. Comparisons with other experimental quantities are also presented as needed to ensure that the non-equilibrium wet steam physics is accurately captured. Although the non-equilibrium models used cannot capture all the loss components present in actual flows, our efficiency predictions are much closer to experimental data than those of equilibrium simulations or the Baumann rule.
Phase Transitions in Equilibrium and Non-Equilibrium Models on Some Topologies
