In supersonic two-phase flows of steam, under the influence of rapid expansion, the vapor becomes supersaturated. Following this condition the nucleation happens in the vapor phase and the formed tiny droplets grow along the passage and therefore the condensation phenomenon happens. The effects of the condensation phenomenon in power steam turbines include efficiency drop and mechanical damages. In the previous work of the authors, volumetric heating was introduced as an approach for reducing the mentioned damages and losses. However, further investigations revealed that heating decreases the mass flow rate, which can be increased with adjusting the inlet stagnation pressure. In this paper, using a semi-analytical and a one dimensional modeling approach, the simultaneous effects of volumetric heat transfer and inlet stagnation pressure variation are investigated in order to remedy the mass flow rate reduction. The results show that increasing the inlet stagnation pressure up to 5 percent can fix the mass flow rate of the non-adiabatic flow, compared to the adiabatic flow for the same conditions.

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