Field investigations examining the impact of supersaturated vapor expansions on turbine performance

摘要

Investigators in the Heat Cycle Research project are developing a technology base which will permit the increased utilization of the moderate-temperature, liquid-dominated geothermal resource for the production of electrical power. The project investigations have focused upon power cycles which have the potential for the increased utilization (power produced per unit quantity of fluid) of the hydrothermal resource. The investigations to date have confirmed the viability of technology required to incorporate concepts which will allow the binary power cycle to have a performance approaching practical thermodynamic maximums. Investigations in progress are examining the potential improvements that result from allowing super-saturated turbine expansions. During these metastable expansions, the working fluid is maintained as a supersaturated vapor during the turbine expansion process; if at equilibrium conditions, liquid condensate would be present. If it can be shown that these expansions proceed without a degradation in turbine performance or damage to the turbine internals by any condensate which forms, a projected 8% improvement in the performance of the advanced cycle could be realized. Investigators are presently examining the condensation behavior of these expansions, as well as determining the impact of these expansions on turbine performance.