Development of a Water-Cooled Gas Turbine

Development of water-cooled gas turbine technology was begun at General Electric in the early 1960’s, and by the early 1970’s, a small-scale turbine had been operated to temperatures of 2850 F and 16 atm, with metal temperature less than 1000 F. The Water-Cooled Turbine Development Program was begun in 1974, funded by the Electric Power Research Institute, to do preliminary design on a utility-size gas turbine using water cooling and to do basic technology development to address the problem areas. This paper presents the results of the program, including descriptions of the test hardware and data on phenomena, such as corrosion, erosion, heat transfer, and water collection. Cycle analysis results are presented for two potential combined cycle configurations: (a) one using low-Btu coal gas fuel, and (b) one using a heavy liquid fuel. Summary performance curves are given showing the effect of changes of pressure ratio and firing temperature. Methods of improving the baseline cycle and their effect on baseline performance which are judged most promising are also given on the performance curves. Turbine design features to achieve low component metal surface temperatures for increased fuels flexibility are given with particular emphasis to the first-stage nozzles and buckets. Fundamental development testing needs have been identified and programs have been put into place to bring the water-cooled turbine to a point where a full-size water-cooled turbine can be built. Descriptions of the development test facilities, task descriptions, test plans and /or test results are given for eight tasks.