Preliminary Test of Friction disk type turbine for S-CO₂ cycle application

Due to the relatively mild sodium-CO₂ interaction, the S-CO₂ Brayton cycle can reduce the accident consequence compared to the steam Rankine cycle. Also the S-CO₂ power conversion cycle can achieve high efficiency for SFR core thermal condition. Moreover, the S-CO₂ power cycle can reduce the total cycle footprint due to high density of the working fluid. However, the high pressure operating condition and low viscosity of the fluid cause difficulties in designing appropriate seals and multi-stage turbo machineries. To solve the problem for designing turbo machineries in a creative way, KAIST research team tested a friction disk type turbine concept for the S-CO₂ cycle application. In this paper, the investigation of the Tesla turbine and preliminary test results with compressed air are covered. The KAIST research team investigated a friction disk type turbine, named as Tesla turbine, for the S-CO₂ power cycle applications. Due to the robust design of the fiction disk type, the Tesla turbine technology can be utilized not only for S-CO₂ turbo machinery but also for the multi-phase or sludge flow turbo machinery. The preliminary test of lab-scale Tesla turbine with compressed air was conducted. The high pressure vessel was manufactured for the S-CO₂ operating condition. The test will be concentrated on the turbine efficiency measurement under various conditions and development of the design methodology