CGT301 is a recuperated, single-shaft ceramic gas turbine for co-generation use. Ceramic parts are used in the hot section of the engine, such as turbine blades, nozzle vanes, combustor liners, heat exchanger elements and gas path parts. These ceramic parts are designed axi-symmetrically to reduce their sizes and thermal stresses and to avoid their unexpected deformations. The turbine is a two-stage axial flow type. As a primary feature of this turbine, the rotors are composed of ceramic blades inserted into metallic disks. The ceramic parts of the engine system have been tested before installing them in the engine to assure their reliability in the following manner. The ceramic blades have been examined by hot-spin test with the gas temperature of 1100°C and up to 110% of the engine rated speed. The ceramic stationary parts such as nozzle vanes, combustor liners and gas path parts, have been assembled and installed in a test rig with almost the same constraint and thermal conditions as the engine, and thermal fatigue tests of 100 cycles between 1200°C and 300°C have been conducted. After the proof tests of ceramic parts, they have been installed in the engine, step by step. Finally, the engine has been operated with a TIT of 1200°C at the engine rated speed of 56000 rpm. The present paper describes the development process and shows test results of the ceramic gas turbine at a TIT of 1200°C.

The CGT301 ceramic gas turbine is being developed under a contract from NEDO as a part of the New Sunshine Program of MTTI to improve the performance of gas turbines for cogeneration through the replacement of hot section components with ceramic parts. The project is conducted in three phases. The project currently in Phase 2 focuses on the development of the “primary type” ceramic gas turbine (turbine inlet temperature: 1,200°C). CGT301 is a recuperated, single-shaft, ceramic gas turbine. The turbine is a two-stage axial flow type. The major effort has been on the development of the turbine which consists of metallic disks and inserted ceramic blades (“hybrid rotor”). Prior to engine tests, component tests were performed on the hybrid rotor to prove the validity of the design concepts and their mechanical integrity. The engine equipped with all ceramic components except the second stage turbine blades was tested and evaluated. The engine was operated successfully for a total of 23 hours without failure at the rated engine speed of 56,000 rpm with the turbine inlet temperature of 1,200 °C. Further, the engine equipped with all ceramic components was successfully tested for one hour under the same conditions. Engine testing of the “primary type” ceramic gas turbine is continuing to improve the performance and the reliability of the system for the purpose of moving forward to the development of the “pilot” ceramic gas turbine (turbine inlet temperature: 1,350 °C) as the final target of this project. This paper summarizes the progress in the development of the CGT301 with the emphasis on the test results of the hybrid rotor.

CGT301 ceramic gas turbine is being developed under a contract from NEDO as a part of the New Sunshine Program of MITI to improve the performance of gas turbine for co-generation through the replacement of the hot section components with ceramic parts. CGT301 is a recuperated, single-shaft ceramic gas turbine. We have been developing some unique technologies, such as the “hybrid” rotor, composed of a metal disk and inserted ceramic blades, considering the future applicability to larger gas turbines. We could attain the good engine performance with the primary type CGT at a TIT of 1,200°C. The reliability of the hybrid rotor was confirmed at a TIT of 1,350°C on the test rig. We conducted preliminary tests using the primary type CGT to extract the possible problems derived from the higher TIT. Some modifications were made and the engine operation at a TIT of 1,280°C was conducted successfully. On the basis of those experiences we finished the design and fabrication of the pilot CGT. This paper presents the progress in the development of CGT301.

The CGT301 ceramic gas turbine has been developed under a contract from NEDO as a part of the New Sunshine Program of MITI since 1988 to 1998. The CGT301 is a recuperated, single-shaft ceramic gas turbine. Ceramic parts are used in the hot section of the engine, such as turbine blades, nozzle vanes, combustion liners and so on. As a primary feature of this turbine, the rotors are composed of ceramic blades inserted into metallic disks (“hybrid rotor”) for the future applicability to the large gas turbine. The R & D program consists of three phases, the model metal gas turbine, the primary type ceramic gas turbine and the pilot ceramic gas turbine. The pilot ceramic gas turbine showed etable operation at TIT of 1,350°C. This paper presents the progress in the development of the pilot ceramic gas turbine of CGT301.