Research and Development of Ceramic Gas Turbine (CGT302)

The ongoing Japanese Ceramic Gas Turbine (CGT) project, as a part of the New Sunshine Project funded by the Ministry of International Trade and Industry (MITI), aims to achieve higher efficiency, lower pollutant emission, and multifuel capability for small to medium sized gas turbine engines to be used in cogeneration systems. The final target of this project is to achieve a thermal efficiency over 42 percent at a turbine inlet temperature (TIT) of 1350°C. Under this project, Kawasaki Heavy Industries (KHI) is developing the CGT302 (a regenerative twin-spool CGT). The CGT302 has several unique features: simple-shaped ceramic components, KHI’s original binding system for turbine nozzle segments, stress-free structure using ceramic springs and rings, etc. In addition to these features, a high turbine tip speed and a metal plate fin recuperator were adopted. At the end of the fiscal year 1994, an intermediate appraisal was carried out, and the CGT302 was recognized to have successfully achieved its target. The CGT302 endurance test at the intermediate stage required 20 hours’ operation of the basic ceramic engine. The actual testing accomplished 40 hours at over 1200°C TIT, which included 30 hours of operation without disassembling. The target thermal efficiency of 30 percent at 1200°C has almost been reached, 29.2 percent having been achieved. In 1995 the CGT302 successfully recorded 33.1 percent at 1190°C of TIT with no trouble. We will introduce the current status of R&D of the CGT302 and its unique features in this paper.