Masanori Yuri

Evolution and Future Trend of Large Frame Gas Turbines: A New 1600 Degree C, J Class Gas Turbine

MHI recently developed a 1600°C class J-type gas turbine, utilizing some of the technologies developed in the National Project to promote the development of component technology for the next generation 1700°C class gas turbine.This new frame is expected to achieve higher combined cycle efficiency and will contribute to reduce CO2 emissions.The target combined cycle efficiency of the J type gas turbine will be above 61.5% (gross, ISO standard condition, LHV) and the 1on1 combined cycle output will reach 460MW for 60Hz engine and 670MW for 50Hz engine.This new engine incorporates:1) A high pressure ratio compressor based on the advanced M501H compressor, which was verified during the M501H development in 1999 and 2001.2) Steam cooled combustor, which has accumulated extensive experience in the MHI G engine (> 1,356,000 actual operating hours).3) State-of-art turbine designs developed through the 1700°C gas turbine component technology development program in Japanese National Project for high temperature components.This paper discusses the technical features and the updated status of the J-type gas turbine, especially the operating condition of the J-type gas turbine in the MHI demonstration plant, T-Point.The trial operation of the first M501J gas turbine was started at T-point in February 2011 on schedule, and major milestones of the trial operation have been met. After the trial operation, the first commercial operation has taken place as scheduled under a predominantly Daily-Start-and-Stop (DSS) mode. Afterward, MHI performed the major inspection in October 2011 in order to check the mechanical condition, and confirmed that the hot parts and other parts were in sound condition.Copyright

Measurement and Analysis of an Efficient Turbine Rotor Pump Work Reduction System Incorporating Pre-Swirl Nozzles and a Free Vortex Pressure Augmentation Chamber

Measurements and analysis of an efficient turbine rotor pump work reduction system is presented. The system features; a “low” radius pre-swirl nozzle comprised of cascade vanes with a radial orientation, equal radius seals downstream of the nozzle, “jumper” tubes across the nozzle, and a free vortex chamber. A scaled experimental rig was utilized to measure and compare with predictions the following; rotor pump work, average tangential velocity exiting the nozzle, tangential velocity variation in the axial and radial direction, free vortex chamber static pressure rise, effect of relative velocity pressure losses, and effect of “pollution” by seal flow. The effort focused on measuring pump work reduction and the efficiency of the pressure augmentation system. In contrast to aero-engines where the main objective of pre-swirl is to reduce cooling air temperature to the blades, the main objective for this industrial gas turbine is to reduce pump work and increase output. An external pre-cooler is utilized to achieve the large cooling air temperature reduction required to maintain disk material limits. The analytical results and rig test data are presented and compared. The results substantiated the following: the level of reduced rotor pump work due to pre-swirl, the static pressure rise in the free vortex chamber, the effect of eliminating “pollution”, and relative velocity pressure losses. CFD analytical results are compared with the rig data.Copyright