Study into next-generation supersonic powerplant meets objectives of reducing noise and emissions
Japan has completed a five-year, $120 million study of a next-generation engine for supersonic transport (SST) aircraft, generating new technologies that could be useful if a new SST is ever launched.
Ishikawajima-Harima Heavy Industries (IHI), which led the research and development project, says it met the objectives of reducing noise and emissions.
A reduction of 3dB in fan noise to the Stage 3 level was achieved through a new design of the outlet guide vane, featuring a special aerofoil profile. Jet noise was also reduced by 3dB by outfitting a special ejector mixer and outlet nozzle.
The nitrous oxide emission reduction target of 5g (0.176oz) per 1kg (2.2lb) fuel at cruise condition, and the carbon dioxide reduction target of 25% over current technology, were both met. IHI says new materials, leading to weight reduction and higher temperature resistance, and a special cooling scheme were introduced to achieve a 30% reduction in carbon dioxide.
Kawasaki and Mitsubishi also took part in the project, with General Electric, the Japanese Aerospace Exploration Agency (JAXA), Pratt & Whitney and Rolls-Royce.
Noise tests on a prototype turbine engine were conducted at P&W's Florida facility last August, followed by component rig testing for the emission reduction phase at R-R's Derby facility in March-May this year. Two engine tests for the carbon dioxide reduction phase were done in December 2002 and March 2004, using a high-temperature core engine (HTCE) prototype at IHI's Mizuho plant.
Incorporated on the HTCE is a new-generation single-crystal turbine blade using TMS-138 material, a ceramic matrix composites turbine shroud, an N18 powder metal disc, a titanium-aluminium shroud support and a metal-matrix composite fan disc. The prototypes will now be stored at JAXA and be used for general R&D.
BRENDAN SOBIE / TOKYO
Source: Flight International
