1 GAS TURBINE TECHNOLOGY EVOLUTION- A DESIGNER’S PERSPECTIVE

During the past 50 years the aircraft gas turbine has evolved into the world’s most complex product which has made an astoundingly positive impact on mankind. Jet powered aircraft have provided the United States with unprecedented air power supremacy for defense and global reach to help promote worldwide peace and aid. Large turbofan powered transport and commercial aircraft have spanned the Globe, making the world much smaller while clean burning gas turbines are used worldwide for power generation. Lessons learned and design innovations developed for gas turbines have also been transitioned to rocket engines including the oxygen and hydrogen pumps for the space shuttle main engines. This presentation highlights key technologies created and developed by engineers and which have been responsible for the extraordinary evolution of state-of-art advances in gas turbine propulsion. In the Beginning The Americans got a late start in the development of the gas turbine engine because responsible leaders didn’t believe the gas generator cycle consisting of a compressor, combustor and turbine was practical. The reasoning was that after the power was extracted from the turbine to drive the compressor, there wouldn’t be enough residual energy in the exhaust gas for useful work. This reasoning was partially dispelled in the U.S. after the first flight of the Gloster aircraft in 1941 powered by the Whittle jet engine. Whittle was a visionary genius with excellent design engineering skills and great determination. His 1930 engine patent (Figure 1) shows a compressor with two axial stages followed by a centrifugal stage, an axial cannular combustor with fuel nozzles and a two stage axial turbine