Design Criteria and Configuration for Long-Life Aircraft Gas Turbines 670344

This paper presents an analysis of major life-limiting problems in military and commercial service experience. Design action and means to verify the solution have included engine and laboratory tests. The experience gained has led to the development of design criteria, most of which have a basis in analysis of flow models, rotor dynamics, wave mechanics, heat transfer, or stress fields. Design criteria, when adequately substantiated, become effective means of helping protect new designs from life-limiting problems possibly related to: coking of vent tubes, seals, and sump walls; materials joining; low-cycle fatigue, including thermal cyclic stresses; fretting and wear; bearing retention; blading; installation effects; and flexural vibration and fatigue of the thin walls of flow passages.