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This paper presents a new methodology for analytically evaluating the natural frequencies and mode shape of a turbomachinery blade in an environment where friction phenomenon occurs. The blades analyzed in this study are unshrouded and located in the high-pressure turbine found in turbofan engines, and in the compressor turbine found in turboprop engines. The goal of this method is to correctly predict the modal parameters of the blade in order to determine whether there will be any resonance in the running range of the turbomachinery, and to more accurately predict the stresses at the blade-disc interface. This study was performed using ANSYS® contact elements. After comparison, the analytical results were found to agree with the experimental results. A convergence study was also performed, and it was found that only the friction coefficient and the surface contact stiffness had a considerable effect on the natural frequencies and mode shape convergence.

A new aero-engine nose cone anti-icing system using a rotating heat pipe has been proposed to replace the current method of blowing hot compressor bleed air over the nose cone surface. Here, the heat is transferred from a hot source within the engine to the nose cone through a rotating heat pipe along the central fan shaft. A compact evaporator is used at the evaporator end due to space constraints in the engine. The system is modeled as a thermal resistance network where the thermo-fluid dynamics of each component determine the resistors. This paper reviews each of the component models and results, which show that the evaporator thermal resistance is one of the limiting factors for adequate transfer of heat for anti-icing.

The highly competitive aerospace industry demands the continuous improvement of aircraft propulsion engines and timely response to new and changing requirements for them. Turbofan engines are a relatively mature and sophisticated technology. Improving significantly the performance and weight by using conventional designs in mature technologies becomes costly, opposing the market needs for more affordable solutions. The introduction of the More Electric Gas Turbine Engine concept has been proposed as a way to attain significant improvements of the turbofan engine and aircraft in answer to the new and changing requirements. The More Electric Gas Turbine Engine concept as adapted to the specifics of small turbofans is explained. Implications and advantages of the concept for both engine and aircraft are considered. The proposed and the currently employed technologies are compared.

PW100 is the name given to the third family of P&WC engines. The PT6 started production in 1963, and has been developed to cover the power range from 500 to about 1200 horsepower. Forty five versions have been certified, to power 80 types of certificated aircraft. The JT15D turbofan engine started production in 1971, and the PW120 in 1984. That is, a new family has been founded roughly once per decade. PW100 is the designation of the whole family, and the last two digits in PW1xx will indicated the Take-off horsepower in hundreds. The PW115 and PW120 models were certified in December 1983, and differ only in the reduction of gear ratio and torque limit, being 1500 HP at 1300 RPM, and 2000 HP at 1200 RPM respectively. The PW124 is in development towards late 1985 production.