Evaluation of the local exergy destruction in the intake and fan of a turbofan engine

摘要

Modern air crafts and aviation industry are dominant consumers of fuel. The application of exergy analysis is powerful tool in the design and performance judgment of these systems. In this study, the local entropy generated and exergy destroyed in the intake and fan of a turbofan engine are investigated. The fan in concern has a highly twisted blade and is installed in the CF6-50 turbofan engine. The flow field is solved at the flight condition. fuerthermore, the local entropy generated, including thermal and viscous types, is computed from the predetermined flow field. Results show regions of entropy production at the boundaries as well as across the blade-to-blade passage. Moreover, remarkable entropy is generated at the wake region near the trailing edge, at the supersonic bubble attached to the leading edge, and across the blade-to-blade passage shock wave. Exergy destruction calculated computationally through the fan and the intake shows a good agreement with that calculated analytically. It is found that, under the cruise condition, the fan contributes by 1.95 MW of losses in useful work potential while this value for the intake is found to be neglected compared with the fan, 4.6 kW.