In this paper, the authors investigated the various factors, which can affect the performance of a turbofan engine. For this, the various subunits of a turbofan engine like inlet duct, compressor, combustion chamber, liner, turbine, exhaust nozzle etc. are investigated to find its various reliability characteristics through Markov process and supplementary variable technique (SVT). The main adv...

The model developed in this work was used to investigate the potential that active noise control techniques have for reducing fan noise on an ultra high bypass (UHB) turbofan engine. Active noise control is expected to perform differently on a UHB turbofan engine than on a conventional turbofan engine since the short and wide inlet duct inherent to the UHB engine promotes radiation from evanesc...

The aim of this study is to optimize performance functions of turbofan engines considering the off-design model of turbofan engine as well as employing multi-objective genetic algorithm. The design variables including high-pressure compressor pressure ratio, low-pressure compressor pressure ratio, fan pressure ratio and bypass ratio are calculated in such a way that the corresponding functions ...

Aircraft noise is a complex topic which is projected to increase with the increasing number of aircraft and size of the engines. Turbine-powered aircraft produce sounds that are considered pollutants at certain decibel levels. Turbofan engines are inherently quieter than turbojet engines for a given level of thrust. The purpose of this research is to determine if current turbofan noise reductio...

An equation and numerical solution procedure for a steady-state aerodynamic analysis of a turbofan engine in the meridional plane is presented. An axisymmetric average of the three-dimensional uid ow equations within the engine is presented. The equations simultaneously represent the major engine components and include terms for blade forces, loss, combustor heat addition, blockage, bleeds and ...

This paper describes the use of a machine learning technique for anomaly detection and the SAS® Event Stream Processing engine to analyze streaming sensor data and determine when performance of a turbofan engine deviates from normal operating conditions. Turbofan engines are the most popular type of propulsion engines used by modern airliners due to their high thrust and good fuel efficiency (N...

A method of investigating the effects of high angle of attack (AOA) flight on turbofan engine performance is presented. The methodology involves combining a suite of diverse simulation tools. Three-dimensional, steady-state computational fluid dynamics (CFD) software is used to model the change in performance of a commercial aircraft-type inlet and fan geometry due to various levels of AOA. Par...

A unified robust multivariable approach to propulsion control design has recently been developed at National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC). The critical elements of this unified approach are 1) a robust H-infinity control synthesis formulation; 2) a simplified controller scheduling scheme; and 3) a new approach to the synthesis of integrator windup prot...