Thermodynamic Analysis of Turbofan Engine

The present work deals with a detailed parametric thermodynamic analysis of all the possible configurations of turbofan engine (two and three spool with or without mixer and/ afterburner) employing transpiration cooling technique for turbine blade cooling. The study is focused on design point performance and is of general nature rather than an application specific parametric study. The analysis has been carried out by selecting/developing models for various components of engine. A computer program has been written which is capable of predicting engine dependent parameters (i.e. specific thrust, thrust specific fuel consumption, propulsive efficiency, efficiency of energy conversion and overall efficiency) at varying independent parameters at any flight condition and for any set of operating parameters. A set of multi-dimensional carpet plots predicting the effect of dependent in terms of independent parameters has been presented considering transpiration cooling for turbine blades and the temperature effect on specific heat of air/gas. Besides giving the comparative design point performance for a class of turbofan engine, these results could also be useful in assessing the relative benefits of extending technology to new engine configurations. Though, for a realistic mission application, the difference in performance at various thrust sizing conditions and at cruise conditions critical for fuel burn is a key characteristic in selecting the appropriate cycle, however this study could be useful in selecting in general the cycle configuration for a particular need with its optimum operating parameters.