Thermodynamic optimization of the turbofan cycle

Abstract

Purpose

To develop and find the effect of combination of four cycle design variables that minimizes the specific fuel consumption (sfc) of a turbofan engine.

Design/methodology/approach

After choosing the four variables, namely bypass ratio (B), fan pressure ratio, overall pressure ratio, and turbine inlet temperature (T₀₄), first the sfc was minimized without a minimum thrust constraint. Then, a minimum specific thrust constraint was introduced.

Findings

The unconstrained‐specific thrust is a two‐dimensional optimization problem, whereas the specific thrust constrained problem was found to be a three‐dimensional one.

Research limitations/implications

The variables B and ï are limiting factors to further improvement, as set by their maximum practical values, whereas the other two variables are to be optimized.

Practical implications

A very useful work, in which numerical optimization program was developed, for a turbofan cycle and could be extended to other cycles.

Originality/value

This paper offers a great help to those intending to optimize certain cycles with a number of variables.

Citation

Najjar, Y.S.H. and Al‐Sharif, S.F. (2006), "Thermodynamic optimization of the turbofan cycle", Aircraft Engineering and Aerospace Technology, Vol. 78 No. 6, pp. 467-480. https://doi.org/10.1108/00022660610707139