Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-22T15:32:02.809Z Has data issue: false hasContentIssue false

The design and performance of high temperature turbines in turbofan engines

Published online by Cambridge University Press:  04 July 2016

G. L. Wilde*
Affiliation:
Rolls-Royce Ltd

Extract

It is understandable for fundamental cycle efficiency reasons that the technology level claimed by manufacturers in the development of gas turbines has tended to be judged by the declared maximum TET, but this is not any longer an adequate criterion. A better criterion would be the maximum TET at which it is possible to operate a turbine for a given value of the net turbine shaft efficiency after allowing for all the cooling losses without a penalty in the operating life of the turbine in service.

Figure 1 shows how the specific fuel consumption of turbofan engines varies with turbine entry temperature and overall pressure ratio for different levels of polytropic efficiency of all the components of −2%, +2%, +4% relative to datum. The importance of obtaining the highest possible component efficiencies rather than by further increasing TET and overall pressure ratio (which increase engine complexity and cost), is clearly brought out.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1977 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Wilde, G. L. and Pickerell, D. J. The Rolls-Royce Three-Shaft Turbofan Engine. AIAA Commercial Air craft Design and Operation Meeting Los Angeles, 1967.Google Scholar
2. Keen, J. M. S. Development of the Rolls-Royce RB 211 Turbofan for Airline Operation. Proceedings of the Society of Automative Engineers National Air Transport Meeting, New York, April 1970.Google Scholar
3. Eltis, E. M. and Wilde, G. L. The Rolls-Royce RB 211 Turbofan Engine. Proceedings of the Institution of Mechanical Engineers Vol 188 pp 549575 Paper 37/74.Google Scholar
4. Fullagar, K. P. L. The Design of Air Cooled Turbine Rotor Blades Symposium on the Design and Calculation of Constructions Subject to High Temperature, at the University of Delft, September 1973.Google Scholar