Griffith's early ideas on turbomachinery aerodynamics

Abstract

This paper is intended to supplement a part of the paper by Mr. F. W. Armstrong on ‘The aero engine and its prospects—fifty years after Griffith’. It deals in more detail with Dr. A. A. Griffith's early ideas on the aerodynamic aspects of turbomachines.Even with reasonably optimistic use of materials and operating temperatures it was essential in 1926 that very high component efficiencies were obtained to make the gas turbine competitive with the piston engine on fuel consumption. Griffith believed that efficiencies of over 90% could be obtained for the compressor and turbine components, if the correct attention was given to the aerodynamic design of the blades. His 1926 report on ‘An aerodynamic theory of turbine design’ showed how such high efficiency designs should be carried out and gave appropriate formulae for the compressor and turbine efficiencies.