A High-Speed Dynamometer Developed to Measure a Small Gas Turbine Engine's Output

This paper provides a description of a newly developed dynamometer capable of measuring torque at speeds up to 90,000 rpm. The development which has been made enables the dynamometer to measure output of a small single shaft gas turbine engine without a speed reducing gear box. The unit consists of a high speed generator to absorb the power and a torque measuring device.

Since the generator is a key component of this dynamometer, a substantial portion of this paper is devoted to describing the configuration of the generator and the design considerations, as well as its performance.

The rotational speed of turbomachines is gradually being increased and will be accelerated further as ceramic materials are introduced. The subjects to be discussed here will, hopefully, be of some use when a torque measuring device for speeds over 100,000 rpm becomes necessary.