Design of accurate integrated torque metering system for determining the fan efficiency of a turbofan engine
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Sergiy Yepifanov
Abstract
The known shaft torque helps with accurate engine control and diagnostics and is important for determining power and efficiency. For turbofan engines the known fan torque allows better estimating fan efficiency. Nevertheless, a component performance on a testbed differs from the same performance on the operating engine. Moreover, the testbeds are energy consuming. Therefore, testing of a component within the operating engine is the best way to know component performances. For turbofan testing, external torque meters are of little use, and a built-in meter is the unique option. This paper describes the design of a novel meter for a fan shaft torque in an existing turbofan engine. The paper first determines the torque measurement accuracy necessary for estimating fan efficiency. Then, a torque meter scheme based on shaft twisting is proposed. Finally, a 3D stress state meter model that determines a shaft twist angle for the given torque was developed.
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Research ethics: Not applicable.
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Informed consent: Not applicable.
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Author contributions: Sergiy Yepifanov: scientific leadership, paper reduction, correction of the manuscript. Konstiantyn Podgor’sky: research work, preparation of the draft of the text and figures. Igor Loboda: corresponding author, paper composition, English, correction of the text and figures.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: The authors state no conflict of interest.
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Research funding: None declared.
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Data availability: Not applicable.
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