Quasistatic Efficiency of a Concentric ER Clutch

Abstract

An application of electrorheological (ER) fluid in ER clutch is considered. The clutch is embedded in a broader system with a driving machine on one side and a loading machine (brake) on the other. The quasistatic model of the system at a constant load and speed is described and solved in a dimensionless form.

Efficiency of ER clutch is determined as the ratio of the output and input powers and consecutively analyzed in the space of model parameters. A special sensitivity analysis for many thousands of combinations of parameters (in their possible ranges) is performed and statistically evaluated.

For some combinations of parameters and some arrangements of the system, efficiency can be greater than one due to additional energy originating from ER fluid. In such cases, more refined energy balance and definition of efficiency are needed.

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