Bending of bilayers with general initial shapes

Silas Alben

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arXiv · 1110.1007

Bending of bilayers with general initial shapes

Silas Alben

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Abstract

We present a simple discrete formula for the elastic energy of a bilayer. The formula is convenient for rapidly computing equilibrium configurations of actuated bilayers of general initial shapes. We use maps of principal curvatures and minimum-curvature direction fields to analyze configurations. We find good agreement between the computations and an approximate analytical solution for the case of a rectangular bilayer. For more general shapes (simple polyiamonds), we find a range of typical bending behaviors: overall bending directions along longest and shortest dimensions, inward bending at corners, curvature intensification near boundaries, and conical bending and partitioned bending zones in some cases.

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Silas Alben. 2011-10-05. Bending of bilayers with general initial shapes. https://arxiv.org/abs/1110.1007

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