  Using experiments and numerical simulations, we demonstrate that the
curvature of microscale conduits allow programming of liquid crystal (LC)
flows. Focusing on a nematic LC flowing through U- and L-shaped channels of
rectangular cross-section, our results reveal that curved flow paths can
trigger gradients of flow-induced director field in the transverse direction.
The emergent director field feeds back into the flow field, ultimately leading
to LC flows controlled by the channel curvature. This curvature-mediated flow
control, identified by polarizing optical microscopy and supported by the
nematofluidic solutions, offers novel concepts in LC-based microfluidic valves
and throttles, wherein the throughput distribution is determined by the
Ericksen number and the variations in the local curvature. Finally, this work
highlights the role of deformation history on flow-induced director alignments,
when the viscous and elastic effects comparable in strength.
