  Films made from random nanowire arrays are an attractive choice for
electronics requiring flexible transparent conductive films. However, thus far
there has been no unified theory for predicting their electrical conductivity.
In particular, the effects of orientation distribution on network conductivity
remain poorly understood. We present a simplified analytical model for random
nanowire network electrical conductivity that is the first to accurately
capture the effects of arbitrary nanowire orientation distributions on
conductivity. Our model is an upper bound and converges to the true
conductivity as nanowire density grows. The model replaces Monte Carlo sampling
with an asymptotically faster computation and in practice can be computed much
more quickly than standard computational models. The success of our
approximation provides novel theoretical insight into how nanowire orientation
affects electrical conductivity, illuminating directions for future research.
