  We numerically study crossed Andreev reflection (CAR) in a topological
insulator nanowire T-junction where one lead is proximitized by a
superconductor. We perform realistic simulations based on the 3D BHZ model and
compare the results with those from an effective 2D surface model, whose
computational cost is much lower. Both approaches show that CAR should be
clearly observable in a wide parameter range, including perfect CAR in a
somewhat more restricted range. Furthermore, it can be controlled by a magnetic
field and is robust to disorder. Our effective 2D implementation allows to
model systems of micronsize, typical of experimental setups, but
computationally too heavy for 3D models.
