  We present a hydrodynamic theory to describe a chiral electron system with a
Weyl spin-orbit interaction on a field-theoretic basis. Evaluating the momentum
flux density as a linear response to a driving electric field, we derive an
equation of motion for the orbital angular momentum. It is shown that the
chiral nature leads to a dynamic bulk angular momentum generation by inducing a
global torque as a response to the applied field. The steady state angular
momentum is calculated taking account of rotational viscosity.
