Abstract: Side entering mixer apparatus has an impeller with an axis of rotation above and along the bottom of a tank in which the material (liquid or liquid suspension) to be mixed is disposed. In a discharge region in front of the impeller and in close proximity to the front of the impeller, there is disposed a flow straightening vane which removes substantially any radial component of flow. By removal of the radial flow component, helical flows which interact in the discharge region and cause pulsation of flow into the inlet region (between the rear surface of the impeller and the side wall of the tank from which it projects) are substantially eliminated and potentially catastrophic stress-induced failures in the side entering mixer and its seals are avoided.