Vortex shedding, such as the von Kármán vortex street, leads to higher mixing in the wake and unsteady forces on turbine airfoils. As a result, aerodynamic efficiency decreases and structural stress increases. The objective of the present work is to analyze the unsteadiness formed by vortex shedding at the trailing edge of a turbine vane and to manipulate/control this unsteadiness. The effects of steady injection through a tube at the trailing are studied. A detached-eddy simulation procedure, MBFLO2, is used to simulate the flow over and within the turbine vane section. It is found that the injection effectively reduces wake vortices and hence mixing in the wake as well as unsteady forces on the vane. Results show dependence on angular position of the tube as well as on the amount of injected flow.