As hydraulic turbines utilize water, a renewable energy, to perform, considering various operating conditions of these turbines is of great importance. Due to the variation of electricity demand and also the performance head of the turbine, investigating turbine performance at different conditions would lead to a better understanding of the flow phenomenons inside them. One of the main factors decreasing water turbine's efficiency is the creation of a Rotating Vortex Rope (RVR) inside the draft tube at part load condition.