As the aviation industry is experiencing a rapid growth, the need to reduce aircraft fuel consumption is becoming more and more urgent, both for economic and environmental reasons. As turbines are the engine components with the strongest impact on consumption, it is important to acknowledge what losses characterize turbine flows and how they can be minimized, in order to improve turbine design and reduce CO2 emissions. This work aims at strengthening understanding of the losses generated by wakes mixing in downstream rows. The wake decay rate is mainly due to two mechanisms: viscous mixing, which results in loss, and a reversible process that varies the depth of the wakes.