The development of energy recovery systems on existing water utility networks is a new challenge for increasing the sustainability of electricity generation mix. The concept of the new micro-turbine with counter rotating runners braces this goal by allowing the recovery of the energy which is spoiled in pressure reducing valves in many water supply networks. The hydraulic performances of the micro-turbine are evaluated through an analysis on the angular momentum balance applied to the investigated cross-sections of the machine. For this analysis, an experimental campaign involving 2D Laser Doppler Velocimetry (LDV) is performed to measure the velocity field of the flow at the inlet and outlet sections of the machine. Since the optical access to perform LDV measurements is blocked close to the hub of the runners, a further analysis on the mass balance and numerical simulations are performed to complete the velocity profiles and to evaluate the machine performance. The combination of numerical and experimental methods grants a full study on the operating condition of the micro-turbine and strengthens the results achieved. The results back up the best operating condition of the machine for different discharges and support further improvements of the runner blades shape.

现有水务网络上能量回收系统的开发是增加发电组合可持续性的新挑战。带有反向旋转流道的新型微型涡轮机的概念通过允许回收在许多供水网络中的减压阀中破坏的能量而达到了这一目标。通过分析应用于机器横截面的角动量平衡来评估微型涡轮机的水力性能。为了进行此分析，进行了涉及2D激光多普勒测速（LDV）的实验活动，以测量机器入口和出口处的流速场。由于执行LDV测量的光学通道在跑步者的轮毂附近被封锁，对质量平衡进行了进一步分析，并进行了数值模拟，以完成速度曲线并评估机器性能。数值和实验方法的结合为微型涡轮机的运行条件提供了充分的研究，并加强了所取得的成果。结果支持了机器在不同排放下的最佳运行状态，并支持进一步改善流道叶片的形状。