Savonius turbine is a prominent drag based turbine used for harnessing wind or water power. It can be customized for run-off river stream locations having ultra-low head (<1 m) and low water velocities, for the turbine is self-starting and requires low starting torque. However, considering its low efficiency, an improved blade design of the turbine is needed to enhance its performance. If a Savonius turbine can generate power by utilizing lift force in addition to drag force then its performance can be improved; however any changes in its design need to be experimentally verified. In this paper, the performance of a combined lift and drag based modified Savonius water turbine is investigated in an open flow water channel at different water velocities between 0.3 m/s and 0.5 m/s, which are commonly found in a perennial river. The semi-circular blade design is modified by combining straight (drag profile) and airfoil (lift profile) blades. Detailed measurements show that maximum coefficient of power (0.268) is higher than some of the recently modified designs of Savonius water turbine. Further, correlation equations for power curves of the improved design for river stream application are also developed. The present work delineates the significance of modified Savonius turbine for efficient and cleaner production of water power.

Savonius涡轮机是一种出色的基于阻力的涡轮机，用于利用风能或水力。它可以针对具有超低水头（<1 m）和低水流速度的径流河水流位置进行定制，因为涡轮机是自启动的，并且需要低启动扭矩。但是，考虑到其低效率，需要改进涡轮的叶片设计以增强其性能。如果Savonius涡轮机可以通过利用除阻力以外的升力来发电，则可以提高其性能。但是，其设计中的任何更改都需要通过实验验证。在本文中，研究了一种结合了阻力和阻力的改进型Savonius水轮机的性能，该水轮机是在多年生河流中常见的水流速度介于0.3 m / s和0.5 m / s之间的开放水流通道中进行研究的。半圆形叶片的设计是通过组合直叶片（阻力型）和翼型（升力型）叶片而修改的。详细的测量结果显示，最大功率系数（0.268）高于Savonius水轮机的某些最新修改设计。此外，还开发了用于河流的改进设计的功率曲线的相关方程。本工作描述了改进的Savonius涡轮机对于高效，清洁地生产水力发电的重要性。还开发了改进的河流应用设计功率曲线的相关方程。本工作描述了改进的Savonius涡轮机对于高效，清洁地生产水力发电的重要性。还开发了改进的河流应用设计功率曲线的相关方程。本工作描述了改进的Savonius涡轮机对于高效，清洁地生产水力发电的重要性。