Performance Evaluation of an Undershot Water Wheel Turbine Using CFD

This research study simulates a water wheel using the finite volume method in Ansys fluent. A water wheel is a device that harvests energy from streams, open channels, and rivers. Water wheels were traditionally made of wood; however, the availability of new materials, specifically wrought iron, and the increasing demand for mechanical power through highly efficient systems during the industrial revolution period resulted in the rational design of water wheels with significantly improved performance and efficiency. Water wheel converts kinetic energy in water into rotational energy, which is then used to generate electric energy or as shaft power for a variety of applications. Water wheels have long been employed in mills, textile mills, and machine shops as a source of mechanical power. Water wheel conceptions and manufacturing processes evolved over time; by the end of the nineteenth century, technological breakthroughs in turbines had led to the discontinuation of water wheel development. As a consequence of revived interest in renewable energy and local and smart electricity production, water wheels are being re-considered as a clean and accessible alternative for micro power generation from water, particularly in regions with extremely low heads. Water wheels have various advantages over turbines, it is eco-friendly, easier to build, operate, and maintain, requiring less investment, and being more people friendly. However, the number of water wheel experiments has been very limited, and there is still a lot of ambiguity regarding their ideal operating conditions and performance characteristics. An undershot water wheel with 24 blades, uniformly distributed around the perimeter of a 12 ft diameter metal rim, placed in an open channel is employed for the simulation. The water wheel is an experimental facility that Uttarakhand Jal Vidyuth Nigam developed on a water channel that draws water from the Song River flowing close to Raipur, Dehradun, to lift water up to 90 feet for agricultural uses. The water wheel is attached to a reduction gearbox through a propeller shaft and to a multistage pump via a belt drive to transfer power from the water wheel to the pump. Multiphase flow is taken into account in the analysis since the water wheel is always in contact with both air and water. The purpose of this study is to determine the system torque, pressure, and velocity distribution acting on the water wheel blades, and changes in the flow regime upstream and downstream of the water wheel for a range of water flow rates. This study provides an opportunity to comprehend the elements influencing the water wheel’s capacity to extract power as well as its cut-in and cut-out speeds for safe operations. Additionally, the simulation data will serve as a baseline for future research to develop a robust water lifting method using a water wheel.