Abstract
Water is one of the major sources of renewable energy and many hydropower plants are working across the world but they require specific values of head and flow rate for their operation and optimum results. There are many sites where limited head and flow rate is available but these resources cannot be exploited due to inefficient technologies. Gravitational vortex turbine (GVT) is a novel technology that is suitable for micro level power production where low head and flow rate is available. It consists of two main parts: vortex pool for vortex generation and turbine blades. This paper focuses on parametrical analysis of GVT to determine the geometrical characteristics which gives the best performance. These parameters would address; effect of velocity and symmetry of vortex with the ratio of upper diameter of funnel (D) to outlet diameter (d), effect of the angle of rectangular inlet passage on the vortex formation. It will also analyze flow in rectangular passage with constant cross section vs. converging cross section. All of these parameters have major impact on the velocity and symmetry of flow. Results show that outlet of the funnel should be 40% of the upper diameter while highest velocity was achieved when rectangular passage was at 60 degrees with pre-rotational plate at 30 degrees.