Design and Testing of Screw Turbines for Flat Flow with Uneven Blade Distances

It is an innovative thing to design turbines that are compatible with flat-flow water energy. The turbine that was chosen is a turbine screw model with a non-uniform blade slope. The turbine made with a stator consists of a collector pipe and a quick pipe as a nozzle and a screw-shaped rotor with varying blade spacing. The results of the design are two screw parallel with each consisting of five blades which are installed at 45°, 55°, 65°, 75° and 80° angles. The research methodology used is experimental through theoretical design and practical testing. Tests are carried out in uniform blade angles and compared with combination blade angles. The test results show that the turbine with a combination blade angle has a rotational speed lower than the maximum rotational speed (i.e., at 60° blade angle) but has better rotational stability against load changes. Turbines still have good efficiency even though the rotating speed drops to 60% due to loading.