CREATION OF A WORKING MODEL OF A HYDROPOWER PLANT FOR TESTING HYDROPOWER EQUIPMENT AT THE DESIGN STAGE

Abstract

The work designs a working model of a small hydroelectric power station and calculates the technical characteristics of the hydroturbine and the hydroelectric power station as a whole. The electric power of the model of the station is 15 W, the water pressure is 0.7 m. The model consists of two cubic plastic tanks with a capacity of 0.04 m3 each, which are located one above the other. The distance between the tanks is 0.35 m. Water from the upper tank is supplied to the hydroturbine using a plastic pipeline with a diameter of 50 mm. This pipeline is laid in the form of a siphon, that is, one of its sections is located above the upper tank. Filling the siphon with water is manual, using three ball valves located on the pipeline (one is on top, the other two are on different branches of the water supply, but below the water level in the upper tank). The hydraulic unit is located between the two tanks, the axis of the hydroturbine is vertically arranged. The hydroturbine is a tubular propeller type, the impeller diameter is 41.8 mm, the number of blades on the impeller is 4. In the hydroturbine, the water flow makes a 90° turn. A suction pipe is used to drain water from the hydroturbine to the lower reservoir. A centrifugal circulation pump with an electric drive pumps water from the lower reservoir to the upper one. The calculation of the parameters and technical characteristics of the hydroturbine of the HPP model was performed based on the principle of geometric similarity. The T90 hydroturbine manufactured by «Minihydro» LLC (Kharkiv) was taken as the “standard”. The calculation results are as follows: water flow rate – 0.003 m3/s, shaft rotation speed – 3119 rpm, mechanical power – 23 W. The state of readiness of the operating HPP model is 90%. In case of full readiness (100%), it will be used to perform experiments. The purpose of the experiments is to verify technical solutions and theoretical developments aimed at increasing the energy efficiency of tubular propeller hydroturbines. We are striving to improve the turbine impeller and the parts of the turbine housing close to it. We believe that this will result in the efficiency of turbines with impellers of even small diameters (from 250 mm to 1200 mm) being at least 90%.