Experimental Study on the Parameters Affecting the Performance of Spiral Tube Pump and Numerical Study on Different Water Wheel Paddle Shapes for Locally Developed Stream Powered Spiral Pump System

Abstract

A stream powered spiral pump is a water pumping system that combines to old technologies; water wheel and spiral tube pump. It works based on cascaded manometer principle to pump a portion of water from a stream using the stream’s kinetic energy, harnessed by the water wheel. As a result it is commonly categorized under manometric pumps. Mainly under this category there are two types of pumps; coil pump and the spiral pump. Spiral pumps are considered to be a gift from God, because it uses renewable energy source, it has zero emission and operation cost, and it can be manufactured and maintained by local craftsman using available materials. But the problem is because of the emergence of conventional pump it was not well studied so the understanding on this tech was limited. Therefore, this research project’s general objective was to conduct an experimental study on the effect of important parameters on the performance of locally developed spiral pump system so that it can be readily design and applied for local irrigation work. In achieving this specific objectives the study were: to conduct a study on paddle shape of water to select the better; to conduct experimental study on the effect of submergence ratio, rotational speed, outer diameter and number of turns of the spiral tube pump; to compare the performance of coil pump and spiral pump; to optimize the parameters of the spiral pump system; and to clearly describe the design procedure of a spiral pump so that it can be readily developed. The study on paddle shape of the conducted numerically using SolidWorks flow simulation. The experimental study on the important parameters was conducted on Jimma Kito River. The comparison of the spiral and coil pump was done using analytical approach. Also the important parameters levels was optimized using Taguchi method. Finally understanding limitation was solved and then seven step design procedure was developed and stated clearly. Accordingly 22.50 slanted curved shape paddle found to be high velocity yielding for the spiral pump. Regarding to the important parameters submergence ratio and wheel speed mainly affects the pump discharge while the number of spiral turns mainly affects the head, and the outer diameter affects both. Also the coil pump will be better for the need of higher discharge and the spiral pump will give higher head for the same number of coils. Finally the important levels was given as factors for Taguchi method optimization using Minitab software, and pump running by 35 RPM, at 50% submergence, with 6 spiral turns and 1.5m outer diameter found to be the optimum, yielding 21 liters of water per minute to 4.1 meter head.