An Effect of Spacing and Surface Finish on the Performance of Bladeless Turbine

Abstract

The Bladeless Turbine is a remarkable machine in terms of simplicity, robustness, efficiency, and applicability but little as known, even among today’s engineers, about how it works and how well it performs alongside conventional turbines. This paper presents effect of disc spacing and disc surface roughness on the performance of bladeless turbine. In this investigation, instead of blades, closely packed parallel discs are used. Resistance to fluid flow between the plates results in energy transfer to the shaft. High velocity water enters the disc pack through inlet nozzle path tangent to the outer edge of the discs. Convergent nozzle imparts high velocity water jet tangentially on disc thickness. Lower-energy water spirals toward the central exit port, adhesion, drag and impulse forces continue to convert kinetic energy to shaft rotational power. However, The Bladeless Turbine and a flexible test rig have been designed and manufactured, and experimental results are presented. An analysis of the performance and efficiency of the disc turbine is carried out. The design philosophy of the flexible test rig has been explained. Various complementary methods of measurement have been implemented and compared, and several operational experiences have been noted Experimental results for a 152mm diameter and 2mm thick discs of turbine are presented, which shows the variation of torque, output power, and efficiency as a function of angular speed. Measurements of static pressure are also taken at the inlet, Many design considerations and operational experiences are discussed. The effect of each parameter on the torque and power has been analyzed. It has been found that the spacing and surface finish has a significant effect on the power of the turbine. The maximum power obtained in this investigation was 33watts for 6discs and 0.5 mm spacing between discs with rough surface ( spiral Groove). The torque and power increases with decrease in spacing upto 0.5mm and increase in surface roughness value (Ra) 500 microns. From this investigation, it is clear that the developed bladeless turbine is working efficiently at 0.5mm spacing and 500 microns roughness disc surface.