Development and Testing of A Low Cost Linear Slot Impulse Turbine

Abstract

In this thesis, an impulse turbine with geometric characteristics aimed to have significantly lower manufacturing costs than other turbines of the similar scale was investigated. Experiments were performed to ascertain rotational speeds, torque, and power the turbine was capable. The turbine was of the impulse type with the channels between the buckets forming linear slots, milled with 0.125" (3.18 mm) bore. The thesis begins with a summary chronicling the development of the turbomachinery that led to the design of the turbine investigated. The characteristics of the turbine design are then discussed, emphasizing the geometric characteristics used to reduce the cost of manufacture. The thesis then covers the calculations used in the development of the dynamometer and the analysis. Details of the dynamometer structure are then expressed, beginning with a computer aided design model and then delving into the dynamometer built. Then the hardware that the dynamometer is comprised is discussed with details as to how each subassembly operates. The procedures followed to test the turbine in the dynamometer are then described. The results showed the turbine operated at speeds between 29,500 and 33,100 RPM. The average blade Mach numbers for that range of speeds was 0.287-0.322. The average torque measured during the tests ranged from 0.0451-0.0798 in*lbf (0.00510-0.00902 N*m). During the tests, the turbine was capable of producing 0.0230-0.0404 hp (17.2-30.1 W). The resulting efficiencies from the power produced ranged from 2.68% to 4.77%.