Development and Testing of A Low Cost Linear Slot Impulse Turbine

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%

Wavelet analysis of ULF magnetospheric waves

Wavelet analysis is used to analyze magnetometer data and is compared to the traditional spectrogram technique, in particular, with respect to structured Pc 1--2 emissions. This results in the conclusion that the frequency modulation evident in Pearl pulsations is not continuous, but is comprised of waves localized in both time and space whose overall structure produces the stripe-like patterns. Utilizing information from the Multi-Resolution Analysis in conjunction with traditional spectrogram techniques this paper is the first to show clear signal power relationships between Pc 1--2 and Pc3 waves and also between Pc 1--2 and Pc 5 waves as detected on the ground. A technique in Wavelet analysis called signal decomposition will be used as a new technique for graphing wave power of all Pc categories simultaneously. This provides a way to compare ULF wave occurrences in order to determine if there is any relationship between them. The signal decomposition processing technique produces results directly contradicting the Bouncing Wave Packet model that has been traditionally invoked as the source of Pearl pulsation structures. A detailed comparison of the Continuous Wavelet Transform (CWT) with Multi-Resolution Analysis (MRA) shows the MRA to be a superior technique because the interpretation of the resulting analysis is not subject to a high degree of parameter variability characteristic of the CWT. This paper illustrates the usefulness of the MRA in studying the relationship between all classifications of Pc 1--2 waves with the simultaneous appearance of low frequency emissions and suggests areas for further study