published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

Thesis (M.Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 174-175. / by Jamie Devol. / M.Arch.

A wooden, perforated, uniform cross-section duct was examined to determine the optimum levels of aperture ratio and fan speed with respect to uniformity of discharge. The optimum aperture ratio for the 8.54 m long duct was 1.0 with a uniformity coefficient of 90.28%. The fan speed had little effect on the uniformity of discharge. The friction factor was experimentally determined to be 0.048 for a non-perforated duct and this value was assumed to be the same for a perforated duct of similar construction. A kinetic energy correction factor was used to analyze the flow in the duct. Values for this correction factor were determined from experimental data. Values of the coefficient of discharge and the total duct energy were calculated. A mathematical model was proposed based on the conservation of momentum and the Bernoulli's equation. The model responded favourably and predicted the duct velocity nearly perfectly and slightly underestimated the total duct energy.

Air distribution ducts are used in the environmental control of livestock and poultry building as well as the conditioning of most agricultural produce. / In order to simplify the approach to the design of ventilation ducts, a mathematical equation has been derived to describe the average air velocity of a duct. / The primary objective of the research work was to test goodness of fit of an equation describing the average air velocity of perforated ventilation ducts, under balanced as well as unbalanced air distribution: $V = H sb{o}{X over L} + (V sb{L}-H sb{o}) {X sp2 over L sp2}$. / This equation was successfully tested using data measured from 14 ducts of constant cross-sectional area, built of wood or polyethylene with outlets of various shapes and aperture ratios. Results indicated that aperture ratio and distance along the duct are the two most significant factors influencing the average duct air velocity values, but material and outlet shape had little effect.

No description available.

No description available.

Systems Engineering was applied to Terraset, a school underground, heated and cooled via the sun. The Systems Engineering process (since it occurred after design) consisted of Needs Analysis, Functional Analysis, Test Requirements Analysis and System Life Cycle Cost Analysis. The school had never been Systems Engineered and the processes revealed a long list of requirements still lacking. The results of the thesis are applicable to a new design taking place at the Burke Center Elementary School. / M.S.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management