Typescript (photocopy). / Digitized by Kansas Correctional Industries

The overall objective of this study was to evaluate the performance of selected furrow irrigation models for field conditions in south-east Australia. The other important aspects which were examined during this study include: developing a methodology for estimating of infiltrating characteristics, assessing the applicability of the Manning and other similar equations for flows in furrow irrigation, investigating the variation of shape factor during irrigation developing methodology for estimation of recession time and exploring the sensitivity of the models to the input parameters. Field experiments were conducted at Walla Park in northern N.S.W. and on two selected paddocks at the University Farm, Richmond, in western Sydney,Australia, over a period of three years. The validity of the assumption that the shape factor of advancing water front during furrow irrigation varies between 0.7 and 0.8 was investigated using field data collected from irrigation events monitored in the study. It was found that the average values of the shape factor varied from 0.96 to 1.80 at Walla Park site, from 0.56 to 0.80 at Field Services unit paddock site and from 0.78 to 0.84 at Horticulture Farm paddock site. The value of shape factor was affected by uniformity of furrow cross section along the length, the value and uniformity of furrow slope, furrow length and infiltration characteristics of soil. This means it is difficult to recommend a typical value for the shape factor for a given field situation.The performance of the models for prediction of advance and recession characteristics and runoff were evaluated using different indices of performance. In general, it was found that the Walker-HD and ZI model was the most satisfactory for the field conditions encountered in this study. This finding can provide a basis for initiating work on developing design criteria and management strategies for furrow irrigation in south-east Australia. / Doctor of Philosophy (PhD)

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 198-204). Also available on the World Wide Web.

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In the spring of 1998, a closed end gravity flow pipeline was installed in the Lethbridge Northern Irrigation District. The pipes ranged from 900 mm to 300 mm in diameter. / Manholes were placed at several locations along the pipeline and were used to install velocity meters and pressure transducers, which recorded data every second. Pressures and velocities during periods of steady state were used to calculate the head loss, Re and the Hazen-Williams friction factor, "C", along lengths of constant diameter. / The results were compared to the industry design standard of C = 150 (used for the design of rigid PVC pipe installations) and to the theoretical hydraulically smooth line developed from the Moody diagram and the Darcy-Weisbach equation. Since the maximum and minimum calculated values of C came in the 750 mm and 900 mm diameter pipes, respectively, and all other C values, including those from the 300 mm and 650 mm diameters, fell between these, pipe diameter was assumed not to be a variable. Therefore all the field data was averaged. The average value of Re for the range studied was 9.73 x 105 . The corresponding best-fit C value is 147.7, which is 6.0% lower than the derived theoretical maximum. Since the derived theoretical maximum is the ideal condition and the recorded data was slightly lower and therefore determined be a good representation of what can be expected in true field conditions.

The purposes of this thesis are to examine experimental results obtained with subsurface irrigation of maize in 1988, and to provide preliminary plans and an economic analysis for the subsurface irrigation of maize in Richelieu County, Quebec. A mean increase in maize yield of 3.7 % was observed in 1988 on experimental plots with subsurface irrigation at the Charbonneau farm. However, a review of results obtained at the same experimental site from 1982 to 1988 indicated that the mean increase in maize yield with subsurface irrigation was 29 %. / Plans for two possible water supply systems designed to provide 180 mm a year of irrigation water for the subsurface irrigation of 1,250 ha in Richelieu County were considered. An economic analysis indicates that subsurface irrigation using groundwater has the greatest net benefits with an internal rate of return of 22.92 % and benefit to cost ratios of 1.90, 1.72 and 1.56 for discount rates of 8 %, 10 % and 12 % respectively. However, much of the groundwater in this region is saline and its use for irrigation may need to be restricted. Subsurface Irrigation using surface water from the Yamaska River was also profitable with an internal rate of return of 17.31 % and benefit to cost ratios of 1.66, 1.46 and 1.30 for the same discount rates.

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Techn. Univ., Diss.--Braunschweig, 2004.

Thesis (M.S.)--University of Wisconsin, 1967. / Extension Repository Collection. Typescript (carbon copy). Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 84-85).