Thesis (M.Eng. (Chemical Engineering)) -- University of Pretoria, 2007. / Includes bibliographical references (leaves 66-70)

Thesis (M.S.)--Cleveland State University, 2008. / Abstract. Title from PDF t.p. (viewed on July 9, 2008). Includes bibliographical references (p. 100-103). Available online via the OhioLINK ETD Center. Also available in print.

Thesis (M.S.)--Rochester Institute of Technology, 1995. / Typescript. Bibliography: leaves 72-74

Thesis (M.App.Sc.) - University of Queensland, 2004. / Includes bibliography.

Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 116-124). Also available on the World Wide Web.

Thesis (M.S.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: M. Ruhul Amin. Includes bibliographical references (leaves 121-125).

M.Ing. (Mechanical Engineering) / A reversible ground source heat pump, coupled to a municipality water reticulation system, is investigated as an alternative to conventional air source systems for space heating and cooling. The investigation was executed through the development of analytical models that were used for the design of a ground-coupled reversible heat pump and a conventional, also reversible air source system. The models were verified with experimental measurements. The results of the models and measurements indicate that ground source systems are a cost effective alternative.

D.Ing.

Cooling water systems are generally designed with a set of heat exchangers arranged in parallel. This arrangement results in higher cooling water flowrate and low cooling water return temperature thus reducing cooling tower efficiency. Previous research on cooling water systems has focused mainly on heat exchanger network thus excluding the interaction between heat exchanger network and the cooling towers. The studies completed on cooling water system in which the interaction between the cooling tower and the heat exchanger network was taken into consideration were limited to systems with single cooling tower. The main aim of this study was to develop a design methodology for synthesis and optimization of cooling water systems with multiple cooling towers. The design intends to debottleneck the cooling towers by reducing the circulating water flowrate. The study focuses mainly on cooling systems consisting of multiple cooling towers that supply a common set of heat exchangers. In this work the mathematical optimization technique was developed for optimization and synthesis of cooling water system. The heat exchanger network was synthesized using the mathematical optimization technique. This technique is based on superstructure in which all opportunities for cooling water reuse are explored. The cooling tower model was used to predict the thermal performance of the cooling towers while taking the thermal conditions of the associated heat exchanger network into account. The propose technique debotlleneck the cooling towers by decreasing the circulating water flowrate. This implies that a given set of cooling towers can manage an increased heat load. From the case studies, 22% decrease in circulating water flowrate was realized. The blowdown and makeup were also decreased by 7%. Furthermore, the cooling tower effectiveness was also improved by 4%. A decrease in the overall circulation water has an added benefit of decreasing the overall power consumption of the circulating pumps. There is also a potential for the reduction of makeup and blowdown water flowrate. / Dissertation (MEng)--University of Pretoria, 2011. / Chemical Engineering / unrestricted

An experiment was designed and carried out on the fundamental, but poorly understood problem of oscillating flow past a single, transverse, circular cylinder. This is an approximation of the flow about a single element in a matrix-type regenerator used in Stirling-cycle engines. The experimental rig was designed and built to allow tests to be carried out for the wide range of fluid flow parameters characteristic of various Stirling engines. The influence of these parameters on convective heat transfer rates was measured so the approximate effects of these same parameters on a Stirling engine regenerator could be determined. The main conclusion from the experiment was that average Nusselt numbers, based on test-cylinder diameter and subject to flow conditions similar to those found in Stirling engine regenerators, were 40 to 80% higher than those predicted by a steady flow correlation, for a given Reynolds number. This may be due to the high levels of turbulence generated near the test-cylinder. A secondary conclusion is that the compression and expansion of the working fluid due to a 90 degree phase angle difference between the motion of the pistons raises convective heat transfer rates from the test-cylinder substantially over the 180 degree phase angle, or "sloshing" motion case. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate