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MacPhee, David W.

Publications and source records attributed to MacPhee, David W..

Alabama Industrial Assessment Center: Training Students and Sustaining Industry (Final Report)

The overarching goal of this project is to educate and train engineering students in energy management protocols. The centerpiece of the program is achieved by delivering direct energy-management assistance to manufacturers through industrial assessments and workshops. Additional facets are achieved through report writing, formal curricular coursework, and on-line/self-directed training. This program delivered significant workforce development in the area of energy management practices. Participants in the program received hands-on experience in real-world industrial energy usage and management practices. Additionally, the industrial manufacturers received benefit of collective energy management skills of the research team towards reducing energy consumption at their sites. These activities are beneficial to the public in two ways. First, the trained participants from the program will move out into the manufacturing sector and propagate the energy management expertise they gathered during the program. This is a long-term benefit that will pay back to society over many years. Second, the manufacturers that receive energy assistance under the program realize a direct and immediate increase in their energy efficiency.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Performance of Closed Loop Venturi Aspirated Aeration System: Experimental Study and Numerical Analysis with Discrete Bubble Model

In wastewater treatment plants, aeration plays a significant role as it encourages aerobic respiration of microbes, which are necessary to break down carbonaceous matter in the waste stream. This process can account for the majority of energy use in wastewater treatment plants. The aeration process is also necessary in odor control in lagoons and in the aquaculture industry. Generally, the aeration process is accomplished with compressors or blowers which can be of low efficiency due to ideal gas laws. This study introduces the idea of increasing aeration efficiency by looping water from a reservoir through a piping network which includes a venturi aspirator at its inlet. For this purpose, an experimental study has been conducted in a laboratory setup with a pump which pulls water from a tank, passes it through a Venturi aspirator and a helical piping network intended to increase bubble residence time, before depositing it back into the bulk fluid tank. This same process is modeled computationally, using a discrete bubble method (DBM), with good agreement with experiments. The overall purpose here is to determine the optimal configurations for standard aeration efficiency (SAE) and the standard oxygen transfer rate (SOTR). A parametric study has been implemented using the DBM based on different hydraulic and flow parameters. The model is also used to predict the SAE of a hypothetical aeration system. Results indicate that it is possible to achieve SAE values in the range of surface aerators or submersed jet aerators using the proposed aeration system with less complex components, thereby decreasing overall costs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗