A computational investigation is conducted to study the patterns of airflow induced by corona discharge in the cross section of a circular tube. The secondary flow induced by corona wind in various flow passages has been the subject of numerous investigations. The flow patterns are often identified by multiple recirculation bubbles. Such flow patterns have also been anticipated for circular cross sections where the corona discharge is activated by an electrode situated at the center of the cross section. In this investigation, it is shown that, contrary to public perception, a symmetric corona discharge does not generate a secondary flow in circular cross sections. This investigation then proceeds to demonstrate that the flow responsible for thermal enhancements in circular tubes often reported in the published literature is induced only when there is a slight asymmetry in the position of the electrode. The present computations are performed in two parts. In part one, the electric field equations are solved using the method of characteristics. In part two, the flow equations are solved using a finite-volume method. It is shown that the method of characteristics effectively eliminates the dispersion errors observed in other numerical solutions. The present computations show that the flow in the eccentric configuration is characterized by a corona jet that is oriented along the eccentricity direction and two recirculation zones situated on either sides of the jet. In addition to the computational approach, a number of analytical solutions are presented and compared with the computational results.

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The goal of this research is to use Computational Fluid Dynamics (CFD) to numerically investigate the heat transfer associated with the waste heat released from using compost to assist the flow in a solar chimney. The novelty of the current research is the hybrid aspect of using a solar chimney in conjunction with compost waste heat to enhance the performance of the solar chimney. Additionally, the hybrid device will use photovoltaics stored on the roof of the solar chimney to generate electricity. Many CFD studies are available in the literature regarding the optimization of the solar chimney, which indicate that the power generation of the chimney is directly proportional to the height of the chimney, as well as the diameter of the base of the chimney. The new contribution of our present research will be in using CFD to quantify and match empirical data for the release of heat from a composting pile, which is the key piece of technology in converting the composting waste heat into usable renewable energy. Preliminary feasibility studies have been performed by the authors indicate the hybrid solar chimney concept to be viable, i.e. a 300 m tall tower will generate approximately 40 kW, which is in qualitative and quantitative agreement with other archived published studies.