Currently, COVID-19 is a global pandemic that scientists and engineers around the world are aiming to understand further through rigorous testing and observation. This paper aims to provide safe distance recommendations among individuals and minimize the spread of COVID-19, as well as examine the efficacy of face coverings as a tool to slow the spread of respiratory droplets. These studies are conducted using computational fluid dynamics analyses, where the infected person breathes, coughs, and sneezes at various distances and environmental wind conditions and while wearing a face-covering (mask or face shield). In cases where there were no wind conditions, the breathing and coughing simulations display 1–2 m physical distancing to be effective. However, when sneezing was introduced, the physical distancing recommendation of 2 m was deemed not effective; instead, a distance of 2.8 m and greater was found to be more effective in reducing the exposure to respiratory droplets. The evaluation of environmental wind conditions necessitated an increase in physical distancing measures in all cases. The case where breathing was measured with a gentle breeze resulted in a physical distancing recommendation of 1.1 m, while coughing caused a change from the previous recommendation of 2 m to a distance of 4.5 m or greater. Sneezing in the presence of a gentle breeze was deemed to be the most impactful, with a recommendation for physical distancing of 5.8 m or more. It was determined that face coverings can potentially provide protection to an uninfected person in static air conditions. However, the uninfected person's protection can be compromised even in gentle wind conditions.

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In this paper a multigeneration system is proposed, which utilizes geothermal energy and a lithium-bromide absorption cooling cycle. The proposed system is capable of providing electricity, heating, cooling, and domestic hot water to a small residential community in Vancouver, British Columbia, Canada. The performance of the system's heating and cooling capabilities were evaluated energetically and exergetically. A case study is presented by considering human occupancy loads and the impact of building material conditions on heating and cooling. System performance was investigated using parametric studies, where the operating conditions and ambient conditions were varied. Similar systems in the open literature were found to have an energetic and exergetic coefficient of performance of 0.8 and 0.3 for heating, while the proposed multigeneration system resulted in an energetic and exergetic coefficient of performance of 1.14 and 0.63 for heating, an increase of 30-52%. Additionally, the literature revealed that some systems resulted in an energy and exergy efficiency of 26.2% and 36.6%. The proposed multigeneration system achieved an energy and exergy efficiency of 31.86% and 63.33%, an improvement of 5.66-26.73%. The study was able to utilize the existing recommendations made by British Columbia to determine the necessary heating and cooling loads while also being able to successfully generate 4 useful outputs with a smaller footprint than those in the literature.

In this article, computational fluid dynamics is used to analyze the thermal performance of an electric vehicle charging system with lithium‐ion battery packs. In the analysis, the locations of an air conditioner, circulation fans, and safety barrier are varied to parametrically study the effectiveness of the thermal management system of the charging system. Temperature iso‐surfaces are generated and used to identify the regions within the charging system that are within normal working temperature ranges. The circulation fans greatly impact the effectiveness of the cooling system. The orientation of the fans also plays an important role in the distribution of temperatures in the battery packs. Furthermore, the individual battery improvement is quantified using the rack cooling index (RCI), where an RCI increase of up to 92.4% is reported when the circulation fans are activated. The results from this study demonstrate that a combination of circulation fans and an air conditioner can result in a simple and cost‐effective thermal management approach for a charging system, whereas an air conditioner alone cannot achieve the same cooling effectiveness.