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In this study, the spatial distribution of the urban climate is evaluated and its impact on indoor overheating conditions is assessed. This was done by modelling the near-field climate of Ottawa and Montreal at 1 km resolution for the summer of 2018 during which an extreme heat event occurred causing nearly 100 deaths in this area. The climate data obtained from Weather Research Forecasting simulations were used for assessing the extent of overheating within a prototype model of a single-detached home using EnergyPlus. The overheating conditions were evaluated using the mean temperature, the number of hours with the temperature above 28°C, and the number of hours cooling from a base temperature of 28°C. A workflow for selecting representative locations within the city for building overheating assessments was established by considering five (5) different quantiles, including 0%, 5%, 50%, 95%, and 100%, of the three calculated overheating metrics over the urban and the rural area. The degree of indoor overheating in homes was quantified and differences in overheating of homes in urban and rural settings as well as those arising within different urban areas (intra-urban) were determined. The most significant intra-urban indoor mean temperature differences of buildings at different locations were 1.8°C for Montreal and 1.6°C for Ottawa. For the number of hours with a temperature above 28°C, the intra-urban difference can be up to 829 hours for both cities. It was also found that the overheating conditions between different locations may be affected by the external air temperature and other variables, such as the local wind speed, which greatly varied the natural ventilation air change rate of buildings. The overheating conditions in buildings of different locations were also compared by analyzing the time-series variation in temperature. It was determined that there always exists a difference between the duration and intensity of indoor overheating in single-family homes of different locations., CLIMA 2022 conference, 2022: CLIMA 2022 The 14th REHVA HVAC World Congress

Building models that can accurately predict hourly indoor air temperatures in free-running situations are key to understanding overheating conditions and the resilience of passive cooling strategies under a changing climate. To accurately predict indoor temperatures it is necessary to properly model pressure-driven infiltration and natural ventilation. This can be achieved by coupling a building thermal model to an airflow network model. In this paper, the development of coupled building thermal and airflow network models is described to calibrate building models using field measurements of indoor air temperature. Building models of three types of buildings were configured: long-term care building, primary school and multi-unit social housing. The building models were developed in Design BuilderTM and exported for use in an EnergyPlus simulation package. From information obtained from building surveys, site visits and architecture drawings, building parameters and operation schedules were collected. The unknown parameters, which included envelope thermal properties, shading devices, internal heat gains, envelope air leakage, window and door openings, were then calibrated based on measured values of indoor temperature. Reasonable ranges in value of the unknown parameters were first retrieved from applicable building construction practice documents and building energy standards. Two rounds of calibration were conducted through parametric simulations using the Monte-Carlo sampling method. A sensitivity analysis was also conducted for ranking the importance of all building parameters. The values for indoor air temperature as obtained through simulation were compared with measurements and the RMSE (root mean square error) was calculated for all values. The parameter value combinations corresponding to the minimum RMSE were adopted for the building models. The calibration process ended when the value for RMSE was, CLIMA 2022 conference, 2022: CLIMA 2022 The 14th REHVA HVAC World Congress

Although substantial advances have been made in investigating the storage and transport properties of shale gas in past decades, understanding of the flow characteristics and gas-bearing property in organic pores remains limited. In this paper, organic pores in the organic matter (OM) of the marine Longmaxi Formation are classified into six types based on the morphology and sizes of nanoscale pores. The structures of the six types of typical organic pores under high temperature and pressure are investigated based on the digital core compressibility method introduced in this paper. The results show that the pore-size distribution and connectivity of organic pores under high temperature and pressure are considerably different from those under conventional conditions. The apparent permeability of OM with different proportions of macropores, mesopores, and micropores are analyzed. The results demonstrate that the permeability of OM with Type 1 organic pores has the largest changes after compaction, whereas OM with Type 5 organic pores has a relatively smaller change. The regularities of the absolute adsorption amount and the free gas amount of OM with typical organic pores are also investigated. The absolute adsorption amount of OM decreases with the proportion of macropores, whereas the amount of free gas of OM increases. Finally, a chart of the absolute adsorption amount and the free gas amount of OM at different depths is given, which is helpful for estimating the gas-bearing capacity of OM and preliminary understanding the quality of a shale reservoir.

NRC-CU Seminar-Overheating and Mitigation of UHI, Sept. 29, 2021, NRC Construction Research Centre, Ottawa, Ontario

Fermented meat products have a long history in China. These products exhibit a characteristic unique flavor, compact meat quality, clear color, long shelf life and wide variety and are easy to transport. During the processing and storage of fermented meat products, microorganisms are present and exhibit diverse characteristics. Microorganisms can accelerate the degradation of proteins and fats to produce flavor compounds, inhibit the growth and reproduction of heterozygous bacteria, and reduce the content of chemical pollutants. This paper reviews the microbial diversity of Chinese ham, sausage, preserved meat, pressed salted duck, preserved fish and air-dried meat and provides analyses of the microbial compositions of various products. Due to the differences in raw materials, technology, auxiliary materials, and fermentation technology, the microbial species found in various fermented meat products in China are different. However, most fermented meat products in China are subjected to pickling and fermentation, so their microbial compositions also have similarities. Microorganisms in fermented meat products mainly include staphylococci, lactobacilli, micrococci, yeasts, and molds. The study of microbial diversity is of great significance for the formation of quality flavor and the safety control of fermented meat products, and it provides some theoretical reference for the study of fermented meat products in China.