Heating ventilation and air conditioning systems account for over one-third of building energy usage, especially for public buildings, due to large indoor heat sources and high ventilation and thermal comfort requirements compared to residential buildings. Natural ventilation shows high application potential in public buildings because of its highly efficient ventilation effect and energy-saving potential for indoor heat dissipation. In this paper, a building design is proposed for a science museum with atrium-centered natural ventilation consideration. The floor layout, building orientation, and internal structure are optimized to make full use of natural ventilation for space cooling under local climatic conditions. The natural ventilation model is established through computational fluid dynamics (CFD) for airflow evaluation under indoor and outdoor pressure differences. The preliminary results show that such an atrium-centered architectural design could facilitate an average air exchange rate over 2 h⁻¹ via the natural ventilation effect. Moreover, indoor thermal environment simulation results indicate that the exhaust air temperature can be about 5 °C higher than the indoor air mean temperature during the daytime, resulting in about 41.2% air conditioning energy saving ratio due to the free cooling effect of natural ventilation. This work can provide guidance and references for natural ventilation optimization design in public buildings.

Indoor air quality (IAQ) has a significant impact on human health, as people spend 90% of their time in various indoor environments. Therefore, research on IAQ is extremely necessary. However, current research on traditional Qiang residences in western Sichuan mainly focuses on the indoor thermal environment and heritage protection, with relatively little attention paid to IAQ. This study investigates the IAQ of traditional Qiang residences in western Sichuan, which have open fire pits as the core of daily life, exploring the impact of passive renovation strategies on the indoor air quality. Using simulation methods, this study employs passive strategies, such as increasing the size of windward windows, changing ventilation methods, relocating the fire pit, and enlarging interior partition openings, to improve and optimize the IAQ through natural ventilation. The results show that when the windward window sizes are 0.8 m × 1.9 m and 0.7 m × 1.55 m, the reduction in the indoor CO₂ concentration is the greatest, with a maximum decrease of 0.024% at the 1.5 m plane. This paper proposes passive renovation strategies to improve the indoor air quality of Qiang residences in western Sichuan. These strategies effectively enhance the indoor air quality of Qiang residences and address the research gap on indoor air quality in regional Qiang residences in western Sichuan. The insights and methods presented contribute to the improvement of the indoor air quality in traditional buildings and support the sustainable development of traditional architecture.

The optimization of ventilation strategies in high-ceiling theater stage spaces is crucial for improving thermal comfort and energy efficiency. This study addresses the challenge of uneven temperature distribution and airflow stagnation in stage environments by employing computational fluid dynamics (CFD) simulations to evaluate the effectiveness of different ventilation modes, including natural, mechanical, and hybrid systems. Six airflow organization scenarios were designed based on modifications to structural layout, equipment settings, and mechanical disturbances (e.g., fan integration). Key evaluation indicators such as temperature uniformity coefficient, airflow velocity, and exhaust efficiency were used to assess performance. The results show that a multi-dimensional optimization approach combining spatial adjustments and mechanical disturbances significantly reduced the average temperature from 26 °C to 23 °C and the temperature uniformity coefficient from 2.79 to 1.49. This study contributes a comprehensive design strategy for stage ventilation that improves comfort while minimizing energy consumption, offering practical implications for performance space design and HVAC system integration.

In the context of urban renewal, rooftop greening in old buildings plays a vital role in reducing carbon emissions and supporting carbon neutrality goals. This study evaluates the carbon capture capacity (TCO₂) and efficiency (ηCO₂) of rooftop greening under load constraints by developing standardised greening units and mathematical models to quantify CO₂ absorption and self-weight load. Rooftop carbon capture performance is assessed by comparing the quantified TCO₂ of each unit with the theoretical maximum and calculating overall ηCO₂. Three representative species—Hibiscus mutabilis, Prunus cerasifera ‘Atropurpurea’, and Gardenia jasminoides var. radicans—were examined. In single-planting mode, ηCO₂ was approximately 14% with no significant differences among groups, though TCO₂ varied considerably, ranging from 6061.32 g·d⁻¹ for Hibiscus mutabilis to 1515.52 g·d⁻¹ for Gardenia jasminoides var. radicans. In mixed planting, ηCO₂ showed greater fluctuation, with species combinations of similar TCO₂ enhancing efficiency. Findings demonstrate that rooftop greening can effectively expand urban green spaces, improve species diversity, and promote ecological balance, while providing a systematic evaluation framework for low-carbon renovation strategies in urban renewal.