Page 27 - JCAU-7-3

Journal of Chinese
Architecture and Urbanism Natural ventilation in courtyard dwellings

achieving better airflow. This alignment allows for cross- elongated courtyards generally outperformed square
ventilation, a critical feature, especially during hot summer or circular ones in terms of ventilation efficiency. This
months. is attributed to their ability to channel wind flow more
Previous studies noted that the configuration of effectively, reducing resistance and enhancing cross-
courtyard doors and windows largely determines airflow ventilation throughout the building.
capacity. For instance, courtyard layouts featuring multiple In addition to size and shape, building height also plays
openings on opposite walls exhibited improved ventilation, a significant role. Surrounding buildings contribute to the
as air could circulate more easily through the space (Lu stack effect, in which hot air rises and exits through upper
et al., 2018). In contrast, courtyards with only one or two vents, while fresh, cooler air is drawn in at lower levels.
small openings created air stagnation zones, characterized Peng et al. (2019) documented this mechanism in Inner
by low air change rates and elevated indoor temperatures Mongolian courtyard houses, where taller courtyard walls
(Figure 5). These findings underscore the necessity of facilitated sufficient vertical air movement to alleviate
designing courtyards with an appropriate number and summer heat. A drawback of liver-shaped building design,
placement of openings to ensure effective integration of as explored in the results, is that it can obstruct airflow at
prevailing winds. lower levels due to wind shadowing—particularly when

4.2. Building geometry and ventilation efficiency the building height exceeds the courtyard size. Thus,
achieving optimal natural ventilation requires a balanced
Architectural features such as courtyard area, shape, and relationship among three key elements: building height,
the geometry of surrounding buildings influence natural courtyard size, and geometric configuration.
ventilation performance. Research examining the effects
of courtyard size on airflow showed that larger courtyards 4.3. CFDs simulations and empirical validation
facilitated better ventilation due to the greater availability Most of the reviewed studies used CFD simulations to
of free space. Kheiri (2018) found that rectangular or predict airflow patterns in courtyard-style buildings. These
simulations provided detailed insights into the effects
of various aspects of design, including window position
and size, building shape, and courtyard dimension,
on ventilation performance (Schulze & Eicker, 2013).
However, a common limitation across multiple studies was
the inadequate representation of microclimatic factors,
including terrain variability, vegetation morphology, and
building envelope materials. For example, train simulations
often assumed smooth wall surfaces and excluded transient
wind fluctuations, both of which significantly contribute to
the effectiveness of natural ventilation (Garcia et al., 2017).
Variants of CFD models demonstrated that improved
airflow and reduced hot air stagnation could be achieved
when courtyards had openings on more than one side.
Jomehzadeh et al. (2020) investigated airflow characteristics
in Inner Mongolia courtyard houses and discovered that
those oriented northwest were optimally ventilated. This
alignment supported effective cross-ventilation, enhanced
indoor air quality, and reduced reliance on mechanical
cooling systems. Simulations also revealed that buildings
with wind-catching protruding windows experienced
superior ventilation performance compared to those with
flush-mounted windows.
One of the CFD simulations performed in this study
focused on airflow within a typical Inner Mongolian
courtyard under different seasonal wind conditions.
Figure 5. Relationship between spatial arrangement, building geometry,
and ventilation efficiency in courtyard-style residential buildings Using ANSYS Fluent, the model analyzed and quantified
Source: Diagram by the authors. summer and winter velocity fields, pressure distributions,

Volume 7 Issue 3 (2025) 9 https://doi.org/10.36922/jcau.7226