Improving Natural Ventilation Conditions on Semi-Outdoor and Indoor Levels in Warm–Humid Climates

Abstract

Building form and facade development for energy saving and generation are of great importance. Further development for natural ventilation purposes is also imperative as it is related to many issues that affect the quality of the living and working environment inside and around the buildings in outdoor and semi-outdoor spaces. In rapidly developing regions experiencing a warm and humid climate, like Saudi Arabia, mechanical cooling and ventilation are commonly used in residential and non-residential buildings. However, this was not the case in traditional structures, like the massive coral buildings of Jeddah, where cooling essentially depended on cross ventilation and heat storage in thermal mass. Further, the building forms in the traditional oriental city were optimized for natural ventilation on the macro-and micro-urban and room scales, respectively. Owing to the advancement in air-conditioning technology, conventional building design approaches tend to encourage sealed indoor spaces that rarely interact with the outdoor environment. Even in such harsh climates, during many months in a year, the outdoor temperature is remarkably low, allowing the utilization of natural ventilation within the rooms, as well as between building complexes and the surrounding spaces. This optimization process requires the integrated planning of many aspects, such as the facade, building form, as well as the intermediate threshold spaces between the indoor and outdoor spaces. Non-residential buildings in Saudi Arabia require a large amount of energy for operation. This is mainly due to the relatively high cooling demand caused by internal loads. A hybrid cooling system that incorporates mechanical and natural cooling and ventilation can be implemented for low-temperature days and nights. This paper presents a method for saving energy in a university faculty building, which is located in Jeddah. Models of the proposed solutions were analyzed using a computational fluid dynamics simulation tools, as well as the dynamic building simulation tool IDA-Indoor Climate and Energy (IDA-ICE) to assess user comfort and the level of reduction in energy demand.

Building Optimization through a Parametric Design Platform: Using Sensitivity Analysis to Improve a Radial-Based Algorithm Performance

“…This low variance and even constancy are also observed in Figure 10, showing that the temperature range for the window's operation resulted in a good NV performance (20-28 • C). On the other hand, setting a higher upper limit, bis 31 • C for instance, might also be acceptable and could be considered, as exposed in studies in hot and humid climates [96][97][98].…”

Using CFD to Evaluate Natural Ventilation through a 3D Parametric Modeling Approach

“…Furthermore, indoor air velocity (m/s) is another considered measure when assessing natural ventilation [62][63][64]. Increasing air movement has the potential to shift thermal acceptability to higher operative temperature values, as demonstrated in research in hot and humid climates [65][66][67]. The adaptative comfort standard ASHRAE 55 [68] also addresses this wind cooling effect and foresees an increase in the average airspeed depending on temperature, limited to 1.2 m/s.…”

Thermal Comfort in the Overhead Public Space in Hot and Humid Climates: A Study in Shenzhen

“…Currently, some scholars have conducted studies in the field of semi-outdoor thermal comfort. These studies have been carried out in different climatic conditions, such as tropical [14][15][16], subtropical [17,18], highland [19], Mediterranean [20], desert [21], and continental [22] climates. At the same time, they covered diverse space types, such as semi-outdoor learning spaces in colleges and universities [23], office buildings [24], cafeterias [25], stadiums [26], and bus shelters [27].…”