Civil Engineering and Architecture Vol. 12(3A), pp. 2436 - 2460
DOI: 10.13189/cea.2024.121336
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Improving Mixed-mode Ventilation Systems by Controlling Building Envelope Design for Office Spaces in Egypt

Yousra Rashad ^*, Mai Karram
Department of Architecture, Faculty of Fine Arts, Alexandria University, Egypt

ABSTRACT

Mixed-mode ventilation system (MMVS) is considered one of the building design strategies to reduce the cooling energy consumption of office buildings. In Egypt, as it represents the higher energy consumption rates in comparison to the consumed energy consumption for heating. The main objective of MMVS is to meet the indoor air quality and thermal comfort requirements of building occupants. This study aims to apply MMVS in Egyptian office buildings by merging natural ventilation (NV) with mechanical ventilation (MV) to take advantage of the two systems' features to achieve thermal comfort within the space. The air movement and energy performance simulation were used to study MMVS to achieve thermal comfort and energy savings. Firstly, an office building in Cairo, Egypt was selected as a case study to investigate the energy performance potential of MMVS. Secondly, measurements of air movement, air temperature, and relative humidity within the space were conducted at a specific year period to use the measurement data in the validation process. The validation revealed that the air velocity, air temperature (T), and relative humidity (RH) measurements were agreed satisfactorily with the building simulation results. Thirdly, a simulation for air movement and energy consumption was used to examine the air movement, energy performance, and thermal performance of the scenarios with different alternatives in the ventilation opening ratio (VOR%) and glazing types. The results indicated the possibility of increasing the thermal comfort hours by merging natural ventilation and applying MMVS in office buildings in Egypt. Changing the ventilation opening ratio (VOR%) has an effective impact on reducing cooling energy consumption by 6.47%, increasing NV hours up to 422 h, and decreasing HVAC hours by 893 h by ventilation opening ratio (VOR%) of 30%. Various glazing types were investigated and the findings indicated that the cooling energy savings can be increased to 12.21% by using clear double glass 6mm with a 6mm air gap in VOR% of 30%. Additionally, a noticeable difference in savings occurred by using tinted double glass 6mm with a 6mm air gap which achieved 28.05% in VOR% of 30%.

KEYWORDS
Mixed-mode Ventilation System, Energy Consumption, Energy Efficiency in Office Buildings, Thermal Comfort, Ventilation Opening Ratio, Glazing Types

Cite This Paper in IEEE or APA Citation Styles
(a). IEEE Format:
[1] Yousra Rashad , Mai Karram , "Improving Mixed-mode Ventilation Systems by Controlling Building Envelope Design for Office Spaces in Egypt," Civil Engineering and Architecture, Vol. 12, No. 3A, pp. 2436 - 2460, 2024. DOI: 10.13189/cea.2024.121336.

(b). APA Format:
Yousra Rashad , Mai Karram (2024). Improving Mixed-mode Ventilation Systems by Controlling Building Envelope Design for Office Spaces in Egypt. Civil Engineering and Architecture, 12(3A), 2436 - 2460. DOI: 10.13189/cea.2024.121336.