One of the most effective ways of transmitting daylight into deep-plan buildings is to generate light-well for spaces away from the facade and window-less spaces. Among the limited methods of improving daylight efficiency in light-wells are reflectors that, as a surplus member of the wells, can aid in this improvement. A scrutiny of the light-well's configuration can give a correct perception of the performance of the well's walls with increasing the reflection coefficient to the designers in deciding where to install the openings, selecting the transmittance coefficient of glass, etc. In this paper, the main focus is designing and optimizing daylight assist devices on light-wells that can hierarchically reflect light from the sky to the bottom of the well (Device 1) and then emit into the desired space (Device 2). The research highlights that it is necessary to find a proper strategy for the devices regarding to the optimization process. The research design results in a comprehensive standard solution for different latitudes. The simulations were performed by Honeybee Plus version 0.0.06 and Honeybee-Ladybug version 0.0.69-0.0.66, which has the ability to simulate annual daylight performance at certain periods. Due to the maximum and minimum altitudes at any latitude, the study required time-criteria throughout the year. As a result, a cross-sectional study was carried out at two critical times: the first period (P1) and the second period (P2). Daylight metrics for analyzing configuration as well as evaluating devices are E'max, avg (illumination) and SHA (hour/m²). The DA'300 and DA'max2000 metrics were selected to measure daylight efficiency and glare risk, respectively, and the sDA is for the amount of floor area that uses enough daylight. Also, to better percept how to prepare improved-daylight at lower levels (especially for the performance of devices), the daylight autonomy has been reduced from 50% to 40% and a metric such as sDA't40 has been created.

The CFD simulation accuracy mostly depends on the appropriate setting of boundary conditions and numerical simulation parameters. This study shows the influence of two types of boundary condition settings on the CFD simulation results of Double-Skin Facade (DSF) for a specific problem. These two boundary settings are the constant temperature on the DSF surfaces called Boundary A, and Boundary B is defined via solar radiation using the Discrete Ordinate radiation Model (DOM). The paper verified both the numerical simulations using the experimental data. Comparing the numerical results of two types of boundaries with experimental data shows that both cases underestimated the values lower than 5.2 K and 0.1 m/s for the temperature and velocity respectively at the regarded measured points. Boundary A gives more accurate temperature prediction results, while Boundary B shows velocity magnitude closer to the measurements in the middle height of the cavity; the average temperature and velocity differences between the two boundary types are 0.6 K and 0.003 m/s respectively which are negligible. Finally, the selection of boundary conditions depends on study purposes, however, when the DSF is equipped with blinds and if there is not enough data in hand but the exact value of solar irradiation, using the Boundary B approach is suggested; it can provide reasonable results associated with multi-type of thermal boundary conditions at the same time. Furthermore, if the goal is to investigate the flow pattern in the DSF, Boundary B is argued to perform better than the constant temperature boundary condition.

Terraced apartments as a typology of the buildings are new approaches to meet energy conservation targets. This principle in the form of interactive spaces contributes to an incorporation of interior and exterior, daylight addition and exploitation of natural ventilation. This study mainly investigates the natural ventilation exploitation of a terraced apartment in the hot and humid region. One solid block and 4 porous apartments with different terrace depths (TD) are evaluated using computational fluid dynamics (CFD) analysis. The k–ε turbulence model was adapted to simulate airflow in and around a mid-rise building with 42 residential blocks. CFD analysis compares the effect of permeability in the form of terraces on wind behaviour and natural ventilation efficiency in a mid-rise building. Ventilation assessment parameters such as mean air velocity and mean age of air are measured to compare the natural ventilation performance. The simulation results clearly indicate that the implementation of permeability in the form of terraces can enhance building natural ventilation performance significantly. However, it is proved that some physical configurations such as terrace depth can influence this performance greatly. According to the results, increasing the terrace depth up to 1.2 meters will enhance the mean wind velocity 40%–88% inside the room, 10.61%–12.29% near the window and 63.44% on the openings. Velocity diagram follows a descending process after TD 1.2. The mean wind speed decreases to 25.53% inside the room, 15.09% inside terraces and 1.09% near the window. The average wind velocity on the openings is revealed to be 1.54 to 1.64 times larger in the porous models than the solid one. On the other hand, porous cases indicate lower values for the mean age of air compared to the solid model. This study provides proper guidelines to predict ventilation performance and to improve the design of naturally ventilated mid-rise buildings in hot and humid regions.