Design optimisation of internal shading device in multiple scenarios: Case study in Bandung, Indonesia

Abstract

In daylighting design for buildings, provision of solar shading device is required to ensure satisfaction of the visual comfort criteria in response to the sky condition. However, since real sky is constantly changing, the optimum state of the shading device would ideally be adaptive and dynamic, thus no single optimum solution can be expected. In this case, computational daylight simulation is a powerful tool for exploring the potential and solving the optimisation problem. This research therefore aims to demonstrate the use of computational daylight simulation to optimise internal shading device, regarding various daylight metrics in a real open-plan office with a west façade orientation in Bandung, Indonesia, using Rhinoceros and Grasshopper. To simulate multiple sky condition scenarios, optimisation was performed for four ranges of diffuse solar irradiance, i.e. 1–80 W/m2, 80–159 W/m2, 159–289 W/m2, and 289–541 W/m2, considering input variables of type of blinds (horizontal or vertical), slat angle, and blinds material specularity. The optimum solutions were obtained using Pareto frontiers that have been filtered with the constraints, which were determined separately for each scenario. Results show that the spatial daylight autonomy (sDA300/50%), annual sunlight exposure (ASE1000,250), and percentage of daylight glare probability (%DGP>0.21) can all satisfy the design criteria.