Session: 17-01: Poster Presentations

Paper Number: 170032

170032 - Evaluation of Adaptive Façade Design for Daylight Managements: Simulation and Validation Using Rhino-Grasshopper 

Abstract: 

Kinetic façade systems are a promising technology for reducing indoor cooling loads, offering additional benefits such as enhanced aesthetics through dynamic movement and improved daylight control via multi-angle adjustments or modulation of the window-to-wall ratio (WWR). Among these, adaptive façade systems are particularly effective in enhancing visual comfort by mitigating glare in response to changing outdoor environmental conditions. However, the design of such systems requires comprehensive consideration of building usage patterns, control strategies, and external influencing factors, including adjacent structures and ground reflectance. Accurate performance evaluation through simulation tools is also essential for effective implementation. This study investigates the impact of a kinetic façade on the daylighting performance of a medium-sized office building using Rhino-Grasshopper-based simulation workflows. The research process involved several key steps. First, a building model and kinetic façade system were developed in Rhino V8, with the façade integrated into the building using a package-type form for simulation. Second, solar and illuminance analysis logics were created using OpenStudio and Radiance, implemented via Ladybug in the Grasshopper environment. A daylighting simulation model was further developed using the Honeybee module based on the illuminance data generated. To validate the model, a comparative analysis was conducted against field-measured illuminance values. The coefficient of variation of the root mean square error (CV(RMSE)) was found to be under 5% on both clear and overcast days, confirming the model’s reliability. Subsequently, the daylighting performance of the façade was evaluated based on its operational rate, using five metrics aligned with LEED (Leadership in Energy and Environmental Design) criteria, including Daylight Factor (DF), Spatial Daylight Autonomy (SDA), Daylight Autonomy (DA), Annual Sunlight Exposure (ASE), and Useful Daylight Illuminance (UDI). Results showed that applying the kinetic façade to the window reduced ASE and UDI by approximately 25%, while SDA, DA, and DF decreased by more than 40%. These reductions fell short of LEED daylighting requirements. Additionally, performance improvements linked to variations in façade operation rates were marginal, with less than a 5% difference. This indicates that while kinetic façades are effective in glare control, they may significantly reduce available daylight when applied directly to windows. Despite this limitation, the package-type kinetic façade offers potential for integration with Building-Integrated Photovoltaics (BIPV), making it suitable for retrofit applications. Future research will focus on enhancing indoor environmental quality by adjusting façade transmittance and assessing the energy self-sufficiency potential through BIPV integration.

Presenting Author: Dongsu Kim Hanbat National University

Presenting Author Biography: DONGSUKIM received the B.S. and M.S. degrees in architectural engineering from Hanbat National University, Daejeon, South Korea (Republic of Korea), in 2011 and 2013, respectively, and the Ph.D. degree in mechanical engineering from Mississippi State University, MS, USA, in 2019. From 2019 to 2020, he was a postdoctoral associate researcher with the DOE Building Energy Codes Program, Pacific Northwest National Laboratory (PNNL), USA. He is currently an associate professor at the Department of Architectural Engineering, Hanbat National University. His research interests include building energy system modeling and simulation, HVAC control and optimization, and renewable energy applications for buildings.