A Smart Kinetic Double-Skin Window System for Enhancing Natural Ventilation in Sustainable Buildings

Abstract

This study presents the design and performance evaluation of a smart kinetic double-skin window system designed to enhance natural ventilation in buildings, especially those limited to single-sided airflow. The system dynamically adjusts external blade angles in response to real-time wind conditions, using environmental sensors and automated control to optimise airflow distribution and energy performance. Computational fluid dynamics (CFD) simulations were conducted for two blade configurations (7° and 15°) under varying wind speeds and directions. Results show that the 15° configuration enhances airflow reach and achieves up to 40% higher air change rates (ACH) compared to the 7°, making it more suitable for high-demand ventilation scenarios. In contrast, The 7° configuration produces lower but more uniform airflow, which is more appropriate for occupant comfort in residential or office environments. Detailed analysis of velocity fields, pressure distributions, and airflow paths confirms that the system effectively adapts to wind direction, maintaining balanced ventilation through integrated airflow channels. The simulations were validated against experimental data, achieving a Close correlation. While thermal and buoyancy effects were not included, future work will extend the model to hybrid ventilation scenarios. The proposed system demonstrates significant potential for sustainable ventilation applications in new and retrofitted building envelopes.

Keywords

Adaptive window systems / Natural ventilation / Computational fluid dynamics (CFD) / Smart building technologies / Energy-efficient façades / Double-skin façade design

Author Contributions

Conceptualization, M.V. and S.G.; Methodology, M.V.; Software, M.V.; Validation, M.V. and S.G.; Formal Analysis, M.V.; Investigation, M.V.; Resources, S.G.; Data Curation, S.G.; Writing—Original Draft Preparation, M.V.; Writing—Review & Editing, S.G.; Visualization, M.V.; Supervision, S.G.; Project Administration, S.G.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data supporting the findings of this study are openly available in Zenodo at: https://doi.org/10.5281/zenodo.15699893. The repository includes geometry files, mesh configurations, and CFD simulation results related to the performance evaluation of the smart kinetic double-skin window system.

Funding

This research received no external funding.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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