Airflow modeling based on zonal method for natural ventilated double skin façade with Venetian blinds

•Zonal method coupled with airflow model is proposed to model natural ventilated DSF.•The simulated results of the model fit well with the experimental results.•The model has fast calculation speed for the natural ventilated DSF with blinds.•Increasing slat angle, cavity thickness, and height can decrease the DSF temperature.•Increasing the natural ventilated DSF height is benefit to improve thermal behavior. A zonal method based on the airflow model is developed to predict the temperature and airflow of the natural ventilated double skin facade (DSF) with Venetian blinds. Ventilation theories such as the Bernoulli equation, thermal pressure, and airflow network method are used to establish the airflow model. It is validated by the experimental data. The validation results show that the simulated results agree well with the experimental data. In addition, some factors that influence the temperature and airflow rate are discussed. It is found that the slat angle, air cavity thickness, and DSF height have different influences on the temperature and airflow rate of the natural ventilated DSFs with Venetian blinds. Meanwhile, changing the vent area has little influence on the thermal performance. This model is suitable for the dynamic modeling of natural ventilated DSFs with Venetian blinds, and renders with fast speed. A typical city in hot summer and cold zone (HSCW) zone in China - Changsha is taken to demonstrate the evaluation of the annual energy performance of the natural ventilated DSF in this model. The comparative results show that the annual energy demand of the natural ventilated DSF is close to the well thermally insulated fabric. The calculation time is about 51 min under Win 7 system on a standard laptop with 2.90 GHz dual-core CPU.