Multi-objective optimization study of compact kitchens based on coordinated ventilation strategy

To enhance thermal comfort in compact kitchens of multi-family residential units, This article proves that simple mechanical ventilation has limited effectiveness and proposes an optimization strategy that integrates mechanical air supply and natural ventilation. First, a high-accuracy (> 88%) kitchen simulation model is established by fitting the kitchen temperature variation function and eliminating non-essential factors, providing a reliable theoretical foundation for ventilation optimization. Based on this model, the range hood structure is further optimized to improve pollutant capture performance. The results indicate that when the smoke baffle angle is adjusted to 178°, the CO₂ concentration in the kitchen, except for the cooking area, remains below 1000 ppm, effectively improving air quality and reducing pollutant accumulation risk. However, under purely natural ventilation conditions, thermal comfort for cooking personnel remains suboptimal. To address this, an orthogonal experimental method is employed to investigate ventilation performance under different collaborative air supply conditions. Additionally, statistical methods are introduced to assign weights to key indicators, including CO₂ capture efficiency, weighted PMV(Predicted Mean Vote), air age, and ADPI(Air Distribution Performance Index), thereby constructing a comprehensive evaluation index S for quantifying kitchen thermal comfort. Under the final optimized collaborative air supply condition, the weighted PMV value for human thermal sensitivity is reduced by 92.23%, CO₂ capture efficiency is increased by 35.07%, ADPI is improved by 15%, and air age is optimized by 18.41%. Furthermore, compared to the high airflow ventilation scheme, the optimized scheme reduces annual energy consumption by 1.08 kWh under the assumption of 1-h daily operation. Experimentally validated, this study offers practical guidance for designing range hood baffles and energy-efficient ventilation in compact kitchens, and provides a useful index for evaluating indoor health and thermal comfort.