Performance evaluation of a novel relay parallel push-pull ventilation system for long-distance pollution control

Abstract

The push-pull ventilation system, which uses air supply jets to enhance the transport of airflow, is an effective local ventilation method to control pollutants generated in industrial buildings. However, factors such as the increased scale of industrial plants and the restricted location of exhaust hoods have highlighted the need for long-distance pollutant control. In this paper, a novel relay parallel push-pull ventilation (RPPV) system was proposed to enhance the performance of long-distance local ventilation. Through experiments and numerical simulations, this system was evaluated and compared to the traditional parallel push-pull ventilation (PPV) system. Key performance metrics included the performance coefficient, airflow diffusion height, and energy-saving capability. The results indicated that the RPPV system is a very effective mode of long-distance transport. Firstly, the RPPV system exhibited superior airflow control over extended distances, enhancing airflow control by 30.5%. Importantly, it also managed to at least double the critical velocity, demonstrating the potential for longer control distances. Secondly, the RPPV system could achieve targeted airflow delivery, significantly reducing the diffusion height of supply airflows by up to 57%. Finally, the RPPV system consistently achieved the same airflow control as the PPV system, but with a smaller pull airflow rate, saving up to 40% of the pull airflow rate. These results present a promising solution to the problem of pollutant capture and airflow transport over long distances.