A dynamic ventilation strategy for industrial buildings based on weight factors

Abstract

In industrial buildings, pollution sources are often multi-point and unstable. This study proposes a dynamic exhaust strategy (DES) that aims to balance energy utilization efficiency and system performance without the need for monitoring indoor environmental parameters. Firstly, the DES system only monitors the local pollutant concentration in each outlet to determine its “exhaust potential”. Weight factors are then assigned to adjust the total exhaust flowrate, achieving real-time dynamic weight allocation (DWA) and improving the system performance in removing pollutants. Secondly, the system monitors the total pollutants removal from all outlets to enable dynamic total exhaust flowrate adjustment (DTA) to reduce energy consumption. A stochastic release model of multiple pollution sources was established in a typical thermally polluted workshop, and numerical simulations were conducted to investigate the effects of factors such as the stochastic non-uniformity of sources release, frequency and range of dynamic parameter adjustments, and energy-saving potential of the DES system. The results indicate that the DES system demonstrates increased effectiveness in pollutants removal as the randomness of the sources release increases, with a 12 % improvement in capture efficiency η compared to the unregulated system. Additionally, by utilizing 80 % of the total exhaust flowrate to adjust it at a frequency of 5 s per time in the DWA process, the system can meet requirements for pollutants removal, performance, and stability. Furthermore, the co-regulation of the DWA and DTA processes can reduce energy consumption by 78 % while maintaining an 81 % capture efficiency compared to using the DWA alone.