An improved displacement ventilation system for a machining plant

Guanqiong Wei, Bingqian Chen, Dayi Lai, Qingyan Chen

Research output: Journal article publicationJournal articleAcademic researchpeer-review

12 Citations (Scopus)


Machining plants are often highly polluted indoor environments with dense oil mist generated from metalworking fluids. Workers exposed to oil mist may suffer serious health problems. General ventilation is often used to dilute the oil mist level below the threshold of health risk. However, it is not easy to organize the flow for ventilating a large machining plant with hundreds of machines in order to effectively remove the oil mist. In order to develop an effective ventilation system, this study validated a computational fluid dynamics (CFD) program with the RNG k-ε model at a high Grashof number by using the measured air temperature and contaminant concentration in several locations in a high-ceiling lab with heat and pollutant sources. Next, the validated CFD program was used to develop an improved displacement ventilation system in which air is supplied from the lower parts of the support columns in the plant. With thermal plumes generated by machines and workers, the system formed unidirectional airflow that carried pollutants away from the work area of the factory. The system reduced the oil-mist concentration by more than 70% compared with existing ventilation system. In addition, suspended radiant heaters are recommended for supplemental heating in winter.

Original languageEnglish
Article number117419
JournalAtmospheric Environment
Publication statusPublished - 1 May 2020


  • CFD simulation
  • Experimental measurements
  • Indoor air quality
  • Thermal comfort

ASJC Scopus subject areas

  • Environmental Science(all)
  • Atmospheric Science

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