Abstract: The measures of improving ventilation efficiency are summarized in terms of effective length of air flow, air flow tracks, impacts of different seasons on ventilation, wind speed, and arrangements of air ducts and fans. The design and optimization of ventilation in a complex underground oil-storage cavern is taken as an example. The importance of numerical simulation is especially emphasized. It could assess and optimize ventilation schemes, calculate the distribution of flow field, and analyze the effects of different ventilation passages. Experiences showed that numerical simulation method is an effective method of solving ventilation problems.

Key words: ventilation efficiency, construction of complex cavern, ventilation design, optimization of ventilation