Outdoor air cleaning system

An outdoor air cleaning system comprising:

• a partition surrounding a purification space to isolate the purification space from an external space and having at least one opening connecting the purification space to the external space;
• an air purifying device configured to supply purified air to the purification space;
• a controller configured to control the air purifying device;
• a temperature adjusting device configured to form a temperature gradient between the purification space and the external space, and
• a blocking device including at least one flow device installed adjacent to the at least one opening,
• wherein the at least one flow device has a discharge port having an angle directed to the purification space such that the at least one flow device is configured to eject the purified air towards the purification space,
• wherein an openness level is about 10% or more and about 50% or less, and
• wherein the openness level is an area ratio of the at least one opening with respect to a total surface area of the partition surrounding the purification space.