Tunnel ventilation device

A tunnel ventilation device comprises a plurality of connecting frames distributed in the longitudinal direction of a tunnel, rectangular ventilation pipe sections communicated with one another are clamped between any two adjacent connecting frames, air inlet pipes are arranged on upper side plates of the ventilation pipe sections, and the air inlet pipes are communicated with air collecting pipes used for conveying air outside the tunnel. Air outside the tunnel enters the ventilation pipe section through the air inlet pipe; a plurality of air exhaust grooves are formed in a lower side plate of the ventilation pipe section, and air in the ventilation pipe section is introduced into the tunnel through the air exhaust grooves; a flow guide impeller is rotationally arranged in the ventilation pipe section and located between the air inlet pipe and the air exhaust groove, and the flow guide impeller can rotate along with introduction of air outside the tunnel and push the air in the ventilation pipe section to th