A method for creating a pressure gradient by pulsed injection of air into a large vacuum chamber for laboratory simulation of plasma phenomena in a vertically nonuniform atmosphere is proposed. The dynamics of subsonic and transonic air flows at different background chamber pressures is studied. The feasibility of creating and detecting instantaneous pressure drops by more than two orders of magnitude on a scale of about one meter is shown. Features of the operation of the PMI-10-2 ionization gauge used for pressure measurements in a pulsed gas flow are discussed.