Abstract: An air separation device can include: a first compressor and a second compressor for compressing feed air; a first refrigerator and a second refrigerator for cooling the feed air; a pre-purification unit for pre-purifying the feed air; a flow rate measuring unit for measuring the flow rate of the feed air; a main heat exchanger for subjecting the feed air to heat exchange; a purification portion into which the feed air led out from the main heat exchanger is fed, and which separates and purifies product nitrogen and/or product oxygen from the feed air; and a compressor control unit for controlling the feed quantity of the feed air in accordance with an increase or decrease in the production quantity of product nitrogen and/or product oxygen.

Abstract: The intake noise reduction device is capable of suppressing hindrance to the airflow caused by deformation of a flow-regulating net portion and suppressing a reduction in the airflow amount. A linear portion having a mesh shape constituting a flow-regulating net portion 120 includes a circumferential linear portion 122 that extends circumferentially and, an radial width t1 in the upstream side, with respect to the airflow direction, of the circumferential linear portion 122 is larger than a radial width t2 in the downstream side thereof, and a radially outer surface 122A is constituted by a tapered surface that tapers toward the downstream side.