Abstract: A design of a non-freezing vortex tube to operate with non-dried even wet inlet gas flow in a broad range of a vortex tube's cold fraction value, the non-freezing vortex tube includes a heat exchanger and a vortex tube comprising a slender tube, a diaphragm having a hole in the center thereof and closing one end of the slender tube, one or more tangential nozzles piercing the slender tube just inside the diaphragm and a throttle valve on the other end of the slender tube, the design comprising ways of connecting the non-freezing vortex tube to keep all diaphragm's surfaces above the point of freezing.