Fluidic devices, including blind vortex tubes, constant-rotation double diodes and constant-rotation double vortex tubes, are disclosed with which to construct pulse tube refrigerators, including ones having diode loops, constant-rotation double diodes, constant-rotation double vortex tubes, and asymmetrical diode stacks. Present orifice pulse tube refrigerators use an orifice connected at the warm end of the pulse tube to a reservoir. The orifice and reservoir serve to control flows at the warm end of the pulse tube so that they are not in phase with flows at the cold end. Present heat exchangers at the warm end suffer inefficiencies due to heat-regenerative effects caused by return flows through the orifice. The fluidic devices disclosed herein create dynamic replacement orifices for pulse tube refrigerators that also serve as efficient heat exchangers and supercoolers with minimal regenerative characteristics.