ORIFICE PULSE TUBE WITH VARIABLE PHASE SHIFT

摘要

An orifice pulse tube refrigerator (PTR) having a pulse tube (30) and a reservoir (28) with a compliance value C is provided with a variable acoustic impedance connecting the pulse tube (10) and the reservoir (28). The variable acoustic impedance includes two or more variable impedances, where may be a variable inertance (32) and valves (13) forming variable resistive members, wherein the resulting acoustic impedance has a phase angle that is variable for improved cooling efficiency. The inertance (32) may also be variable to further provide for varying the phase angle. In another improvement, an acoustic transmission line (34) connects the pulse tube and a driver unit for returning power from the pulse tube (10) to the driver to further increase the PTR operating efficiency.