PULSE TUBE EXPANDER HAVING A POROUS PLUG PHASE SHIFTER

摘要

A pulse tube expander (70) includes a regenerator (30), a pulse tube (42), a porous plug phase shifter (74), and a surge tank (60), in series gaseous communication with each other. The porous plug phase shifter (74) is made of a porous material such as a sintered mass or a packed solid bed of distinct, free-flowing bodies (84). The porous plug phase shifter (74) introduces a phase shift between the pressure wave and the mass flow rate in the pulse tube expander (70). The porous plug phase shifter (74) is resistant to clogging due to contaminication that may be present in the system.