Modified Flow Regime for Pulse Tube Cryocooler

Pulse tubes are the cutting edge of regenerative cryocooler development. Their simplicity and ruggedness recommend pulse tubes over older technologies in a variety of military and civilian applications. In addition, since they have no moving parts in the cold head, pulse tube cryocoolers cause little or no vibration. That attribute is particularly important in computer chip manufacture, particularly as ever-smaller components make the chip-making process increasingly sensitive to vibration. A series of innovative improvements (the orifice, various bypass arrangements) have brought pulse tube performance into the range of Stirlings and Gifford-McMahon machines. Further improvement is possible. This proposal is for an innovative method of controlling flow and phasing flow in a pulse tube crycooler to enhance heat transfer and thus increase cooling power. There are strong experimental indications that this novel approach will substantially improve pulse tube performance.