Ultra Long-Life Vibration Free Cryocooler

Research and development is proposed of a miniature low capacity cooler capable of reliable achieving and sustaining cryogenic temperatures for very long periods without maintenance and providing low capacity refrigeration to cryogenic sensors and coldelectronic systems. The cooler has no moving parts of any kind and very long life (10 - 20 years) is anticipated. The unit operates without noise and because there are no moving parts, mechanical vibration is eliminated. There are no lubricants or othercontaminants in the working fluids. Further the cryocooler is simple in form and may be made at low cost.The proposed cooler combines a thermoacoustic Stirling engine driving a pulse tube refrigerator. There are virtually no limits to the refrigerating capacity or to the temperature at which it may be designed to operate. Single stage pulse tuberefrigerators have achieved cryogenic temperatures of 40 K and multiple stage machines have achieved temperatures less than 4 K.The engineering design of a prototype unit will be competed in Phase I. The prototype will be made and evaluated experimentally in Phase II. The engineering design of a second generation prototype unit will be completed in Phase II.The refrigerator isintended to offer a long life cryocooler for great reliability of use on defense, and space exploration related satellites to cool infrared sensors and other imaging equipment as well as cold electronic systems both semiconducting and superconducting.Extensive terrestrial application of the refrigerator in a variety of capacities and at different tempeature levels is anticipated wherever low cost, reliable, refrigeration is required at all temperature levels, including the near-ambient temperaturesystems used for air conditioning and domestic refrigeration. The field of application is virtually unlimited a variety of military, civil, commercial, medical, scientific, educational and domestic use.