Project Title:

A Vibrationless Long Life Pulse Tube Cryocooler

94-1	08.09	3800		

A Vibrationless Long Life Pulse Tube Cryocooler

Abstract:

The proposed innovation is a highly reliable lightweight pulse tube 
cryocooler featuring a metal diaphragm compressor driven by an efficient and 
inherently vibrationless liquid metal MHD motor. It addresses the stated 
subtopic requirements for lifetime and reliability improvement by reducing 
flexure bearing stress, by improving motor cooling, and by simplifying motor 
drive and control electronics. It eliminates vibration by axi-radial 
symmetric configuration of the diaphragm and motor fluid displacements. 
Objectives of the Phase I project are to demonstrate the concept of the 
critical component compressor in breadboard hardware, to benchmark the 
analytical design models, to produce a Phase II conceptual design, and to 
predict performance of a Phase II engineering model cryocooler system. The 
proposed effort includes analysis, design, and experimental proof-of-concept 
demonstration. Anticipated Phase I results include hardware validation of the 
concept and quantitative assessment of feasibility for spacecraft 
applications. Expected NASA applications for long life future robotic 
facilities are for cryogenic cooling of sensors, instruments, HTS 
electronics, and radiation baffles and shields. Benefits center on major 
improvements in reliability for both mechanicals and electronics and virtual 
elimination of vibration in positive displacement cryocoolers. 

Small cryocoolers using this technology may find use in cooling HTS 
components of cellular telephone base stations and other telecommunication 
systems, in portable infrared instrumentation such as optical pyrometers and 
absorption spectrometers, and in night vision systems for highway vehicles. 
The proposed innovation is also useful for heat pumps and refrigerators for 
both stationary and mobile applications. It will also allow the construction 
of very high reliability non-contaminating compressors for applications in 
pharmaceutical production and medical systems. 

Key Words

Creare Incorporated
Etna Road, P.O. Box 71
Hanover, NH 03755