Abstract
Abstract
The article discusses some practical aspects of engineering
design associated with the use of Stirling cryocoolers in liquefiers
of hybrid cooling devices for HPGe detectors. A feature of hybrid
cooling devices is the presence of two modes: the recondensation
mode when the cryocooler is operating, and the power interruption
mode with a non-renewable LN
2 boil-off. Based on the Thermal
Networks Method, models for each mode are proposed, for analyzing
heat fluxes between standard components forming the liquefier
unit. The proposed models were validated by comparing calculated
parameters of the transition process between the two above-mentioned
operating modes with those obtained experimentally. It is shown that
the minimization of heat gain through the liquefier unit into Dewar
for both operating modes of the hybrid cooling device leads to
contradictory engineering design requirements. Preliminary
conclusions based on the thermal network models are confirmed
experimentally on a serial hybrid cooling device, produced by the
Baltic Scientific Instruments Company. This resulted in practical
recommendations on the choice of condenser position, which depended
on operating conditions of hybrid cooling device, for example as a
laboratory equipment or as a part of remote radiation monitoring
stations.