Small Vuilleumier Cooler

There has recently been much interest in spacecraft borne long lifetime mechanical coolers in Japan, because the cooling loads of IR detectors (IRCCD) for Earth observation instruments have become greater than the cooling capacity of radiant coolers. Therefore active development programs of several types of long lifetime mechanical coolers are in progress.The Vuilleumier cooler is one of the most feasible mechanical coolers for space craft system, because a cooler of this type has the potential advantages of long lifetime operation, small vibration, compactness and low weight. We have designed, built and successfully tested a feasibility model of the spacecraft borne Vuilleumier cooler for the first time in Japan.The major cooler performances are 1.8 watts of cooling capacity at 80 K, 52 K of no-load temperature, 28 minutes of cooldown time, and 130 watts of heater input power.