Clog Retard of a Vortex Throttle Joule-Thomson Cryocooler: Further Experimental Verification

Numerical analysis of clogging dynamics in micromachined Joule–Thomson coolers

“…6c). The influence of gas pressure on the water deposition rate agrees with the experimental findings of Maytal (2010).…”

“…Matching these electronics in size and cooling requirement, JT microcoolers provide cryogenic cooling power in the range of a few milliwatts to hundreds of milliwatts (Maytal and Pfotenhauer, 2013;Radebaugh, 2009). An important effect that limits the longterm performance of JT microcoolers is the deposition of impurities in the working fluid resulting in clogging of the microchannels (Lerou et al, 2007;Little, 1984;Maytal, 1998Maytal, , 2010Wade et al, 1988;Zhu et al, 2010). Wade et al (1988) observed the clogging formation in a straight glass JT expansion valve through a microscope and found that the ice formed initially near the low pressure side of the valve and then grew against the flow direction.…”

Temperature instability comparison of micro- and mesoscale Joule-Thomson cryocoolers employing mixed refrigerants

“…Thus, previous use of molecular sieve to trap residual amounts present in the mixture proved successful. Maytal [10] and Lerou [15] discussed clogging resulting from trace amounts of water in the refrigerant whether a mixture or pure fluid. These results emphasize need for drying and/or preconditioning of mixed refrigerants for micro-scale J-T coolers.…”

“…Longsworth [8], Luo [9], and Maytal [10] all make reference to fluctuations in temperature whether from flow fluctuations or intermittent clogging. Solutions have come by way of varying the J-T valve restriction during operation in some manner to alleviate the restriction to reestablish proper flow and/or remove clogs, which take place primarily at or near the J-T expansion valve.…”