Parametric optimization of inertance type pulse tube cryocooler using computational fluid dynamics

The pulse tube cryocoolers are a big step up from the conventional cryocoolers given the absence of moving parts. The inertance modification to the pulse tube cryocooler further enhanced its reliability and efficiency. The inertance type pulse tube cryocooler has accumulated applications in various fields such as aerospace, bio-tech and military in recent times. The computational fluid dynamics approach chosen for the present work deals with the complex, confined and cyclic fluid flows encountered in the cryocooler. The analysis of the cryocooler for the zero-refrigeration load condition is carried out using the FLUENT package. A parametric optimization of the cryocooler is conducted by varying the pulse tube radius and reservoir volume, where an increase in cooling performance is observed. The operating parameters like porosity, frequency and pressure are also varied which emanates a direct correlation with the cooling rates. The study performed resulted in the pulse tube modification of 2.75 mm radius to be the optimal model with a lowest cold end temperature of 72 K for 200 s flow time. (author)