Three-dimensional pulse tube simulations

In the design of pulse tube refrigerators, one-dimensional analytical models are usually used for calculating the influence of the system design parameters. The influence of the geometry is restricted to general system characteristics, e.g. the diameter only influences average velocity and properties such as flow resistance and heat exchange. Phenomena like acoustic streaming or turbulence are not present in these models. These phenomena are usually two- or three-dimensional, and cause additional losses in pulse tube performance. Therefore, in addition to the existing models, two- or three-dimensional computational flow dynamics calculations can be done to visualise and estimate the influence of these losses. In this paper, preliminary results - obtained with a commercially available CFD package - are presented.