Caughley, AJTucker, AGschwendtner, MSellier, M2012-12-182012-12-1820122012AIP Conference Proceedings, vol.1434(57), pp.667 - 6740094-243X1551-7616https://hdl.handle.net/10292/4933Industrial Research Ltd has developed a unique diaphragm-based pressure wave generator technology for employment in pulse tube and Stirling cryocoolers. The system uses a pair of metal diaphragms to separate the clean cryocooler gas circuit from a conventionally lubricated mechanical driver, thus producing a clean pressure wave with a long-life drive. We have now extended the same diaphragm concept to support and seal the displacer in a free piston Stirling expander. The diaphragms allow displacer movement without rubbing or clearance gap seals, hence allowing for the development of costeffective long-life and efficient Stirling cryocoolers. Initial modeling, operating in conjunction with a 200 cc swept volume pressure wave generator, predicted in excess of 300 W cooling at 77 K with a Carnot efficiency of over 25%. A proof-of-concept prototype has achieved cryogenic temperatures. Details of the concept, modeling, and testing will be presented.Copyright © 2012 American Institute of Physics (API) (http://www.aip.org). The author(s), and in the case of a Work Made For Hire, as defined in the U.S. Copyright Act, 17 U.S.C. § 101, the employer named below, shall have the following rights (the ‘‘Author Rights’’): The right to use all or part of the Article, including the AIP-prepared version without revision or modification, on the author(s)’ web home page or employer’s website and to make copies of all or part of the Article for the author(s)’ and/or the employer’s use for lecture or classroom purposes - strictly for non commercial purposes only. If a fee is charged for any use, AIP permission must be obtainedStirlingCryocoolerDiaphragmFree pistonJournal ArticleOpenAccess10.1063/1.4706977