Abstract

A small, high subsonic, cryogenic wind tunnel was constructed at the National Defense Academy in 1985 as the fourth cryogenic wind tunnel in Japan. It was designed for testing high subsonic airfoils and other basic aerodynamic researches. The test section is 0.06 m in width and 0.3 m in height. The materials of the pressure shell are stainless cast steel for the contraction section and the high speed diffuser, and stainless steel for other sections. This tunnel has a centrifugal compressor and an external insulation system. These design features gave several problems at cryogenic operations. The improvement of the system and operating procedures have continued. Recently, the nitrogen gas exhaust system and cooldown procedures were modified to improve the cooldown characteristics of the tunnel. This modification resulted in about 18 % reduction of the total amount of liquid nitrogen consumed at cooldown. The preliminary evaluation and airfoil tests indicate that the present cryogenic tunnel may perform two-dimentional airfoil tests with even extremely low aspect ratio model.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.