The design of the Korea Air Force Academy subsonic wind tunnel

Abstract

A multipurpose subsonic wind tunnel facility has been designed for the Korea Air Force Academy in South Korea, and construction of this facility is nearing completion. This wind tunnel will be used in development of aircraft and ground vehicles as well as for basic studies in aeronautical engineering. The facility includes the wind tunnel and a building complex with offices, workshops, and test hall. The main test section dimensions are 2.45 m high, 3.5 m wide and 8.7 m long. Velocity ranges from 5 to 92 m/s with a fan power of 2,000 kW. High flow quality is achieved, with turbulence intensity designed to be below 0.05%rms (u'/U) and 0.1%rms (v'/U, w'/U). How angularity is designed to be less than +.0.1 deg. The wind tunnel has interchangeable test sections, several model support systems, a variety of instrumentation systems, and a probe traverse system. The external balance can be elevated to provide high accuracy for the various model types and to accommodate model/test section exchanges. The test facility systems and the building are integrated to provide excellent model handling and testing productivity. *Cheong-Ju, South Korea t Tullahoma, Tennessee 37388 Copyright * 1998 by Sverdrup Technology, Inc. Published by American Institute of Aeronautics and Astronautics, Inc., with permission. INTRODUCTION The government of the Republic of Korea and Korean industry are committed to establishing the capability for future aircraft development in Korea. The scope of this capability includes both military and civil systems. To meet this commitment, wind tunnels of sufficient size and capability are required. Several projects are now underway to support this effort. One of them, a subsonic wind tunnel undertaken by the Republic of Korea Air Force Academy (KAFA), is the subject of this paper. KAFA selected Sverdrup Technology, Lie. as the turnkey supplier of the subsonic wind tunnel, including preliminary and final design and construction services. Final design work has been completed and is covered in the present paper. Construction/installation and commissioning/calibration phases will be completed in 1998, and the results of that work will be presented in a future paper. FACILITY REQUIREMENTS During initial facility planning studies, KAFA configured the Subsonic Wind Tunnel as a closedcircuittype with interchangeable, atmospheric-pressure test sections. To support the Republic of Korea's commitment to aircraft and ground vehicle systems, the main testing activities planned to be conducted in the facility are: • Configuration optimization of aircraft • Development of high hit devices • Wing/body integration American Institute of Aeronautics and Astronautics Copyright© 1997, American Institute of Aeronautics and Astronautics, Inc. • Ground passenger vehicle aerodynamics • Building aerodynamics • Full aircraft component integration • Rotor aerodynamics • Helicopter aerodynamics Facility design requirements were established based on these testing activities. The requirements for test-type, test section size, performance, and flow quality are summarized in Tables 1 and 2. Compared to other mediumand large-size subsonic facilities, the KAFA facility's performance and flow quality requirements are state-of-the-art, and they are appropriate for advanced experimental education programs and aircraft development programs.