IGF::OT::IGF NUMERICAL SIMULATIONS OF A WIND TUNNEL FACILITY CAN PROVIDE IMPORTANT BENEFITS WHEN USED AS AN ADJUNCT TO EXPERIMENTAL TESTING. THE MOST OBVIOUS BENEFIT IS THE ABILITY TO UNDERSTAND MORE FULLY THE FLOW CHARACTERISTICS OF THE FACILITY, WHICH INCLUDE THE IDENTIFICATION OF ANY ANOMALIES SUCH AS FLOW NON-UNIFORMITY OR UNSTEADINESS DUE TO FLOW SEPARATIONS IN THE CIRCUIT OR DUE TO WAKES FROM VANES AND SUPPORT STRUCTURES. THE SIMULATIONS CAN HELP IDENTIFY AREAS WHERE UNEXPECTED LOSSES OCCUR. MORE IMPORTANT TO THE OPERATION AND SAFETY OF THE TUNNEL, THE SIMULATIONS CAN ALSO PROVIDE A BETTER ESTIMATE OF THE AERODYNAMIC LOADS ON THE TUNNEL STRUCTURE AND SUPPORT HARDWARE, AND PROVIDE BETTER DESIGNS OF FACILITY IMPROVEMENTS IN THE TUNNEL CIRCUIT. MOST WIND TUNNEL FACILITIES TODAY ARE DESIGNED USING EITHER EMPIRICAL METHODS OR IDEALIZED LUMPED-PARAMETER MODELS OF THE TUNNEL CIRCUIT. THEY ARE TYPICALLY SUPPORTED WITH TESTING OF SECTIONS OF THE CIRCUIT USING SMALL-SCALE MODELS WHEN THE COMPLEXITY OF A PARTICULAR PART OF THE CIRCUIT EXCEEDS THE EMPIRICAL MODELS. WHEN THE FACILITY BECOMES VERY COMPLEX OR REPRESENTS A NEW GENERATION OF TESTING CAPABILITIES THE NUMERICAL SIMULATIONS CAN PROVIDE BETTER AND SAFER DESIGNS. THE SIMULATIONS CAN ALSO PROVIDE DATA TO IMPROVE WALL CORRECTIONS FOR WIND TUNNEL MODELS THAT TAX THE EXISTING CAPABILITIES. THE NATIONAL TRANSONIC FACILITY (NTF) IS THE FIRST OF ITS KIND HIGH REYNOLDS NUMBER CRYOGENIC TRANSONIC WIND TUNNEL. THE NTF IS A FAN-DRIVEN, CLOSED CIRCUIT, CONTINUOUS-FLOW, AND PRESSURIZED WIND TUNNEL. IT IS ONE OF ONLY TWO HIGH REYNOLDS NUMBER TRANSONIC FACILITIES THAT CAN MATCH THE FULL FLIGHT REYNOLDS NUMBERS OF MANY OF TODAY S COMMERCIAL AIRCRAFT. IT CAN OPERATE IN DRY AIR AT WARM TEMPERATURES OR IN NITROGEN GAS FROM WARM TO CRYOGENIC TEMPERATURES. THE TEST SECTION IS 8.2 X 8.2 FT. IN CROSS SECTION AND 25 FT. IN LENGTH. THE TEST SECTION FLOOR AND CEILING ARE SLOTTED (6 PERCENT OPEN) AND THE SIDEWALLS ARE SOLID. THE NTF IS CAPABLE OF AN ABSOLUTE PRESSURE RANGE OF 15 PSI TO 125 PSI, A TEMPERATURE RANGE FROM -320 F TO 150 F, AN MACH NUMBER RANGE FROM 0.2 TO 1.2, AND A MAXIMUM REYNOLDS NUMBER OF 146X106 AT MACH 1. THIS PURPOSE OF THIS TASK IS TO DEVELOP A COMPUTATIONAL SIMULATION OF THE CONTRACTION, TESTSECTION WITH PLENUM AND MODEL SUPPORT SYSTEM, AND THE HIGH-SPEED DIFFUSER OF THE NTF UP TO BUT NOT INCLUDING TURN 1. THIS PROJECT WILL INCLUDE MULTIPLE PARTS. THE STARTING POINT FOR THIS WORK WILL BE THE GOVERNMENT SUPPLIED IGES CAD SURFACES DEVELOPED FROM THE LASER-BASED POINT-CLOUD SCANS OF THE FACILITY ALTHOUGH ADDITIONAL MODELING OF STRUCTURE MAY BE REQUIRED BEYOND WHAT WILL BE PROVIDED DEPENDING ON DETERMINED IMPACT. TO GET TO THIS POINT, WORKING WITH THE NASA RESEARCHERS AT THE NTF AND GEOLAB TO DEVELOP THE MODELED SURFACES USING A COMBINATION OF POINT-CLOUD DATA AND ARCHITECTURAL OR STRUCTURAL DRAWINGS MAY BE REQUIRED. THE NEXT STEP WILL BE TO DEVELOP AN UNSTRUCTURED GRID FOR THE NUMERICAL SIMULATIONS, WHICH WILL EXPLICITLY INCLUDE MODELING THE CONTRACTION, TEST SECTION, PLENUM, MODEL SUPPORT SECTION, AND HIGH-SPEED DIFFUSER OF THE NTF.