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Abstract Aircraft carriers are used today by the armed forces to transport aircraft around the world. In all cases, there are aerodynamic properties that can be studied. Computational Fluid Dynamic tool RotCFD was used to model the airflow over an aircraft carrier deck in three dimensions to understand the interactions between the air and the ship. The material presented here is based upon work supported by the National Science Foundation under Award No. EEC-0813570. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. Scott Beard, Ganesh Rajagopalan – Aerospace Engineering, Iowa State University Research Question How is the flowfield affected in the vicinity of the aircraft carrier deck? References Rajagopalan, Ganesh et al. “Experimental and Computational Simulation of a Model: Ship in a Wind Tunnel.” To be published. Results & Graphic/Charts Methods Acknowledgment I’d like to thank Dr. Ganesh Rajagopalan and his graduate students for working with me this summer and letting me use their office space and RotCFD, Stacy Renfro for being so supportive in the complexities of the task, and CBiRC for allowing me this research opportunity. Discussion • Velocity lower near ship deck and in wake of superstructure • Turbulence is most present near superstructure • Important to understand airflow around ship before rotorcraft • Air around moving ship will affect landed aircraft • Simulation should run for several seconds real-time • Finer or unstructured grids would better capture effects near ship • 3D Cartesian flow solver Rot3DC • Used to simulate airflow • Creates a Cartesian grid around objects • A fine grid of even interval was placed around the ship • A more course grid used in the surrounding areas • Grid gets finer closer to ship • Overall grid dimensions 247x118x122. • Ship modeled to be traveling 22.5 ft/sec for 1 second • Walls represent the effects of a wind tunnel X-direction velocities range from -1.92 ft/s in black to 32.6 ft/s in white, negative numbers going opposite of the free-stream flow. Flowfield Around an Aircraft Carrier Background In 1999, a rotorcraft was preparing to land on the deck of an aircraft carrier. As it approached, a V-22 Osprey already on the deck began to do an uncommanded lateral roll influenced by the landing craft. The investigation of the phenomenon was split into multiple parts. This research focuses on the airflow around the ship. Grid (247x118x122) Landing Spot 2 (127.5 ft from bow) Landing Spot 6 (442.5 ft from bow) Landing Spot 7 (547.5 ft from bow) Landing Spot 2 Landing Spot 4 Landing Spot 6 Landing Spot 7 Landing Spot 8 127.5 ft from bow 232.5 ft from bow 442.5 ft from bow 547.5 ft from bow 697.5 ft from bow Landing Spot 8 (697.5 ft from bow) Turbulence KE (0.00 to 0.328 m²/s²)
