Vorticity Confinement and Advanced Rendering to Compute and Visualize Complex Flows
Yonghu Wenren, Jan Walter, Meng Fan, John S. Steinhoff · 44th AIAA Aerospace Sciences Meeting and Exhibit · 2006
This paper describes a method to compute and visualize rotorcraft brownout. An incompressible flow solver SAGE with Vorticity Confinement is used for the rapid, accurate prediction of rotorcraft flow fields in ground e ffect. The computations of flow over an entire helicopter configuration, including main rotor and tail rotor, are performed in a uniform Cartesian grid. The rotor blades are represented by very efficient lifting lines using a simple momentum source represe ntation together with Vorticity Confinement. An advanced rendering scheme is introduced. Preliminarily results show the realistic animation of the rotorcraft brownout that will give engineers a simulation tool with which they can develop landing descent tr ajectories and pilot training techniques. An incompressible code with Vorticity Confinement that is similar to SAGE is also used to compute flow over two impulsively started blunt bodies: A disk and an inflated parachute. Visualization of the vorticity mag nitude using advanced rendering is seen to be a very effective way to represent the flow field. The rendering using the package “Mental Ray ® ” from Mental Images is seen to be a very effective, efficient means to visualize the flows in a realistic manner, a nd at a computational cost comparable to the actual, very efficient, flow computation. Movie clips of computational results can be viewed at http://www.flowanalysis.com.