Application Of Nnw-Flowstar Software in Transport Aircraft Simulation

Transport configuration usually use multi-segment swept wing with medium or high aspect ratio. Its flow includes wake flow, boundary layer interference, separated flow, wingtip vortex, transition and other complex flow phenomena, which poses a serious challenge on numerical simulation. Based on the self-developed National Numerical Wind Tunnel Project software named NNW-FlowStar and using unstructured hybrid grid technology, the validation research of simulation of transport aircraft is carried out. The NASA common research model (CRM) is the standard model of the 6th AIAA CFD drag prediction workshop. The effects of grid convergence, different turbulence models and quadratic constitutive relation correction are performed. The prediction accuracy of drag increment due to nacelle and pylon is analyzed. The results show that a nearly linear convergence property is achieved with grid refinement and the numerical method in this paper has second-order accuracy. The predicted results of drag at constant lift obtained by different turbulence models and drag increment due to nacelle and pylon agree well with the experimental data. The results obtained using SST turbulence model and quadratic constitutive relation correction are in good agreement with the experimental data. The reliability and effectiveness of the SST turbulence model and quadratic constitutive relation correction method for simulating the flow of transport configuration are validated.