Due to the high fuel cost in recent years, more efficient flight vehicle configurations are urgently needed. Studies have shown remarkable performance improvements for the Blended-Wing-Body (BVVB) over conventional subsonic transport. Also, aircraft during taking-off and landing might face strong crosswind and heavy rain, and these effects may be even more detrimental for BWB due to its peculiar configuration. In this study, a 3-D BWB is first constructed and numerically validated, and heavy rain effects are simulated mainly through two-phase flow approach. Three crosswinds considered are 10m/s, 20m/s and 30m/s, and the resulting BWB's low speed stability derivative values under crosswind are different from typical transport, representing the intrinsic nature of BWB static unstable tendency. Also, the heavy rain influence to BWB is that lift decrease and drag increase at all angle of attack spectra, and liquid water content of 39g/m~3 is more detrimental than 25g/m~3, with maximum reduction of lift at 0 degree and maximum increase of drag at 6 degree angle of attack during taking-off and landing. The degradation in maximum lift to drag ratio could reach a stunning 10 to 15 percent at low angle of attack attitude.
展开▼
