| Popis: |
This paper presents and analyze the turbulent flow over a full configuration(body, wing, nacelle and pylon) aircraft, the AS28G, with a block structured NavierStokes solver on two parallel computers: IBM SP2 and Cray T3D. The results are compared with windtunnel tests and parallel efficiency are compared with two modern vector computers: NEC SX4 and Fujitsu VX. The experiment shows that a complete aircraft with a large Reynolds number (~ 10 7) can be correctly calculated within 2 days using a modern vector or parallel computer, with an error in lift of around 2% and in drag of about 4%. Parallel performance suffered from a bad load balance due to difficulties to predict the performances for the different blocks of the fine AS28G mesh. This makes the use of vector computers very competitive for these kind of large, complicated, 3D cases, with a single NEC SX4 processor corresponding to approximately 50 Cray T3D processors and 45 processors on the IBM SP2. The same figures for the Fujitsu VX were 34 and 32 respectively. |
