CFD Assisted Design Of Wind Tunnel-Circulating Water Channel

Wind Tunnel-Circulating Water Channel(CWC), an important teaching and research facilitie of Naval Architecture and Ocean Engineering National Laboratory in Shanghai Jiaotong University, is in the stage of detailed design currently. This facility can greatly enrich experimental research tools and enhance basic research in fluid dynamics and engineering R&D capabilities. The experimental system consists of low speed wind tunnel and circulating water channel. There are many difficulties in the design due to the originality.So further breakthroughs in design concept is urgently needed.In recent years, with the rapid growth of computational fluid dynamics(CFD) and computer technology, CFD techniques have been widely applied in many fields. In this paper, some problems in the design of Wind Tunnel-Circulating Water Channel is being preliminarily studied in this paper, using CFD commercial software FLUENT.In order to simulate multi-layer flow in the oceanic environment, separators is equipped in CWC. However,they may destroy the flow uniformity at the test section because of the retardation. The CWC in the cases of no separator,integrated separator and piecewise separator are simulated in this paper and results show that the form of piecewise separator is optimal. On the other side,As a basic laboratory facilities,high standards of horizontality are required. But installation error always exists and the ground is not so solid that the CWC's sedimentation seems to be inevitable after a few longer time. The inclination caused by installation error and uneven sedimentation will ruin the high quality of the flow field at the test section. CWCs at large angles are simulated. The results show that wave patterns changes a lot and air bubbles, which are bound to ruin the experiments, form. However, changes are not significant at very small angles of inclination. In addition, the bypass duct lead airflow to the test section during storm flow experiments.And velocity fell so rapidly that improving measures must be taken. Recovery and discharge of airflow is also discussed in this paper.Flow field of Wind Tunnel has the same high quality requirements. To enhance the uniformity of the flow at the test section, CFD is employed to optimize the wind tunnel's design after the verification with the experimental data.FLUENT and optimization software ISIGHT is combined to optimize the number of separators, dimension of stable segment and guide vanes.This research can provide reliable data for the design and construction of Wind Tunnel-Circulating Water Channel.