A study of numerical simulation and available period of drag reduction for submerged body

• Main Authors: Sheng-Ta Hsu, 許生達
• Other Authors: Sheng-Ju Wu
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/81219616211477099727

碩士 === 國防大學中正理工學院 === 造船工程研究所 === 89 === For the drag reduction of submerged body, the simplest and cheap way is to coat the coating of the drag reduction on the surface of submerged body that the shape is already streamlined and the drag of friction just is dominant; it can improve performances of motion and lower the consumption of energy. It has been tested and verified that the drag of submerged body, which is coated by Kiss-Cote on the smooth coating of PU, has better behavior of the drag reduction in the turbulent boundary-layer flow. Using the approach of experiment, one has found the degradation of coating on the surface of submerged body in increasing time as a result of the action of viscous friction in the turbulent boundary layer; we devote our attention to investigate the effective period of drag reduction for the submerged body under water in this study. The drag test of model to a streamlined submerged body, in which one can measure the drag of model with regard to different flow speeds and estimate the effort of reduced drag, has been executed at the laboratory of horizontal circulating water channel of CCIT. In addition, the finite volume method in the computational fluid dynamics (CFD) is employed to make a situation of numerical water channel that is used to simulate the drag test of model, which is also proposed in this study. Combining commercial software ICEM with software CFX-F3D is employed as a solver; one expects that the result of experiment could compare with the numerical result due to the simulation of CFD to get in agreement.