Study On Drag Reduction Characteristic And Drag Reduction Mechanism Of Bionic Jetting Surface

The problem of utilizing bionic surface to reduce the drag force when objects move in liquid has caught great attentions in drag reduction field. Some features which biology obtained from evolution play an important role in reducing drag fore and this has been accepted by researchers of this field. More comprehensive and in-depth studies on bionic drag reduction features are carried out at present. By imitating the jetting flow feature of shark gills with bionics principle, a bionic jetting surface drag reduction technology was brought forward in this article. Studies on the bionic jetting surface will further enrich the content of the drag reduction field and have values in the development of drag reduction theory. Simultaneity, using bionic jetting surface drag reduction technology has a broad prospect in the fields of above-water and under-water vehicle, pipelines and aeronautics. It also has significance in energy conservation and economic development.The international and domestic status of main drag reduction technologies was introduced and a bionic jetting surface model with round jetting outlet was established which imitate the shark gill's jetting flow feature, principle of bionics was utilized and the possibility of engineering application was also considered in this research.A flat surface without jetting outlet was utilized as contrast and the influence of jetting outlet's diameter and jetting angle on bionic jetting surface model's drag reduction effect was investigated by numerical simulation method; the structure parameters were investigated when the model had the best drag reduction effect.The influence of main flow field velocity on drag reduction effect and the relation between jetting velocity and drag reduction effect under different main flow field velocity conditions were studied based on the best structure parameters; bionic jetting surface's energy saving effect was also discussed in different flow velocities.Drag reduction mechanism of bionic jetting surface was studied and mechanism that jetting outlet's diameter, jetting angle and flow field velocity influence on drag reduction characteristic were researched by the analysis of the wall sheer stress, static pressure and other flow field parameters.