| As a sailing submarine experiences dangerous situations in underwater,conducting the emergency rising is the most effective means to ensure its survival.In this paper,the problem of excessive roll in submarine emergency buoyancy process is studied,the law of emergency rising motion is mainly analyzed,and a reasonable control strategy of emergency buoyancy is preliminarily discussed.In this paper,an experimental study on submarine emergency rising is carried out by the means of combining model test with numerical calculation.Referring to the relevant design data of a famous model submarine abroad,a submarine model for test is specially designed in this paper.Based on the similarity theory,the superstructure and water holes of submarine model are designed in detail,and the implementation process of submarine emergency rising test is optimized.The submarine model emergency rising test is carried out in towing pool.13 test conditions are designed according to 4 kinds attributes:position of blown buoyancy load,initial metacentric height,sternplane angle and initial speed,and 26 sets of valid experimental data are obtained eventually.Aiming at the emergency rising motion of submarine,this paper proposes an effective numerical method based on CFD software STARCCM+,and makes a detailed comparison and verification to determine the mesh type and turbulence physical model.The polyhedral mesh is used in the overlapping area of the computational domain;while the trim volume mesh is used in the background area,which can not only control the number of meshes but also ensure the computational accuracy.In addition,the turbulence model uses SST k-ω model.Through comparing the results of model test and numerical calculation,the feasibility of the numerical method for the submarine emergency rising is verified.Based on the analysis of model test results and numerical calculation results,the influences of initial speed,metacentric height,position of blown buoyancy load and sternplane angle on emergency rising motion are summarized.It is found that there is a positive correlation relation between the drift angle and the maximum roll angle of submarine emergency rising.It is pointed out that the fundamental cause of rolling instability during emergency rising with an initial speed is the excessive development of the drift angle and the yaw instability. |
