Research On Damage Effect Of Dynamic Explosion Load On Typical Cabin Structure

Anti-ship weapon is an important threat faced by large surface ships.Under its own high rapidly movement,it can penetrate the ship’s side or deck structure into the interior cabin,and maintain a certain speed of movement for dynamic explosion.The cabin structure will be damaged by various damage elements such as shock wave and high-speed fragments.Under the influence of the kinematic speed,the load characteristics of damage element and the damage to the cabin structure are different from that of static explosion.With the emergence of various ultra-high-speed anti-ship weapons,the effect of the movement velocity of anti-ship weapons on the load characteristics and damage effect of damage elements cannot be ignored.In order to master the load characteristics of the damage elements and the damage effect on ship cabin structure under dynamic explosion,and to support the development of ultra-high speed anti-ship weapon and the design of efficient protective structure,it is necessary to carry out research on the damage effect of dynamic explosive load on typical cabin structure.Based on the research background of the dynamic explosion of semi armor piercing anti-ship weapon warhead inside the ship cabin,aiming at the problems in the present research such as the research on dynamic explosion load characteristics in cabin is relatively few and lack of experimental data to support,the damage effect of dynamic explosion load action on cabin structure are not sufficiently studied,this paper by means of theoretical analysis,numerical simulation and experimental method,studies the characteristics of dynamic explosion load,the damage effect of alone and combined action of dynamic explosion load on the cabin structure.(1)The experimental study on the explosive load characteristics of the warhead in the cabin is carried out.The results show that when the warhead explodes dynamically,the overpressure peak of the initial shock wave at the measuring point with the positive movement speed of the warhead is higher than that under the static explosion,the radial flying velocity of the fragment is faster than that under the static explosion,and the scattering angle of the fragment shifts towards the warhead.The numerical simulation of warhead dynamic explosion in cabin is carried out by finite element software.Combined with the empirical formula results and experimental results,the effectiveness of the numerical simulation method is verified.(2)The influence of warhead movement velocity on the load characteristics of explosion shock wave and fragment in the cabin and the damage effect of individual explosion load on typical cabin structure are studied.The results show that: 1)the distribution of shock wave field in the cabin under dynamic charge explosion is asymmetrical.The increase of the movement velocity of the charge has an enhancement effect on the shock wave load of the measuring point facing the velocity direction,and a weakening effect on the shock wave load of the measuring point opposite the velocity direction.The damage characteristics of the typical single-compartment structure under dynamic explosion shock wave load are affected by the charge movement velocity and charge equivalent.With the increase of the charge movement velocity,the damage degree of the plate frame facing the charge movement direction increases,and the damage degree of the plate frame opposite the charge movement direction decreases.When the charge equivalent is large,the damage degree of the plate frame parallel to the charge movement direction is more sensitive to the change of the charge movement velocity.The overall damage range and degree of the typical multi-compartment structure are affected by the movement velocity of the charge.The damage degree of the adjacent cabin plate frame facing the movement direction of the charge increases with the increase of the movement speed of the charge,while the damage degree of the adjacent cabin plate frame opposite the movement direction of the charge decreases.The whole cabin structure presents a ‘+’shaped asymmetric damage in the horizontal and vertical directions.2)The movement velocity of the warhead has an enhancement effect on the velocity of the fragments scattering along the movement direction of the warhead,and a weakening effect on the velocity of the fragments scattering along the opposite movement direction of the warhead,and the whole scattering area of the fragment group shifts to the movement direction of the warhead.The fragments produced by the cylindrical warhead dynamic explosion in the center of typical singlecompartment structure cause different degrees of damage to all kinds of plate frames.With the increase of the movement velocity of the warhead,the damage degree of the plate frame facing the movement direction of the warhead increases,and the damage degree of the plate frame opposite the movement direction of the warhead decreases.The damage area on the plate frame parallel to the movement direction of the warhead shifts to the movement direction of the warhead.(3)The characteristics of the combined action of dynamic explosion shock wave and dynamic explosion fragment load are analyzed by theoretical method.The theoretical calculation model of the combined action critical distance between dynamic explosion shock wave and dynamic explosion fragment is established.It is found that the movement velocity of warhead has obvious influence on the combined action critical distance of dynamic explosion load in the forward and reverse directions of the warhead movement.The influence of the velocity movement of warhead on the combined action critical distance of dynamic explosion load is analyzed by numerical simulation,and the rationality of theoretical calculation model is verified.The damage effect of multi-compartment structure under the combined action of dynamic explosive loads is studied.The results show that the time sequence of the shock wave and fragment generated the warhead dynamic explosion on all kinds of plate frames is different.When the movement velocity of the warhead is 600 m/s,the explosion cabin plate frame is first subjected to the action of shock wave,and then it is hit by the fragment group.The damage process of the adjacent cabin plate frame can be divided into two stages: the combined action of dynamic explosion load and the impact of the plate frame of the explosion cabin.With the increase of the movement velocity of the warhead,the damage degree of the adjacent cabin plate frame facing the movement direction of the warhead increases,the damage degree of the adjacent cabin plate frame in the direction opposite the movement direction of the warhead is weakened.The whole cabin structure presents a ‘+’shaped asymmetric damage in the horizontal and vertical directions.