Research On Anti-shock Damage Characteristics Of Double-Deck Bulkhead Structure

Warship was bound to be missile attacks because it was the main carrier of modern naval warfare,attacker,and the main target of the enemy attack.With the rapid development of modern anti-ship missile,its hidden,hit accuracy and warhead charge volume were greatly improved.The warhead exploded inside the cabin produced explosion shock wave and a large number of high-speed fragmentations which caused damage to the hull,resulting in the ship lost its combat capability or even sank.Bulkhead structure was the main protective structure of the ship cabin due to its hull internal prominence.Therefore,it was of great military value and practical significance to conduct research on the impact resistance and damage performance of ship bulkheads under shock wave and penetrating load,and to obtain better bulkhead structure with better impact resistance and damage performance.Based on shock wave and penetration theory,the numerical simulation method of the combined action of shock wave and high-speed fragments was studied in this paper;the dynamic response of the structure under combined action of shock wave and penetration load and shock wave and penetration was studied,then obtained the failure modes and damage characteristics of the bulkhead structure under different loads;on the basis of previous studies,researched on the structural dynamic response of the double-deck bulkhead structure with typical I-type sandwich panels under shock wave and penetration load,obtained the damage mode and damage characteristics of double-deck bulkhead structure with type I sandwich panel;based on the evaluation index of impact resistance and damage performance of bulkhead structure,obtained the double-deck bulkhead structure of sandwich panels with the best impact-resistance by comparing the shock-damage properties of double-layer bulkheads of type I,X and V sandwich plates under the combined action of shock wave and penetration;used orthogonal test optimization method to achieve the optimization of bulkhead structural parameters including panel thickness,backplane thickness,sandwich panel thickness and sandwich panel angle in order to obtain the optimal structural parameters of the double-deck bulkhead with the best impact resistance and impact resistance.The main work of this paper is as follows:(1)Research on shock wave and penetration theory and simulation method validation.The theory of shock wave in air explosion and the theory of penetration mechanics were studied,simulated the combined effect of shock wave and high-speed fragments loading by the numerical simulation method,compared the numerical simulation results with theoretical formula,thereby,verified the reliability of the numerical simulation method,provided the basis for the study of the dynamic response of the bulkhead structure under the combined action of shock wave and fragments;(2)Study on ship bulkhead structure response under shock wave,penetration load and the combined effect of shock wave and penetration.Considering the characteristics of shock wave and penetration load and the calculation precision and efficiency,determined the optimal grid size of the calculation model of the typical single-layer bulkhead structure,studied the dynamic response process of the typical single ship bulkhead structure under shock wave,penetration and the combination of shock wave and penetration,obtained the damage modes and anti-damage characteristics of the ship’s bulkheads under different loads,found the enhancement effect of the damage that shock wave and penetration combined effect on bulkhead structure.(3)Study on the dynamic response of sandwich double deck bulkhead structure under combined action of shock wave and penetration.The response process of double-deck bulkhead structure of typical I-type sandwich panel under the combination of shock wave and penetration was studied,obtained the failure mode and damage characteristics of the double-deck bulkhead structure of the sandwich panel,under the prerequisite of keeping the structural quality of the bulkhead unchanged,compared the impact damage properties of double-deck bulkheads of type I,X and V sandwich panels under the combined action of shock wave and fragments by evaluating index of shock damage performance of bulkhead structure,obtained the double-deck bulkhead structure with the best impact resistance and damage performance.(4)Optimization of the double-deck bulkhead size parameters of sandwich panels under the combined action of shock wave and penetration.For the sandwich panel double-deck bulkhead structure with the best impact resistance in(3),optimization of the structure of the parameters,including panel thickness,backplane thickness,sandwich panel thickness,and sandwich panel angle by using Orthogonal test optimization method,and obtained the structural parameters of the double-deck bulkhead with the best impact resistance.