Objective Non-pressure tank is an important component of double hull submarine. With the increasing diving depth, in order to reduce the structure weight and increase the payloads, the structural form of non-pressure tank of submarine need to be optimized.

Methods In this paper, the thickness, frame spacing and stiffener section dimensions of the non-pressure tank are selected as the design variables; the structural strength, stability and geometrical requirements are set as the constraints; and the total volume of the structure is determined as the objective function. Based on a simulated-annealing algorithm, a special code and optimization tool are combined to form an optimization plan for a transverse non-pressure tank using Matlab software,and qualitative analysis is conducted for the optimized design results.

Results Under the premise of meeting the requirements of recent codes and standards, the results indicate that the structural volume of the optimized plan is reduced by 27.2% compared to the original plan.

Conclusion The results of this study can provide useful references for the design of non-pressure tanks.