| As box-type mobile workstations, shelters are frequently used as special carriages of military vehicles. The delaminating problem under thermal loads, which does great harm to the function and appearance of shelters, is the most common quality problem during the lifecycle of shelters. In this thesis, one type of communication command shelter in one of PLA's factory has been studied, and FEM (finite element method) was introduced to research the delaminating problem under thermal loads.This thesis first analyzes the forms of heat transfer under thermal loads, and establishes a heat transfer model for the temperature field calculation. CAD software is applied to establish the geometric model according to the drawings that the factory provided. By comparison and research of several finite element models, a finite element model is established for the shelter body and other similar structures. And the temperature field of the shelter under real thermal environment is got with FEM software.The thermal-structural coupled method with FEM software is used to get the thermal deformation of the shelter and the thermal stress of the components of it. The analysis on the results shows that the damage caused by the thermal stress in the upper layer of the core material of the board is an important cause of delamination. Based on the thermal stress analysis of the whole shelter, the core material with void defects of various sizes in the upper layer is analyzed, which shows that the void defect is another important factor causing delamination. The consistency between the analysis and the experimental results of the factory proved the correctness of the analysis in this thesis. To solve the delaminating problem, the core material strength should be enhanced and the surface void size should be controlled.Finally, combined with the production process of the shelter body, some feasible measures are proposed to solve the delaminating problem on the basis of the FEM analysis results.
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