Study on Temperature Field and Thermal Stress for an Insulated Composite Wall
In this dissertation, the mathematical models of thermal conduction procedure and thermal deformation for an insulated composite wall are established. That thermal conduction model takes complicately environmental changes (such as solar radiation, building self-radiation, reflecting ground radiation, air temperature, outdoor heat convection and indoor heat convection) into account. The thermal conduction problem is solved using finite difference method on spatial domain and DIPIM on time domain respectively. Computational formulae of thermal stress are deduced based on theory of thermal elasticity and plane section assumption. Finally, both the hourly temperature field and the thermal stress for an exteriorly and an interiorly insulated composite wall within a typical day of winter and summer are analyzed. Computational results show although the exterior insulation system is more beneficial to the stability of primary wall than interior one, the effect of environmental changes on mortar cracking and decorative materials inside the exteriorly insulated system than that inside the interiorly insulated system. The temperature gradient inside the insulated lamination is bigger than that in other laminations for any insulated system within whether winter or summer. In addition, the temperature gradient inside the insulated lamination for the interiorly insulated system within winter is bigger than that within summer, but the temperature gradient inside the insulated lamination for the interiorly insulated system within summer is bigger than that within winter. Although the exteriorly insulated system is more beneficial to the stability of primary wall than the interiorly insulated, the effect of environmental changes on mortar cracking and decorative materials for the exteriorly insulated system is bigger than that for the interiorly insulated. An exteriorly insulated system is more beneficial to the primary wall than an interiorly insulated system according to environmental attacks on the primary wall.