Shape identification of cavity in structures using thermal testing data
based on adjoint variable and finite element methods
Kotaro Maruoka, Takahiko Kurahashi, Tetsuro Iyama
Nagaoka University of Technology, Nagaoka, Japan 940-2188, [email protected]
In recent years, numerical simulations on shape identification are frequently carried out, and a lot of examinations are performed for various physical problems [1], [2]. In this study, we present the shape identification of cavity in structures using the thermal testing data based on the adjoint variable and the finite element methods. In case of thermal testing, the position of the defect is found by thermal image. However, the size and the shape of the defect can’t be measured by the thermal image. Therefore, we develop a method that the shape of the defect is identified using the temperature measurement data on structure surface based on the adjoint variable and finite element methods. In this study, a structure with cavity is made by 3D printer, and the numerical simulation of shape identification is carried out for the known cavity shape problem. The experimental apparatus and the example of finite element mesh are shown in Figures 1 and 2.
Figure 1, Experimental apparatus Figure 2, Example of finite element mesh
REFERENCES
[1] K. Shintani, H. Azegami, Bead shape optimization in frequency response problem, JSIAM Letters, 8 (2016) 13-16.
[2] T.Kurahashi and H.Oshita, Evaluation of 3D Reinforcement Corrosion Shape in Concrete Based on Observed Temperature on Concrete Surface, Int.J.Comput.Sci.，4，4 (2010) 340-351.
Test pieces
Hot plate
Thermocouple With cavity Without cavity
(15-mm thickness)
