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A presente dissertação tem como objetivo identificar modelos numéricos para a inspeção
não destrutiva de componentes, obtidos por Manufatura Aditiva, através da Termografia
Ativa (TA).
Um dos grandes desafios da aplicação dos Ensaios não destrutivos (END) é a capa-
cidade de prever a profundidade e o tamanho do defeito. Tendo em conta que dois dos
materiais estudados são compósitos poliméricos obtidos por manufatura aditiva, estes
componentes têm baixa condutividade térmica o que apresenta um desafio na aplicação
dos END.
Recorrendo ao Ansys APDL foram desenvolvidos modelos em elementos finitos que
simulam os fenómenos físicos da transmissão de calor. Estes modelos foram validados
através de referências obtidas na literatura, nomeadamente resultados de simulações
numéricas da termografia realizadas a modelos de provetes com delaminações inseridas
a diferentes profundidades. Também se recorreu a expressões analíticas provenientes da
literatura, para a determinação do tempo necessário para se obter o contraste máximo.
O uso das expressões analíticas mostraram ser eficazes na previsão do momento de
contraste máximo, o que apesar de terem um desvio relativo, é possível estimar o tamanho
do defeito assim como a sua posição.
A b s t r ac t The present dissertation aims to identify numerical models for the non-destructive inspec- tion of components, obtained by Additive Manufacturing, through Active Thermography (AT). One of the great challenges in the application of Non destructive Testing (NDT) is the ability to predict the depth and size of the defect. Considering that two of the materials studied are polymeric composites obtained by additive manufacturing, these components have low thermal conductivity, which presents a challenge in the application of NDT. Using Ansys APDL, finite element models were developed that simulate the highly complex physical phenomena resulting from thermography. These models were validated through references obtained in the literature, namely results of numerical simulations of thermography tests carried out on specimens with delaminations inserted at different depths. Analytical expressions from the literature were also used to determine the time needed to obtain maximum contrast. The uses of analytical expressions proved to be effective in predicting the instant of maximum contrast, which despite having a relative deviation, it is possible to estimate the size of the defect as well as its position.
A b s t r ac t The present dissertation aims to identify numerical models for the non-destructive inspec- tion of components, obtained by Additive Manufacturing, through Active Thermography (AT). One of the great challenges in the application of Non destructive Testing (NDT) is the ability to predict the depth and size of the defect. Considering that two of the materials studied are polymeric composites obtained by additive manufacturing, these components have low thermal conductivity, which presents a challenge in the application of NDT. Using Ansys APDL, finite element models were developed that simulate the highly complex physical phenomena resulting from thermography. These models were validated through references obtained in the literature, namely results of numerical simulations of thermography tests carried out on specimens with delaminations inserted at different depths. Analytical expressions from the literature were also used to determine the time needed to obtain maximum contrast. The uses of analytical expressions proved to be effective in predicting the instant of maximum contrast, which despite having a relative deviation, it is possible to estimate the size of the defect as well as its position.
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ANSYS Manufatura Aditiva Ensaios não Destrutivos (END) Termografia ativa (TA) Simulação
