Numeric Thermal Bridges Simulation: Approaching Optimized Usability for Sloped and Rounded Shapes

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Computational numeric thermal bridge simulation can be considered a state-of-the-art technology for evaluating the thermal behavior of building component intersections. Conductive processes (and with some restrictions convective and radiative processes as well) inside of building details can be evaluated; Such analyses can help improve and optimize constructions. This can be necessary to ensure the durability of constructions and to avoid increased heat flow, low surface temperatures, and condensation problems. Numeric simulation tools regularly use finite differences methods, which approximate reality to a high degree. This requires the geometrical representation of such a thermal bridge to be discretized as a uniform grid. This – as a consequence – requires models that are reduced to strictly orthogonal structures, which has a large impact on the modelling of building joints with sloped or rounded surfaces and elements. Such elements need to be simplified to orthogonal elements, resulting in step-by-step representations of slopes and curvatures. While the accuracy of thermal bridge simulations is considered sufficient, the modelling efforts of such details and their simplification often represent a time-consuming and error-prone activity.In this context, the contribution presents recent efforts in the development of the state-of-the-art tool AnTherm (www.antherm.eu) that allow the automated generation of slope and curvature representations within the modelling canvas of the tool. As a consequence, the modelling and simplification of sloped and rounded elements can be done fast and with a high degree of accuracy. This contribution describes the general method, its implementation, an analysis of the overall usability of the approach, modelling examples and an outlook to future developments.

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Periodical:

Edited by:

Lucia Mankova

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527-535

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T. Kornicki et al., "Numeric Thermal Bridges Simulation: Approaching Optimized Usability for Sloped and Rounded Shapes", Applied Mechanics and Materials, Vol. 824, pp. 527-535, 2016

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January 2016

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