Coupled simulation of thermally active building systems to support a digital twin

Based on 2050 Swiss and European Union targets, significant energy performance improvements will be required for new and renovated buildings. However, the construction industry has a poor record for delivering productivity and efficiency advancement. As proven in other industries, digital methods can shorten product development time and cost by reducing prototyping with the use of numerical simulation. Further, a digital twin is an extensive computational model of a product that is planned to improve over its lifecycle by leveraging operational data. This paper presents a coupled simulation for the thermal design of a heating and cooling system that is integrated with a lightweight roof structure. The concrete roof structure is shape optimised to provide a low embodied energy building element, which is thermally activated to supply space conditioning from a renewable geothermal source. This work is focused on the modelling methodology used by the energy domain to support the development of a digital twin for a multifunctional building element. High-resolution analysis is used to resolve building physics issues and to provide the initial system performance. A parametric geometry model is used to apply the hydronic pipework to a complex roof shape. With input from the previous two steps, a reduced resolution method is used to add the characteristics of the system to an industry standard whole building simulation model. This final step allows for the development of initial control strategies for the novel multifunctional element. The implications of the research findings are discussed in the context of possible alternations to the building design process due to the influence of digital fabrication. (c) 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/)