Digital twins are popular for Industry4.0 applications, especially for smart factories. From this driving area of interest, standardization attempts emerged, such as the RAMI4.0 with Asset Administration Shell (AAS), or languages for the automation of manufacturing planning (AutomationML) and operation (OPC-UA). However, these do not yet sufficiently formalize and include computer-aided engineering (CAE) simulation for physical behaviour. This and similar gaps are still unbridged between the many structures of data that collide in digital twins. Therefore, one goal of the Digital Twin for Multiphysics Lab (DT4MP) is to explore a possible harmonization between the semantics and the formats of these heterogeneous data sources. With this orientation, the VMAP Standard is central for the CAE domain. A second goal of the lab is the exploitation of the gained interoperability through hybrid rule/data models, surrogates, and uncertainty quantification. Finally, the lab aims to make the insights and developed methods available for small and medium sized enterprises with the goal to use these technologies for their sustainability and resource efficiency. In this contribution, we present the Lab, a cooperation of Fraunhofer SCAI, University of Applied Sciences Bonn-Rhein-Sieg and Dr. Reinold Hagen Stiftung by highlighting the demand for interoperability with and of the simulation domain, and by explaining the core concepts of the MpCCI digital twin ontologies and their use in CAE. The main target is to show the deep connection of the physical behaviour of simulated systems with conditions of production (e.g. machine parameters), the history of the material, and their measurement conditions. In this, we give an overview of an intermediate information model that spans from production, across materials and measurement to the details of CAE simulation models and processes. We then demonstrate examples of the researched methods at the DT4MP Lab for data permeability and interpretability and summarize a developed methodology to implement and use VMAP semantically in a digital twin.