Melina Aero Teknoloji Geliştirme ve Dizayn Bürosu A.Ş. was founded in 2016 within ITU Arı Technopolis. Melina Aero is developing model based design and simulation software for the creation of digital twins of physical systems. One of these software, FlowNetMaster, is used to build digital twins of thermal-fluidic systems. Thermal-fluidic systems cover a broad range from water grids to natural gas pipelines, to heating ventilation cooling and refrigiration (HVAC&R) systems and to power and propulsion systems. It becomes possible to design, simulate and optimize physical systems using aforementioned software solutions. Through the model based design approach both design times and also capital and operational expenditures are all reduced. Furthermore, connectivity of the digital twin created within the software environment with its physical twin opens the possibility for a myriad of applications.