Mechanically Pumped Advanced Control Loop: a Solution for High Power Platforms

Two-phase mechanically pumped loops have been identified as the potential solution for the heat management of high-powered platforms, such as next generation telecommunications satellites. The proposed concept Mechanically Pumped Advanced Control Loop (M-ACL) combines the advantages of a two-phase modular thermal control system and a mechanically pumped loop. In single-phase fluid loops temperature rise in the fluid and flow rate are directly proportional to the required heat transfer rate. High cooling loads lead to a large temperature rise and high pump power. For more effective thermal transport, the single-phase loop can be replaced by a two-phase one. This allows employing the latent heat of vaporization to significantly reduce flow rates, decrease temperature gradients, and increase heat transfer coefficients. M-ACL concept has been defined after an extensive literature and patents review. It is based on the multi-evaporator, multi-condenser Advanced Control Loop (ACL) concept, which means an integrate solution for the complete thermal control of the platform. The implementation of a mechanical pump in the system means an important increase of the heat transport capability that depends on the pump pressure rise characteristic. A trade-off has been performed to define main mechanical pump and M-ACL features. Additionally, a M-ACL engineering model has been designed based on a NACPA pump from RealTechnologie AG. In this study, the detailed design is presented as well as simulation results using a thermo-hydraulic model developed in EcosimPro simulation tool.