Development of an Innovative Diaphragm Pump and Two-Phase Mechanically Pumped Loop for Active Antennas

The development of Active Phased Array Antennas (APAAs) is a key enabler to effectively accommodate the growing demand of data transfer in commercial telecommunication satellites. A highly efficient and integrated thermal management system is required so as to reject the waste heat produced by the antenna�s Solid State Power Amplifiers (SSPAs). The development of such a thermal control system presents a number of technical challenges, chief among them being the large number of heat sources involved (typically ranging from 100 to 1000, with varying duty cycles), the need for spatial and temporal isothermal conditions across the set of SSPAs, as well as a low thermal gradient between the SSPAs and the working fluid, high total heat dissipation (10+ kW), high heat flux (20+ W/cm^2 at the evaporator�s interface) and large distances between the radiator and the payload, among others. An international consortium led by AVS is currently developing an ammonia two-phase pumped loop for APAAs within the frame of the IMPACTA project. MPLs (two-phase pumped loops in particular) are remarkably well suited for applications involving large heat loads, transfer of thermal energy over large distances (e.g. distributed payloads), high heat fluxes and payloads with tight temperature stability requirements.

In addition, a novel positive displacement pump for spacecraft thermal control is being developed by AVS. The pump features a diaphragm architecture, piezoelectric actuator and passive check valves. A series of performance characterization tests of the EM have been conducted using a two-phase mechanically pumped loop test system in laboratory conditions.

It is the purpose of the present paper to provide an overview of the IMPACTA project, current status and goals, as well as a description of the PDPump project, outlining the design and main requirements, as well as the development history and current status.