Arquimea recently developed a Heat Pipes and Radiators Assembly (HPRA) for the 3MI Instrument (Leonardo S.p.A., Campi Bisenzio site) onboard MetOp SG satellite (Airbus DS, ESA). Arquimea was in charge of the design, manufacturing, verification and testing of this HPRA, following the corresponding specifications from The Leonardo Company. Six models have been produced and delivered (STM, QM, FM1, FM2, FM3 and FS) along the six years this project took place. This HPRA comprises five radiators working at different temperature levels, ethane HPs, ammonia HPs, a supporting structure, a sunshield, insulation (MLI, SLI, washers), electrical parts (heaters, thermistors, thermostats) and titanium brackets and isostatics. Two of the radiators were small independent subassemblies that included a radiator, heat pipes, electrical parts and insulation. This HPRA turned out to be an important engineering, production and testing challenge, given the demanding performances required to this assembly, both thermal (temperature levels, gradients and insulation) and mechanical (stiffness, vibration levels, thermoelastic loads). To remark one of the radiators and the corresponding HP operate at very low temperatures (around -100ºC), while the rest operate at more usual minimum temperature levels (-40ºC/-5ºC). Besides, the HPRA is very compact. All the hardware is practically contained in an envelope 1mx0,5mx,0,65m (excluding part of the ammonia HP, the most protruding items). In particular, the gap between the coldest radiator and the supporting structure is less than 10 mm. This narrow gap turned out to be a very stringent design driver for the overall system, specially the insulation. The HPRA models underwent several demanding thermal and mechanical test campaigns (including vacuum testing, thermal cycling and bake-out) to demonstrate their capabilities. This paper shows the HPRA design, as well as the overall, manufacturing, verification and testing process made by Arquimea.
Pastor et al. (Sun,) studied this question.